bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D CFD Approach to Predict the Performance of a Centrifugal Compressor With Surge and Choke Limits
Authors: Sriram Abishek , Schlautman Jeff , Varshney Mehul , Maiti Dipak , Pasunurthi Shyam Sundar , Ding Hui , Ranganathan Raj 
Published: December 2021

Abstract
Centrifugal compressor has widespread applications in areas such as aerospace, automotive, power and process industries and hence the prediction of its performance is crucial at the design stage. Traditional design, build and test are accelerated through numerical simulation as a virtual test bed for compressor development. In this work, a CFD methodology has been developed to predict the performance of a centrifugal compressor with its surge and choke limits. The transient, compressible flow in a moving domain with body-fitted unstructured mesh is solved in Simerics-MP. The distributed parallel solver of Simerics-MP enables to perform the complete performance map of a centrifugal compressor in a day.
The phenomena of surge and choke in a centrifugal compressor is of paramount importance as it determines the limiting points of operation for a particular speed of the compressor. Surge occurs at low flow rates, and it is characterized by instabilities causing undesirable noises that lead to drop in the operational efficiency. It can also result in wear and tear of the impeller blades. Whereas choke occurs at high flow rates with no further increase in pressure and it is accompanied by aberrant vibrations. The CFD simulation predicts the instabilities occurring at surge such as pressure oscillations and flow reversal accurately, which is used as a criterion for the prediction of surge point. The choke phenomenon is characterized by fluid attaining sonic velocity in the impeller or diffuser region of the compressor. The CFD predicted results showed a fair comparison with the experimental results of pressure ratio, power, and efficiency at different speeds.
A Nonlinear Dynamic Reduced-Order Model for a Large Gas Turbine Outer Casing Low Cycle Fatigue Prediction
Authors: Dubey Aditya , Relan Rishi , Lohse Uwe , Szwedowicz Jaroslaw 
Published: December 2021

Abstract
The secondary stresses that result from nonlinear and transient thermal gradients during the start-up and shut down of the large gas turbine engines drive low-cycle fatigue at specific locations of the outer casing. Typical service inspection of the outer casing is primarily based on finite element analysis estimates, considering various safety factors. However, as finite element analysis includes the worst possible combination of loading scenarios and operating conditions any engine may encounter in actual operation, this results in a conservative estimation of the service interval. Therefore, a generic preventive maintenance plan for the whole fleet often underutilises the casing capability and added cost. Hence, this paper proposes a data-driven nonlinear dynamic reduced-order model developed using the temperature data from low-cycle fatigue critical casing locations, ramp rates, and the percentage load of operation to predict the stresses. As a result, a reduced-order model can assess the damage for low-cycle fatigue critical locations in real-time using the operational data and propose an appropriate service intervention plan for each casing in a fleet.
Comparative Study of Barrier Coatings on Turbine Blade Cooling
Authors: Singh Kishan A. , Labana Zozimus D. 
Published: December 2021

Abstract
There is a continuous growth in various sectors of engineering and technology resulting in high demand for modern and innovative steps into providing solutions to overcome all barriers. With the increase in demand of modern age technology growing rapidly, the requirement of the advanced system has to keep up with this demand. The power required to drive such technology has one of its sources from the gas turbine propulsion system, which is capable to provide thrust and power to major components. In modern gas turbine applications, high power and thermal efficiency are of essential requirement. The two parameters that play a vital role in increasing the thermal efficiency of the gas turbine are its compression ratio and high turbine inlet temperature. The advanced gas turbine has inlet temperature, which exceeds the material thermal limitation of the blade. This high temperature has an impact on the performance and life of the blade employed for energy extraction in the turbines. The current study analyzes the methods dealing with increasing the cooling effectiveness of the turbine blade, which are working under very high-temperature hot gases that exit from the combustion chamber. This gas expands into the turbine region by which power is extracted. These high-temperature gases can have a considerable effect on the stresses developed that can lead to failure under the cyclic loading of these hot gases. Cooling effectiveness can increase the system working temperature from 800K up to 1000K inlet. The current research compares the means of reducing the heat transfer and improve cooling effectiveness with the help of the latest improved material coatings such as thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs). The study focuses on the effect of these TBCs and EBCs employed on the surface of the blade. Analysis of results obtained from this conjugate heat transfer (CHT) study has shown good agreement with the experimental data. The comparison revealed the use of the SST k-ω model which was efficient and predicted similar trends as that of the experimental for pressure were as with 3% of deviation for temperature.
Numerical Behaviour of Primary Air Flow Field of a Swirl Injector Under High Pressure and High Temperature Condition
Authors: Rana Rampada , Nagalingam Muthuveerappan , Basu Saptarshi 
Published: December 2021

Abstract
Injector plays pivotal role to meet better combustion performances requirements in terms of combustion efficiency, flame stability, ignition, lower emissions etc. In a multi-swirler injector, the primary swirler mainly dictates the airflow field inside and some extend outside the injector. Present CFD studies have been attempted to characterize the flow field of a swirl injector consisting of conical nozzle fitted with single radial swirler at its upstream. Studies are performed at high pressure and high temperature resulting to high density (increased by around 9 times compared to atmospheric condition) and its impact on the flow field in terms of location of energetic zones useful for fuel atomization. Since direct effect of increase in density lead to increase in turbulence which is helpful for mixing and atomization, this study is helpful to capture the same. Embedded LES based hybrid model has been used where the computational domain divided into 3 zones which are seamlessly connected by capturing the interface fluid dynamics. In LES zone, both the time and spatial scales have been resolved by suitably refining the grids. Analysis is carried out with CFL no. around 2, fixed time step of 1 micro second. The analysis is reasonably able to capture various unsteadiness (PVC, CTRZ, frequencies etc. useful for the atomization of the liquid fuel) which are not available beforehand.
Becoming an Occupation? A Research Agenda Into the Professionalization of the Sport for Development and Peace Sector
Authors: McSweeney Mitchell , Millington Rob , Hayhurst Lyndsay M.C. , Darnell Simon 
Published: December 2021

Sport for Development and Peace (SDP) has transformed from what some termed a “social movement” to an institutionalized sector with numerous organizations and practitioners involved, resulting in trends that point toward SDP becoming a recognized category of work through professional training. The purpose of this paper is to utilize theories of professions and institutional isomorphism to advance the significance and importance of thinking about SDP as a profession. Three emerging trends that point to the professionalization of SDP are reviewed: (a) increasing opportunities to attain SDP certifications and training, (b) the growing number of SDP-specific academic degrees, and (c) the creation of a SDP knowledge base, particularly in relation to monitoring and evaluation. To conclude, theoretical and practical implications of the professionalization of SDP are discussed and a research agenda is outlined for future research on the continued institutionalization, and professionalization, of the SDP sector.
Whole-lithosphere shear during oblique rifting
Authors: Lutz Brandon M. , Axen Gary J. , van Wijk Jolante W. , Phillips Fred M. 
Published: December 2021

Abstract
Processes controlling the formation of continental whole-lithosphere shear zones are debated, but their existence requires that the lithosphere is mechanically coupled from base to top. We document the formation of a dextral, whole-lithosphere shear zone in the Death Valley region (DVR), southwest United States. Dextral deflections of depth gradients in the lithosphere-asthenosphere boundary and Moho are stacked vertically, defining a 20–50-km-wide, lower lithospheric shear zone with ~60 km of shear. These deflections underlie an upper-crustal fault zone that accrued ~60 km of dextral slip since ca. 8–7 Ma, when we infer that whole-lithosphere shear began. This dextral offset is less than net dextral offset on the upper-crustal fault zone (~90 km, ca. 13–0 Ma) and total upper-crustal extension (~250 km, ca. 16–0 Ma). We show that, before ca. 8–7 Ma, weak middle crust decoupled upper-crustal deformation from deformation in the lower crust and mantle lithosphere. Between 16 and 7 Ma, detachment slip thinned, uplifted, cooled, and thus strengthened the middle crust, which is exposed in metamorphic core complexes collocated with the whole-lithosphere shear zone. Midcrustal strengthening coupled the layered lithosphere vertically and therefore enabled whole-lithosphere dextral shear. Where thick crust exists (as in pre–16 Ma DVR), midcrustal strengthening is probably a necessary condition for whole-lithosphere shear.
Two-step versus 1-step subretinal injection to compare subretinal drug delivery: a randomised study protocol
Authors: Simunovic Matthew P , Shao Emily H , Osaadon Perach , Sasongko Muhammad Bayu , Too Lay Khoon 
Published: December 2021

IntroductionThere is increasing interest in subretinal injections as a surgical procedure, largely as a result of emerging treatments for ocular diseases which necessitate this manoeuvre. However, surgical variables in the efficacy of such treatments have to date been largely overlooked and the proportion of drug which reaches the intended compartment of the subretinal space remains unknown. Our aims are twofold: first, to determine the proportion of subretinally injected medication retained following surgical delivery and second, to compare two different techniques of injection (‘1-step’ vs ‘2-step’).MethodsWe outline a randomised controlled trial of subretinal injection of alteplase following vitrectomy for the management of submacular haemorrhage secondary to age-related macular degeneration. Patients will be randomised to receive either 1-step injection, where the therapeutic solution simultaneously defines the surgical plane or 2-step injection, where the surgical plane is first identified with balanced salt solution prior to injection of subretinal alteplase, as outlined below. Sodium fluorescein will be used as an optical label to track drug reflux into the vitreous cavity using quantitative protocols established in our laboratory. All patients will undergo fluid air exchange at the completion of surgery, with injection of bevacizumab 1.25 mg and 20% sulfahexafluoride gas as the vitreous substitute (both of which may help improve outcomes). Alteplase, sodium fluorescein and bevacizumab will all be used for off-label indications in the trial.Ethics and disseminationEthical approval has been obtained from the South Eastern Sydney Local Health District’s Human Research Ethics Committee (HREC 17/092). The results of this trial will be disseminated in peer-reviewed proceedings (associated with conference presentation) and in scholarly journals.Trial registration numberACTRN12619001121156.
Cross-sectional study on the characteristics of unrecorded alcohol consumption in nine newly independent states between 2013 and 2017
Authors: Probst Charlotte , Manthey Jakob , Ferreira-Borges Carina , Neufeld Maria , Rakovac Ivo , Andreasyan Diana , Sturua Lela , Novik Irina , Hagverdiyev Gahraman , Obreja Galina , Altymysheva Nurila , Ergeshov Muhammet , Shukrov Shukhrat , Saifuddinov Safar , Rehm Jürgen 
Published: December 2021

ObjectivesAs unrecorded alcohol use contributes to a substantial burden of disease, this study characterises this phenomenon in newly independent states (NIS) of the former Soviet Union with regard to the sources of unrecorded alcohol, and the proportion of unrecorded of total alcohol consumption. We also investigate associated sociodemographic characteristics and drinking patterns.DesignCross-sectional data on overall and unrecorded alcohol use in the past 7 days from WHO STEPwise Approach to NCD Risk Factor Surveillance (STEPS) surveys. Descriptive statistics were calculated at the country level, hierarchical logistic and linear regression models were used to investigate sociodemographic characteristics and drinking patterns associated with using unrecorded alcohol.SettingNine NIS (Armenia, Azerbaijan, Belarus, Georgia, Kyrgyzstan, Republic of Moldova, Tajikistan, Turkmenistan and Uzbekistan) in the years 2013–2017.ParticipantsNationally representative samples including a total of 36 259 participants.ResultsA total of 6251 participants (19.7%; 95% CI 7.9% to 31.5%) reported alcohol consumption in the past 7 days, 2185 of which (35.1%; 95% CI 8.2% to 62.0%) reported unrecorded alcohol consumption with pronounced differences between countries. The population-weighted average proportion of unrecorded consumption in nine NIS was 8.7% (95% CI 5.9% to 12.4%). The most common type of unrecorded alcohol was home-made spirits, followed by home-made beer and wine. Older (45–69 vs 25–44 years) and unemployed (vs employed) participants had higher odds of using unrecorded alcohol. More nuanced sociodemographic differences were observed for specific types of unrecorded alcohol.ConclusionsThis contribution is the first to highlight both, prevalence and composition of unrecorded alcohol consumption in nine NIS. The observed proportions and sources of unrecorded alcohol are discussed in light of local challenges in policy implementation, especially in regard to the newly formed Eurasian Economic Union (EAEU), as some but not all NIS are in the EAEU.
Design and evaluation of strategies to implement HIV prevention interventions for pregnant women in community pharmacy settings in western Kenya: a mixed-methods study protocol
Authors: Mugambi Melissa Latigo , Baeten Jared M , Kinuthia John , Hauber Brett , Weiner Bryan J , John-Stewart Grace , Barnabas Ruanne Vanessa 
Published: December 2021

IntroductionCommunity pharmacies play an important role in the healthcare system: they are frequently accessed and have increasing capacity to deliver HIV prevention services. In communities where the prevalence of HIV is high and access to antenatal care clinics is delayed or irregular, there is a unique opportunity to leverage pharmacies to enhance early and sustained access to HIV prevention among pregnant women. This study will identify women’s preferences for delivery of HIV prevention services and provider-level and system-level strategies to design a new pharmacy-based model of care for pregnant women. The overall objective of this study is to design and evaluate strategies to implement HIV prevention interventions for pregnant women in community pharmacy settings in western Kenya.Methods and analysisWe propose to conduct a discrete choice experiment to quantify preferences for delivery of HIV prevention interventions (including pre-exposure prophylaxis, partner testing and sexually transmitted infection screening and treatment) for pregnant women in community pharmacy settings. Latent class analysis will be used to quantify women’s stated preferences and identify packages of intervention components that will optimise uptake among different subgroups of women. We will apply the Theoretical Domains Framework to identify provider-level and system-level factors that might influence the implementation of the optimal intervention packages. We will then use the Behaviour Change Wheel and survey a panel of experts to select and gain consensus on strategies to improve implementation. Finally, we will evaluate the potential costs of extending the implementation of HIV prevention interventions from the clinic to community pharmacy settings.Ethics and disseminationThe protocol was approved by the Kenyatta National Hospital-University of Nairobi Ethics Research Committee and the University of Washington Institutional Review Board. The results of this research will be published in peer-reviewed journals and shared with various stakeholders, including community members, policymakers and researchers, through local and international conferences.
Impact of Medicare prescription drug (Part D) coverage expansion on utilisation and financial burden of benzodiazepines among older adults: an interrupted time series analysis
Authors: Li Minghui , Yuan Jing , Dezfuli Chelsea , Lu Z Kevin 
Published: December 2021

ObjectiveBenzodiazepines were excluded from Medicare Part D coverage since its introduction in 2006. Part D expanded coverage for benzodiazepines in 2013. The objective was to examine the impact of Medicare Part D coverage expansion on the utilisation and financial burden of benzodiazepines in older adults.DesignInterrupted time series with a control group.SettingNationally representative sample.Participants53 150 468 users of benzodiazepines and 21 749 749 users of non-benzodiazepines (an alternative therapy) from the Medicare Current Beneficiary Survey between the pre-expansion (2006–2012) and post-expansion (2013–2017) periods.InterventionMedicare Part D coverage expansion on benzodiazepines.Primary and secondary outcome measuresAnnual rate of benzodiazepines and non-benzodiazepines, average number of benzodiazepines and non-benzodiazepines and average cost of benzodiazepines and non-benzodiazepines.ResultsAfter Medicare Part D coverage expansion, the level of the annual rate of benzodiazepines increased by 8.20% (95% CI: 6.07% to 10.32%) and the trend decreased by 1.03% each year (95% CI: −1.77% to −0.29%). The trend of the annual rate of non-benzodiazepines decreased by 0.72% each year (95% CI: −1.11% to −0.33%). For the average number of benzodiazepines, the level increased by 0.67 (95% CI: 0.52 to 0.82) and the trend decreased by 0.10 each year (95% CI: −0.15 to –0.05). For the average number of non-benzodiazepines, the level decreased by 0.11 (95% CI: −0.21 to –0.01) and the trend decreased by 0.04 each year (95% CI: −0.08 to –0.01). No significant level and trend changes were identified for the average cost of benzodiazepines and non-benzodiazepines.ConclusionsAfter Medicare Part D coverage expansion, there was a sudden increase in the utilisation of benzodiazepines and a decreasing trend in the long-term. The increase in the utilisation of benzodiazepines did not add a financial burden to older adults. As an alternative therapy, the utilisation of non-benzodiazepines decreased following the coverage expansion.
Gender-specific prevalence of metabolic-associated fatty liver disease among government employees in Tianjin, China: a cross-sectional study
Authors: Huang Ya-Ping , Zhang Shi , Zhang Minying , Wang Yi , Wang Wen-Hong , Li Jing , Li Chunjun , Lin Jing-Na 
Published: December 2021

ObjectivesTo explore the prevalence and risk factors of metabolic-associated fatty liver disease (MAFLD) in Tianjin government employees of different genders.DesignCross-sectional study.SettingHealth Management Center of Tianjin Union Medical Center.Participants16 924 government employees (59.6% male).MeasuresUltrasound liver examination was performed to determine whether there is fat accumulation in the organ. Participants’ weight and height were measured, and body mass index (BMI) was calculated.ResultsThe overall prevalence of MAFLD in this population was 40.76%. The rates were significantly higher in men (49.42%) than in women (27.97%). The prevalence of MAFLD was highest in men aged 40–49 years (54.04%) and women aged 60–69 years (43.44%). In all BMI groups, the prevalence was higher in men than that in women. In both genders, higher BMI was associated with the risk of MAFLD, especially for BMI ≥31.9 kg/m2.ConclusionsThe prevalence of MAFLD in government employees in Tianjin was significantly higher than the average level in China. The prevalence varied by sex and age group, and those with high BMI were at the highest risk of developing MAFLD.
Women’s experiences of the Odon Device to assist vaginal birth and participation in intrapartum research: a qualitative study in a maternity unit in the Southwest of England
Authors: Hotton Emily J , Blencowe Natalie S , Lenguerrand Erik , Draycott Tim J , Crofts Joanna F , Wade Julia 
Published: December 2021

ObjectiveTo investigate women’s experiences of having a birth assisted by the Odon Device (an innovative device for assisted vaginal birth) and participation in intrapartum research.DesignQualitative semistructured interviews and observations undertaken in the context of case study work embedded in the ASSIST feasibility study.SettingA tertiary referral National Health Service (NHS) maternity unit in the Southwest of England, between 8 October 2018 and 26 January 2019.ParticipantsEight women, four operators and 11 midwives participated with eight observations of the assisted vaginal birth, eight interviews with women in the postnatal period, 39 interviews/reflections with operators and 19 interviews with midwives. Women in the case study research were recruited from participants in the main ASSIST Study.InterventionThe Odon Device, an innovative device for assisted vaginal birth.ResultsThirty-nine case studies were undertaken. Triangulation of data sources (participant observation, interviews with women, operators and midwives) enabled the exploration of women’s experiences of the Odon Device and recruitment in the intrapartum trial. Experiences were overwhelmingly positive. Women were motivated to take part by a wish for a kinder birth, and because they perceived both the recruitment and research processes (including observation) to be highly acceptable, regardless of whether the Odon-assisted birth was successful or not.ConclusionsInterviews and observations from multiple stakeholders enabled insight into women’s experiences of an innovative device for assisted vaginal birth. Applying these qualitative methods more broadly may illuminate perspectives of key stakeholders in future intrapartum intervention research and beyond.Trial registration numberISRCTN10203171;ASSIST Study registration;https://doi.org/10.1186/ISRCTN10203171.