bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acoustic Resonance in an Axial Multistage Compressor Leading to Non-Synchronous Blade Vibration
Authors: Fiquet Anne-Lise , Aubert Stéphane , Brandstetter Christoph , Buffaz Nicolas , Vercoutter Agathe 
Published: March 2021

Abstract
Significant non-synchronous blade vibrations (NSVs) have been observed in an experimental three-stage high-speed compressor at part-speed conditions. High-amplitude acoustic modes, propagating around the circumference and originating in the highly loaded stage-3, have been observed in coherence with the structural vibration mode. In order to understand the occurring phenomena, a detailed numerical study has been carried out to reproduce the mechanism. Unsteady full-annulus Reynolds-averaged Navier–Stokes simulations of the whole setup have been performed using the solver elsA. The results revealed the development of propagating acoustic modes which are partially trapped in the annulus and are in resonance with an aerodynamic disturbance in rotor-3. The aerodynamic disturbance is identified as an unsteady separation of the blade boundary layer in rotor-3. The results indicate that the frequency and phase of the separation adapt to match those of the acoustic wave and are therefore governed by acoustic propagation conditions. Furthermore, the simulations clearly show the modulation of the propagating wave with the rotor blades, leading to a change of circumferential wave numbers while passing the blade row. To analyze if the effect is self-induced by the blade vibration, a non-coherent structural mode has been imposed in the simulations. Even at high vibration amplitude, the formerly observed acoustic mode did not change its circumferential wave number. This phenomenon is highly relevant to modern compressor designs, since the appearance of the axially propagating acoustic waves can excite blade vibrations if they coincide with a structural eigenmode, as observed in the presented experiments.
Experimental and Numerical Study of Laminar-Turbulent Transition on a Low-Pressure Turbine Outlet Guide Vane
Authors: Jonsson Isak , Deshpande Srikanth , Chernoray Valery , Thulin Oskar , Larsson Jonas 
Published: March 2021

AbstractThis work presents an experimental and numerical investigation of the laminar-turbulent transition and secondary flow structures in a turbine rear structure (TRS). The study was executed at engine representative Reynolds number and inlet conditions at three different turbine load cases. Experiments were performed in an annular rotating rig with a shrouded low-pressure turbine upstream of the TRS test section. The numerical results were obtained using the shear stress transport k − ω turbulence model and the Langtry–Menter γ − θ transition model. The boundary layer transition location at the entire vane suction side is investigated. The location of the onset and the transition length are measured using IR-thermography along the entire vane span. The IR-thermography approach was validated using hot-wire boundary layer measurements. Both experiments and computational fluid dynamics (CFD) show large variations of transition location along the vane span with strong influences from endwalls and turbine outlet conditions. Both agree well with traditional transition onset correlations near midspan and show that the transition onset Reynolds number is independent of the acceleration parameter. However, CFD tends to predict an early transition onset in the midspan vane region and a late transition is present in the hub region. Furthermore, in the hub region, CFD is shown to overpredict the transverse flow and related losses.
Binder Jetting of Silicon Steel, Part I: Process Map of Green Density
Authors: Rishmawi Issa , Vlasea Mihaela 
Published: March 2021

Abstract
This study focuses on developing and demonstrating a straightforward workflow for identifying pathways to increase green part density in binder jetting additive manufacturing (BJAM) using statistically driven process maps. The workflow was applied to investigate the effects of process parameters toward improving green part density, with a direct application in manufacturing of Fe-Si components. Specifically, a half-factorial experimental design was used to study the effects of four key parameters—layer thickness, powder spreading speed, roller rotational speed, and binder saturation—on Fe-Si spherical powder with D50 of 32.40 µm. Relative bulk density was estimated via three methods: geometrical and mass measurements, the Archimedes test, and CT imaging. The study discusses relative bulk density as well as localized density variation in the printed parts, which is attributed to both parameter selection and inherent process variability. A regression analysis was used to reveal the significance of main effects and second-order interactions. The regression model (R2 = 0.915) was used to derive an expression for green density as a function of the parameters and had a prediction error of 0.96%. Based on the regression model, an optimized set of parameters was obtained that would maximize green density up to 57.96% for the machine and material system.
Assessment of Turbulence Models for Low Reynolds Number Flows and Their Computational Costs, Part 2: Square Prism in Cross Flow
Authors: Mancuso Thomas , Mukherjee Abhijit 
Published: March 2021

AbstractThe accuracy of six turbulent flow modeling techniques in an unsteady solution is evaluated against experimental data for a square prism in cross flow. The selected models, shear stress transport (SST), SST-SAS, Reynolds stress model (RSM), partially averaged Navier–Stokes (PANS)-SST, detached eddy simulation (DES), and large eddy simulations (LES), models are the same as those presented in Part 1 of this study, which focused on flow in a staggered tube bank. For this geometry, the SST model proved to be effective at capturing the averaged Nusselt values per side of the square with relatively low computational costs. The SST model, however, showed poorer fidelity to the local Nusselt number profile compared to the experimental data. The LES approach provided a more accurate representation of the local Nusselt number but the computational cost was significantly higher. The PANS modification to the SST model did provide a noticeable improvement in accuracy at a reasonable cost while the SAS modification did not see the same improvement. These conclusions are generally consistent with those found for the staggered tube bank in Part 1 of this study. This study can be used as a guide for the industrial user to select a turbulence model for a similar problem with a low Reynolds number and significant flow separation.
Premature thelarche in an infant girl with failure to thrive related to dietary soy exposure
Authors: Chang Serena Su Ying , Nagarajan Nandhakumar , Tan Joanne Mui Ching 
Published: March 2021

A 7-month-old female infant presented with failure to thrive. She was breastfed till 3 months of age, thereafter switched to soy-based milk formula. There was no history to suggest excess energy losses, recurrent infections or chronic diarrhoea. Three months after switching to exclusive soy-based milk formula, parents noticed significant enlargement of both breasts. Clinical examination was unremarkable except for enlargement of both breasts. None of the other secondary sexual characteristics were present. Initial blood investigations showed hyponatraemic hypokalaemic hypochloraemic metabolic alkalosis, which corrected after 2 days with intravenous hydration. The patient subsequently maintained normal electrolyte balance with recommended intake of cow’s milk-based standard formula milk.Further exploration of her soy-based milk revealed that it was low in sodium and calories, unsuitable for children. This was not a standard and approved infant soy-based formula milk. She achieved excellent weight gain and reduction of breast size on cessation of soy-based milk formula.
Age dependent associations of risk factors with heart failure: pooled population based cohort study
Authors: Tromp Jasper , Paniagua Samantha M A , Lau Emily S , Allen Norrina B , Blaha Michael J , Gansevoort Ron T , Hillege Hans L , Lee Douglas E , Levy Daniel , Vasan Ramachandran S , van der Harst Pim , van Gilst Wiek H , Larson Martin G , Shah Sanjiv J , de Boer Rudolf A , Lam Carolyn S P , Ho Jennifer E 
Published: March 2021

Abstract

Objective
To assess age differences in risk factors for incident heart failure in the general population.

Design
Pooled population based cohort study.

Setting
Framingham Heart Study, Prevention of Renal and Vascular End-stage Disease Study, and Multi-Ethnic Study of Atherosclerosis.

Participants
24 675 participants without a history of heart failure stratified by age into young (<55 years; n=11 599), middle aged (55-64 years; n=5587), old (65-74 years; n=5190), and elderly (≥75 years; n=2299) individuals.

Main outcome measure
Incident heart failure.

Results

Over a median follow-up of 12.7 years, 138/11 599 (1%), 293/5587 (5%), 538/5190 (10%), and 412/2299 (18%) of young, middle aged, old, and elderly participants, respectively, developed heart failure. In young participants, 32% (n=44) of heart failure cases were classified as heart failure with preserved ejection fraction compared with 43% (n=179) in elderly participants. Risk factors including hypertension, diabetes, current smoking history, and previous myocardial infarction conferred greater relative risk in younger compared with older participants (P for interaction <0.05 for all). For example, hypertension was associated with a threefold increase in risk of future heart failure in young participants (hazard ratio 3.02, 95% confidence interval 2.10 to 4.34; P<0.001) compared with a 1.4-fold risk in elderly participants (1.43, 1.13 to 1.81; P=0.003). The absolute risk for developing heart failure was lower in younger than in older participants with and without risk factors. Importantly, known risk factors explained a greater proportion of overall population attributable risk for heart failure in young participants (75%
v
53% in elderly participants), with better model performance (C index 0.79
v
0.64). Similarly, the population attributable risks of obesity (21%
v
13%), hypertension (35%
v
23%), diabetes (14%
v
7%), and current smoking (32%
v
1%) were higher in young compared with elderly participants.

Conclusions
Despite a lower incidence and absolute risk of heart failure among younger compared with older people, the stronger association and greater attributable risk of modifiable risk factors among young participants highlight the importance of preventive efforts across the adult life course.
Developing more detailed taxonomies of tobacco industry political activity in low-income and middle-income countries: qualitative evidence from eight countries
Authors: Matthes Britta Katharina , Lauber Kathrin , Zatoński Mateusz , Robertson Lindsay , Gilmore Anna B 
Published: March 2021

IntroductionHistorical evidence, predominantly from high-income countries (HICs), shows that the tobacco industry uses a recurring set of arguments and techniques when opposing tobacco control policies. This data formed the basis of a model of tobacco industry political activity known as the policy dystopia model (PDM). The PDM has been widely used in tobacco control research and advocacy and has subsequently been shown relevant to other unhealthy commodities industries in both HICs and low-income and middle-income countries (LMICs). Before it can be validated as a generic tool for researching corporate influence on policy, one needs to determine whether the PDM successfully captures contemporary corporate political activities in LMICs.MethodWe conducted semistructured interviews with 22 LMIC-based advocates and used the transcripts as the primary data source. The discursive and instrumental taxonomies constituting the PDM served as the starting point for the coding framework. Using thematic analysis, we combined deductive and inductive coding to ensure we captured all strategies from the PDM and the interviews.ResultsThis study found that the tobacco industry uses a set of discursive and instrumental strategies that is largely consistent across LMICs and with the PDM. We identified several minor contextual nuances absent from the PDM. Some of these nuances were characteristic to individual countries, while others to LMICs more broadly. They included the argument that tobacco control policies unfairly punish reputable tobacco industry actors, and an emphasis on instrumental strategies centred around maintaining a good image, rather than rehabilitating a tarnished image as emphasised in the PDM.ConclusionsAllowing for the nuances identified in this study, the PDM has been found to be fit for purpose. The revised model should now be tested through in-depth LMIC case studies and could be used to facilitate comparative studies of unhealthy commodity industries’ political activities.
Which came first, obstructive sleep apnoea or hypertension? A retrospective study of electronic records over 10 years, with separation by sex
Authors: An Eunjoo , Irwin Michael R , Doering Lynn V , Brecht Mary-Lynn , Watson Karol E , Aysola Ravi S , Aguila Andrea P , Harper Ronald M , Macey Paul M 
Published: March 2021

ObjectivesObstructive sleep apnoea (OSA) is a risk factor for hypertension (HTN), but the clinical progression of OSA to HTN is unclear. There are also sex differences in prevalence, screening and symptoms of OSA. Our objective was to estimate the time from OSA to HTN diagnoses in females and males.DesignRetrospective analysis of electronic health records (EHR) over 10 years (2006–2015 inclusive).SettingUniversity of California Los Angeles (UCLA) Health System in Los Angeles, California, USA.Participants4848 patients: females n=2086, mean (SD) age=52.8 (13.2) years; males n=2762, age=53.8 (13.5) years. These patients were selected from 1.6 million with diagnoses in the EHR who met these criteria: diagnoses of OSA and HTN; in long-term care defined by ambulatory visits at least 1 year prior and 1 year subsequent to the first OSA diagnosis; no diagnosis of OSA or HTN at intake; and a sleep study performed at UCLA.Primary and secondary outcome measuresThe primary outcome measure in each patient was time from the first diagnosis of OSA to the first diagnosis of HTN (OSA to HTN days). Since HTN and OSA are progressive disorders, a secondary measure was the relationship between OSA to HTN time and age (OSA to HTN=β1×Age+β0).ResultsThe median (lower and upper quartiles) days from OSA to HTN were: all −532 (−1439, –3); females −610 (−1579, –42); and males −451 (−1358, 0). Older age in both sexes was associated with less time to a subsequent HTN diagnosis or more time from a prior HTN diagnosis (β1 days/year: all −16.9, females −18.3, males −15.9).ConclusionsHTN was on average diagnosed years prior to OSA, with a longer separation in females. Our findings are consistent with underscreening of OSA, more so in females than males. Undiagnosed OSA may delay treatment for the sleep disorder and perhaps affect the development and progression of HTN.
Trends in known and undiagnosed diabetes, HbA1c levels, cardiometabolic risk factors and diabetes treatment target achievement in repeated cross-sectional surveys: the population-based Tromsø Study 1994–2016
Authors: Langholz Petja Lyn , Wilsgaard Tom , Njølstad Inger , Jorde Rolf , Hopstock Laila Arnesdatter 
Published: March 2021

ObjectivesThe aim of this study was to investigate time trends in known and undiagnosed diabetes, glycated haemoglobin (HbA1c) levels and other cardiometabolic risk factors in the general population as well as treatment target achievement among those with diabetes.Design and settingRepeated cross-sectional surveys in the population-based Tromsø Study.MethodsWe used age-adjusted generalised estimating equation models to study trends in self-reported and undiagnosed (HbA1c ≥6.5%) diabetes, cardiometabolic risk factors and the metabolic syndrome in 27 281 women and men aged 40–84 years examined in up to four surveys of the Tromsø Study between 1994 and 2016. Further, we analysed trends in diabetes treatment target achievement.ResultsDuring 1994–2016, diabetes prevalence increased in women (2.3% to 4.6%) and men (2.4% to 5.8%) and in all age groups, while the proportion of undiagnosed diabetes in women (32% to 17%) and men (37% to 24%) decreased. Blood pressure and total cholesterol decreased, while waist circumference increased in participants with and without diabetes, leading to a relatively stable prevalence of the metabolic syndrome throughout the study period. There was a marginal increase in HbA1c levels among participants without diabetes. Only half of those with diabetes achieved the treatment target of HbA1c ≤7.0%.ConclusionIn the last two decades, diabetes prevalence increased, while the proportion of undiagnosed diabetes declined. The prevalence of the metabolic syndrome remained stable throughout, driven by opposing trends with an increase in obesity and a decrease in other cardiometabolic risk factors. HbA1c treatment target achievement did not improve.
Training general practitioners in melanoma diagnosis: a scoping review of the literature
Authors: Harkemanne Evelyne , Baeck Marie , Tromme Isabelle 
Published: March 2021

BackgroundGeneral practitioners (GPs) play a key role in early melanoma detection. To help GPs deal with suspicious skin lesions, melanoma diagnostic training programmes have been developed. However, it is unclear whether these programmes guarantee the acquisition of skills that will be applied by GPs in their daily clinical practice and maintained over time.ObjectivesThis scoping review aimed to examine and compare educational programmes designed to train GPs in melanoma diagnosis using clinical (naked eye) examination alone or dermoscopy±clinical examination, and sought to inform on the long-term sustainability of the GPs’ acquired skills.Eligibility criteriaStudies eligible for inclusion evaluated educational programmes for teaching diagnosis of melanoma to GPs. MEDLINE, EMBASE and Cochrane databases were searched for relevant articles from 1995 to May 2020.ResultsForty-five relevant articles were found assessing 31 educational programmes. Most programmes that improved the diagnostic accuracy and long-term performances of the GPs, that is, increase in confidence, decrease in dermatologist referral for benign skin lesions and improvement in the benign/malignant ratio of excised skin lesions, trained the GPs in clinical diagnosis, followed by dermoscopy. To maintain long-term performances, these programmes provided refresher training material.ConclusionThis review shows that studies generally report positive outcomes from the training of GPs in melanoma diagnosis. However, refresher training material seemed necessary to maintain the acquired skills. The optimal form and ideal frequency for these updates have yet to be defined.
Model-based estimation of the economic burden of cholera in Africa
Authors: Mogasale Vittal , Ngogoyo Samuel Mwaura , Mogasale Vijayalaxmi V 
Published: March 2021

ObjectivesTo estimate the economic burden of cholera in Africa.SettingsCholera affected 44 countries in Africa.ParticipantsThe analysis used data from public sources in Africa published until September 2019.MethodsBased on existing data from field-based cost-of-illness studies, estimated cholera incidence rates, and reported cholera cases to WHO, this research estimates the economic burden of cholera in Africa from a societal perspective with 2015 as the base year. The estimate included out-of-pocket costs, public health system costs, productivity loss related to illness and an optional productivity loss related to premature deaths valued by the human capital approach. As various input data such as cholera incidence, hospitalisation rates and the number of workdays lost were not well defined, a series of scenario analyses and uncertainty analyses, accounting for unknowns and data variability, was conducted. Similarly, the value of time lost due to illness and deaths using the human capital approach was explored through scenario analyses.ResultsIn 2015, an estimated 1 008 642 cases in 44 African countries resulted in an economic burden of US$130 million from cholera-related illness and its treatment. When the estimated 38 104 cholera deaths were included in the analysis, the economic burden increased to US$1 billion or international $2.4 billion for the same year. At the same time, when only the 71 126 cases and 937 deaths reported to the WHO are considered, the economic burden was only US$68 million for the year 2015. The estimates of economic burden are thus heavily dependent on the cholera incidence rate, how time lost due to illness and deaths are calculated, hospitalisation rates and hospitalisation costs.ConclusionThe findings can be used as an economic justification for cholera control in Africa and for generating value-for-money evidence to underpin Ending Cholera—A Global Roadmap to 2030 with considerations to study limitations.
Change in prevalence of psychological and economic abuse, and controlling behaviours against women by an intimate partner in two cross-sectional studies in New Zealand, 2003 and 2019
Authors: Fanslow Janet , Malihi Zarintaj , Hashemi Ladan , Gulliver Pauline , McIntosh Tracey 
Published: March 2021

ObjectivesChanges in reported lifetime prevalence of psychological abuse, controlling behaviours and economic abuse between 2003 and 2019, and past 12-month prevalence of psychological abuse by an intimate partner were examined.DesignCross-sectional analysis.Setting and participantsData came from two surveys of family violence in New Zealand, conducted in 2003 and 2019. Respondents were ever partnered women aged 18–64 years old (2003 n=2673; 2019 n=935).Main outcome measuresPrevalence rates for psychological abuse, controlling behaviours and economic abuse were compared between the two study years using logistic regression. Sociodemographic and economic correlates of each abuse subtype were investigated. Interactions were examined between sociodemographic factors and the study year for reported prevalence rates.ResultsThere was a reduction in reported past 12-month experience of two or more acts of psychological intimate partner violence (IPV) from 8.4% (95% CI 7.3 to 9.6) in 2003 to 4.7% (95% CI 3.2 to 6.2) in 2019. The reported lifetime prevalence of two or more acts of controlling behaviours increased from 8.2% in 2003 (95% CI 7.0 to 9.5) to 13.4% in 2019 (95% CI 11.0 to 15.7). Lifetime prevalence of economic IPV also increased from 4.5% in 2003 (95% CI 3.5 to 5.5) to 8.9% in 2019 (95% CI 6.7 to 11.1). Those who were divorced/separated or cohabiting, and those living in the most deprived areas were more likely to report past year psychological IPV, lifetime controlling behaviours and economic abuse. A higher proportion of women who were married or cohabiting reported controlling behaviours in 2019 compared with 2003.ConclusionWhile the reduction in reported past year psychological IPV is encouraging, the increase in the lifetime prevalence of controlling behaviours and economic abuse from 2003 to 2019 is worth critical evaluation. Results highlight potential gaps in current IPV prevention programmes, the need to identify and address underlying drivers of abusive behaviour and the importance of measuring multiple forms of IPV independently.