bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-Hole Characteristic Interface and Film Cooling Interface Model
Authors: Zhang Zhen , Li Hui , Su Xinrong , Yuan Xin 
Published: April 2021

Abstract
The performance of film cooling is influenced by many parameters, and the nonuniform flow caused by the internal cooling system is found to largely affect the film cooling, which further complicates the in-hole flow and draws new difficulties in predicting the cooling performance. In this study, we find a very interesting phenomenon that there always exists an in-hole interface, on which distributions of many parameters, including the velocity and kinetic energy, are seldom affected by the mainstream. The existence of this specific interface can be observed for both cylindrical and shaped film cooling holes under most operating conditions. The theoretical analysis of this interface is conducted in this study based on the characteristic decomposition of the Navier–Stokes equation, and this interface is named as the characteristic interface. Theoretical analysis and numerical observations suggest the film cooling system can be simplified to two weakly coupled regions separated by this interface. It also explains why existing source term models for film cooling may fail. Based on these findings, a new prediction model is developed, which uses the convolutional neural networks (CNN) model to predict the boundary conditions on the characteristic interface. The new model outperforms existing source term models and yields similar accuracy as full-mesh computational fluid dynamics (CFD), while reducing the computational cost by one order of magnitude. This model is further evaluated in large eddy simulation (LES), showing moderate success. To sum up, the current work reports the characteristic interface phenomenon in the film cooling hole, based on which a new and efficient prediction model is developed and verified.
Serrated Chip Formation Induced Periodic Distribution of Morphological and Physical Characteristics in Machined Surface During High-Speed Machining of Ti6Al4V
Authors: Xu Binbin , Zhang Jun , Liu Hongguang , Xu Xiang , Zhao Wanhua 
Published: April 2021

Abstract
Difficult-to-cut materials are widely used in aerospace and other industries. Titanium alloys are the most popular ones among them due to their high strength-to-weight ratio and high temperature resistance. However, in high-speed machining, the alloys are prone to produce serrated chips, which have a serious influence on surface integrity. In this study, a coupled Eulerian–Lagrangian method is used to simulate the orthogonal cutting of Ti6Al4V due to its advantages of avoiding element distortion and improving the data extraction efficiency. The internal relationship between serrated chip formation and periodic profile of machined surfaces is analyzed by the simulation results and experimental data which are obtained by optical microscope and white light interferometer. Furthermore, thermal–mechanical loads on machined surfaces are reconstructed based on the simulation results, and a coupled finite element and cellular automata approach is used to describe the dynamic recrystallization process within the area of the machined surface during the formation of a single serration. According to the results, the periodic fluctuation of cutting forces is attributed to the serrated chip formation phenomenon, which then leads to the periodic profile of machined surfaces. The period is about 60–70 µm, and its amplitude decreases with the increase of cutting speeds. Moreover, the loads on machined surfaces also show the same period due to serrated chip formation. As a result, the grain refinement layer thickness (about 2 ∼ 5 µm) in machined surfaces is related to the surface temperature and exhibits the same periodic characteristics along the cutting direction.
Post-covid syndrome in individuals admitted to hospital with covid-19: retrospective cohort study
Authors: Ayoubkhani Daniel , Khunti Kamlesh , Nafilyan Vahé , Maddox Thomas , Humberstone Ben , Diamond Ian , Banerjee Amitava 
Published: April 2021

AbstractObjectiveTo quantify rates of organ specific dysfunction in individuals with covid-19 after discharge from hospital compared with a matched control group from the general population.DesignRetrospective cohort study.SettingNHS hospitals in England.Participants47 780 individuals (mean age 65, 55% men) in hospital with covid-19 and discharged alive by 31 August 2020, exactly matched to controls from a pool of about 50 million people in England for personal and clinical characteristics from 10 years of electronic health records.Main outcome measuresRates of hospital readmission (or any admission for controls), all cause mortality, and diagnoses of respiratory, cardiovascular, metabolic, kidney, and liver diseases until 30 September 2020. Variations in rate ratios by age, sex, and ethnicity.ResultsOver a mean follow-up of 140 days, nearly a third of individuals who were discharged from hospital after acute covid-19 were readmitted (14 060 of 47 780) and more than 1 in 10 (5875) died after discharge, with these events occurring at rates four and eight times greater, respectively, than in the matched control group. Rates of respiratory disease (P<0.001), diabetes (P<0.001), and cardiovascular disease (P<0.001) were also significantly raised in patients with covid-19, with 770 (95% confidence interval 758 to 783), 127 (122 to 132), and 126 (121 to 131) diagnoses per 1000 person years, respectively. Rate ratios were greater for individuals aged less than 70 than for those aged 70 or older, and in ethnic minority groups compared with the white population, with the largest differences seen for respiratory disease (10.5 (95% confidence interval 9.7 to 11.4) for age less than 70 yearsv4.6 (4.3 to 4.8) for age ≥70, and 11.4 (9.8 to 13.3) for non-whitev5.2 (5.0 to 5.5) for white individuals).ConclusionsIndividuals discharged from hospital after covid-19 had increased rates of multiorgan dysfunction compared with the expected risk in the general population. The increase in risk was not confined to the elderly and was not uniform across ethnicities. The diagnosis, treatment, and prevention of post-covid syndrome requires integrated rather than organ or disease specific approaches, and urgent research is needed to establish the risk factors.
Regional differences in the care and outcomes of acute stroke patients in Australia: an observational study using evidence from the Australian Stroke Clinical Registry (AuSCR)
Authors: Dwyer Mitchell , Francis Karen , Peterson Gregory M , Ford Karen , Gall Seana , Phan Hoang , Castley Helen , Wong Lillian , White Richard , Ryan Fiona , Arthurson Lauren , Kim Joosup , Cadilhac Dominique A , Lannin Natasha A 
Published: April 2021

ObjectiveTo compare the processes and outcomes of care in patients who had a stroke treated in urban versus rural hospitals in Australia.DesignObservational study using data from a multicentre national registry.SettingData from 50 acute care hospitals in Australia (25 urban, 25 rural) which participated in the Australian Stroke Clinical Registry during the period 2010–2015.ParticipantsPatients were divided into two groups (urban, rural) according to the Australian Standard Geographical Classification Remoteness Area classification. Data pertaining to 28 115 patients who had a stroke were analysed, of whom 8159 (29%) were admitted to hospitals located within rural areas.Primary and secondary outcome measuresRegional differences in processes of care (admission to a stroke unit, thrombolysis for ischaemic stroke, discharge on antihypertensive medication and provision of a care plan), and survival analyses up to 180 days and health-related quality of life at 90–180 days.ResultsCompared with those admitted to urban hospitals, patients in rural hospitals less often received thrombolysis (urban 12.7% vs rural 7.5%, p<0.001) or received treatment in stroke units (urban 82.2% vs rural 76.5%, p<0.001), and fewer were discharged with a care plan (urban 61.3% vs rural 44.7%, p<0.001). No significant differences were found in terms of survival or overall self-reported quality of life.ConclusionsRural access to recommended components of acute stroke care was comparatively poorer; however, this did not appear to impact health outcomes at approximately 6 months.
Association between primary care physician diagnostic knowledge and death, hospitalisation and emergency department visits following an outpatient visit at risk for diagnostic error: a retrospective cohort study using medicare claims
Authors: Gray Bradley M , Vandergrift Jonathan L , McCoy Rozalina G , Lipner Rebecca S , Landon Bruce E 
Published: April 2021

ObjectiveDiagnostic error is a key healthcare concern and can result in substantial morbidity and mortality. Yet no study has investigated the relationship between adverse outcomes resulting from diagnostic errors and one potentially large contributor to these errors: deficiencies in diagnostic knowledge. Our objective was to measure that associations between diagnostic knowledge and adverse outcomes after visits to primary care physicians that were at risk for diagnostic errors.Setting/participants1410 US general internists who recently took their American Board of Internal Medicine Maintenance of Certification (ABIM-IM-MOC) exam treating 42 407 Medicare beneficiaries who experienced 48 632 ‘index’ outpatient visits for new problems at risk for diagnostic error because the presenting problem (eg, dizziness) was related to prespecified diagnostic error sensitive conditions (eg, stroke).Outcome measures90-day risk of all-cause death, and, for outcome conditions related to the index visits diagnosis, emergency department (ED) visits and hospitalisations.DesignUsing retrospective cohort study design, we related physician performance on ABIM-IM-MOC diagnostic exam questions to patient outcomes during the 90-day period following an index visit at risk for diagnostic error after controlling for practice characteristics, patient sociodemographic and baseline clinical characteristics.ResultsRates of 90-day adverse outcomes per 1000 index visits were 7 for death, 11 for hospitalisations and 14 for ED visits. Being seen by a physician in the top versus bottom third of diagnostic knowledge during an index visit for a new problem at risk for diagnostic error was associated with 2.9 fewer all-cause deaths (95% CI −5.0 to −0.7, p=0.008), 4.1 fewer hospitalisations (95% CI −6.9 to −1.2, p=0.006) and 4.9 fewer ED visits (95% CI −8.1% to −1.6%, p=0.003) per 1000 visits.ConclusionHigher diagnostic knowledge was associated with lower risk of adverse outcomes after visits for problems at heightened risk for diagnostic error.
Predicting mortality in acute ischaemic stroke treated with mechanical thrombectomy: analysis of a multicentre prospective registry
Authors: Li Hao , Ye Shi-sheng , Wu Yuan-Ling , Huang Sheng-Ming , Li Yong-Xin , Lu Kui , Huang Jing-Bo , Chen Lve , Li Hong-Zhuang , Wu Wen-Jun , Wu Zhi-Lin , Wu Jian-Zhou , Zhong Wang-Tao , Xian Wen-Chuan , Liao Feng , Tung Tao-Hsin , Wu Qiao-Ling , Chen Hai , Yuan Li , Yang Zhi , Huang Li-An 
Published: April 2021

ObjectivesWe aimed to determine predictors of mortality within 90 days and develop a simple score for patients with mechanical thrombectomy (MT).DesignAnalysis of a multicentre prospective registry.SettingIn six participating centres, patients who had an acute ischaemic stroke (AIS) treated by MT between March 2017 and May 2018 were documented prospectively.Participants224 patients with AIS were treated by MT.ResultsOf 224 patients, 49 (21.9%) patients died, and 87 (38.8%) were independent. Variables associated with 90-day mortality were age, previous stroke, admission National Institutes of Health Stroke Scale (NIHSS), fasting blood glucose and occlusion site. Logistic regression identified four variables independently associated with 90-day mortality: age ≥80 years (OR 3.26, 95% CI 1.45 to 7.33), previous stroke (OR 2.33, 95% CI 1.04 to 5.21), admission NIHSS ≥18 (OR 2.37, 95% CI 1.13 to 4.99) and internal carotid artery or basilar artery occlusion (OR 2.92, 95% CI 1.34 to 6.40). Using these data, we developed predicting 90-day mortality of AIS with MT (PRACTICE) score ranging from 0 to 6 points. The receiver operator curve analysis found that PRACTICE score (area under the curve (AUC)=0.744, 95% CI 0.669 to 0.820) was numerically better than iScore (AUC=0.661, 95% CI 0.577 to 0.745) and Predicting Early Mortality of Ischemic Stroke score (AUC=0.638, 95% CI 0.551 to 0.725) for predicting 90-day mortality.ConclusionsWe developed a simple score to estimate the 90-day mortality of patients who had an AIS treated with MT. But the score needs to be prospectively validated.Trial registration numberChinese Clinical Trial Registry (ChiCTR-OOC-17013052).
Translating the Symptom Screening in Pediatrics Tool (SSPedi) into Argentinian Spanish for paediatric patients receiving cancer treatments, and evaluating understandability and cultural relevance in a multiple-phase descriptive study
Authors: Gomez Sergio , Salaverria Carmen , Plenert Erin , Gonzalez Gisela , D'Angelo Gisela , Grimes Allison , Sugalski Aaron , Langevin Anne-Marie , Dupuis Lee , Sung Lillian 
Published: April 2021

ObjectivesTo translate a symptom screening tool developed for paediatric patients receiving cancer therapies called Symptom Screening in Pediatrics Tool (SSPedi) into Argentinian Spanish and to evaluate the understandability and cultural relevance of the translated version of SSPedi among children with cancer and paediatric haematopoietic stem cell transplant (HSCT) recipients.MethodsWe conducted a multiphase, descriptive study to translate SSPedi into Argentinian Spanish. Using two translators, forward and backward translations were performed. The translated version was evaluated by Spanish-speaking paediatric patients 8–18 years of age receiving cancer treatments in two centres in Argentina and El Salvador.Primary and secondary outcome measuresThe primary outcome was patient self-reported difficulty with understanding of the SSPedi instructions and each symptom using a 5-point Likert scale. Secondary outcomes were incorrect understanding of the SSPedi instructions, symptoms and response scale determined by cognitive interviews with the patients and rated using a 4-point Likert scale. Cultural relevance was assessed qualitatively.ResultsThere were 30 children enrolled and included in cognitive interviews; 16 lived in Argentina and 14 lived in El Salvador. The most common types of Spanish spoken were Central American (17, 57%) followed by South American (10, 33%) and Castilian (3, 10%). No changes to Argentinian Spanish SSPedi were required based on the outcomes or qualitative comments. No issues with cultural relevance were identified by any of the respondents.ConclusionsWe translated and finalised Argentinian Spanish SSPedi. Future research will focus on its use to describe bothersome symptoms by Argentinian Spanish-speaking children.
Variables associated with COVID-19 severity: an observational study of non-paediatric confirmed cases from the general population of the Basque Country, Spain
Authors: Vrotsou Kalliopi , Rotaeche Rafael , Mateo-Abad Maider , Machón Mónica , Vergara Itziar 
Published: April 2021

ObjectivesTo investigate which were the most relevant sociodemographic and clinical variables associated with COVID-19 severity, and uncover how their inter-relations may have affected such severity.DesignA retrospective observational study based on electronic health record data.ParticipantsIndividuals ≥14 years old with a positive PCR or serology test, between 28 February and 31 May 2020, belonging to the Basque Country (Spain) public health system. Institutionalised and individuals admitted to a hospital at home unit were excluded from the study.Main outcome measureThree severity categories were established: primary care, hospital/intensive care unit admission and death.ResultsA total of n=14 197 cases fulfilled the inclusion criteria. Most variables presented statistically significant associations with the outcome (p<0.0001). The Classification and Regression Trees recursive partitioning methodology (based on n=13 792) suggested that among all associations, those with, age, sex, stratification of patient healthcare complexity, chronic consumption of blood and blood-forming organ, and nervous system drugs, as well as the total number of chronic Anatomical Therapeutic Chemical types were the most relevant. Psychosis also emerged as a potential factor.ConclusionsOlder cases are more likely to experience more severe outcomes. However, the sex, underlying health status and chronic drug consumption may interfere and alter the ageing effect. Understanding the factors related to the outcome severity is of key importance when designing and promoting public health intervention plans for the COVID-19 pandemic.
Hydroxychloroquine treatment in European patients with lupus erythematosus: dosing, retinopathy screening and adherence
Authors: Osmani Zgjim , Schrama Thijs J , Zacouris-Verweij Wendy , Andersen Jeanette , Frankel Susan , Bultink Irene E M , Cornet Alain , van Vollenhoven Ronald F 
Published: April 2021

BackgroundUse of hydroxychloroquine (HCQ) is common in patients with lupus erythematosus. Long-term use (ie, ≥5 years) and high-dose HCQ (ie, >5 mg/kg/day) are both risk factors for developing HCQ retinopathy. Advances in our understanding of HCQ retinopathy have led to changes in the recommendations for HCQ dosing and retinopathy screening. The latest EULAR guidelines for the management of SLE recommend a maximum HCQ dose of 5 mg/kg/day and ophthalmological screening at baseline and annually after 5 years of HCQ treatment.ObjectivesThis study aimed to assess whether the EULAR guidelines are affecting HCQ prescription patterns and screening frequencies in Europe. Furthermore, we inventoried adherence to HCQ.ResultsThe online questionnaire was completed by 2936 patients with systemic, cutaneous or juvenile lupus from 33 countries. The majority were female (86.5%) and diagnosed with SLE (81.2%). Among those taking HCQ, the median HCQ dose reported was 4.26 mg/kg/day. More than one-third of respondents (36.8%) exceeded the recommended maximal HCQ dose of 5 mg/kg/day. Baseline ophthalmological screening had been done in 857 out of 1017 respondents diagnosed in the past 10 years (84.3%). Of patients using HCQ ≥5 years, 69.2% reported yearly retinopathy screening. Lastly, 17.3% of patients reported that they skipped HCQ once a week or more often.ConclusionThe results of our study demonstrate that higher than recommended dosages of HCQ are prescribed to more than one-third of patients with lupus in Europe. Recent recommendations regarding screening for retinopathy are incompletely implemented.
Haemostatic therapy in spontaneous intracerebral haemorrhage patients with high-risk of haematoma expansion by CT marker: a systematic review and meta-analysis of randomised trials
Authors: Nie Ximing , Liu Jingyi , Liu Dacheng , Zhou Qi , Duan Wanying , Pu Yuehua , Yang Zhonghua , Wen Miao , Sun Haixin , Wang Wenzhi , Sun Shengjun , Gu Hongqiu , Liu Liping 
Published: April 2021

Background and purposeCurrent randomised controlled trials (RCTs) showed an uncertain benefit of haemostatic therapy on preventing haematoma expansion and improving the outcome in patients with intracerebral haemorrhage (ICH). This meta-analysis aims to systematically evaluate the effect of haemostatic agents on the prevention of haemorrhage growth in patients with high-risk spontaneous ICH predicted by CT signs in RCTs.MethodsA comprehensive search of PubMed, EMBASE and Cochrane library from 1 January 2005 to 30 June 2021 was conducted. RCTs that compared haemostatic agents with placebo for the treatment of spontaneous patients with ICH with high-risk haemorrhage growth were included. The primary endpoint was haematoma expansion at 24 hours. Other major endpoints of interest included 90-day functional outcome and mortality.ResultsThe meta-analysis included four RCTs that randomised 2666 patients with ICH with high-risk haemorrhage growth. Haemostatic therapy reduced the rate of haematoma expansion at a marginally statistically significant level when compared with placebo (OR 0.84; 95% CI 0.70 to 1.00; p=0.051). Subgroup analysis for patients with black hole sign on CT revealed a significant reduction of haematoma expansion with haemostatic therapy (OR 0.61; 95% CI 0.39 to 0.94; p=0.03). However, both the primary analysis and subgroup analyses showed that haemostatic therapy could not reduce the rate of poor functional outcome (modified Rankin Scale >3) or death.ConclusionsHaemostatic therapy showed a marginally significant benefit in reducing early haematoma expansion in patients with high-risk spontaneous ICH predicted by markers on CT scan. However, no significant improvement in functional outcome or reduction of mortality was observed.
Tranexamic acid for acute intracerebral haemorrhage growth based on imaging assessment (TRAIGE): a multicentre, randomised, placebo-controlled trial
Authors: Liu Jingyi , Nie Ximing , Gu Hongqiu , Zhou Qi , Sun Haixin , Tan Ying , Liu Dacheng , Zheng Lina , Zhao Jiahui , Wang Yan , Cao Yibin , Zhu Haomeng , Zhang Yunpeng , Yi Lijin , Pu Yuehua , Wen Miao , Yang Zhonghua , Sun Shengjun , Wang Wenzhi , Zhao Xingquan , Liu Liping , Wang Yongjun 
Published: April 2021

BackgroundStudies show tranexamic acid can reduce the risk of death and early neurological deterioration after intracranial haemorrhage. We aimed to assess whether tranexamic acid reduces haematoma expansion and improves outcome in intracerebral haemorrhage patients susceptible to haemorrhage expansion.MethodsWe did a prospective, double-blind, randomised, placebo-controlled trial at 10 stroke centres in China. Acute supratentorial intracerebral haemorrhage patients were eligible if they had indication of haemorrhage expansion on admission imaging (eg, spot sign, black hole sign or blend sign), and were treatable within 8 hours of symptom onset. Patients were randomly assigned (1:1) to receive either tranexamic acid or a matching placebo. The primary outcome was intracerebral haematoma growth (>33% relative or >6 mL absolute) at 24 hours. Clinical outcomes were assessed at 90 days.ResultsOf the 171 included patients, 124 (72.5%) were male, and the mean age was 55.9±11.6 years. 89 patients received tranexamic acid and 82 received placebo. The primary outcome did not differ significantly between the groups: 36 (40.4%) patients in the tranexamic acid group and 34 (41.5%) patients in the placebo group had intracranial haemorrhage growth (OR 0.96, 95% CI 0.52 to 1.77, p=0.89). The proportion of death was lower in the tranexamic acid treatment group than placebo group (8.1% vs 10.0%), but there were no significant differences in secondary outcomes including absolute intracranial haemorrhage growth, death and dependency.ConclusionsAmong patients susceptible to haemorrhage expansion treated within 8 hours of stroke onset, tranexamic acid did not significantly prevent intracerebral haemorrhage growth. Larger studies are needed to assess safety and efficacy of tranexamic acid in intracerebral haemorrhage patients.
COVID-19 pandemic − Inequities and inequalities to exercise and their consequences on the physical and mental health of women with cardiovascular disease: recommendations on how to address the needs of women
Authors: O’Neill C.D. , Vidal-Almela S. , Tulloch H.E. , Coutinho T. , Prince S.A. , Reed J.L. 
Published: April 2021

The coronavirus disease (COVID-19) pandemic disproportionately affects those with pre-existing conditions and has exacerbated gender inequalities. Cardiovascular disease (CVD) is the leading cause of death among Canadian women. Exercise improves physical and mental health and CVD management. Amid the pandemic, women are experiencing an increase in caregiving responsibilities, job insecurities, and domestic violence creating competing demands for prioritizing their health. Recommendations on how to meet the unique needs of Canadian women with CVD through exercise are provided. Novelty: Exercise recommendations amid the pandemic for women with CVD need to be flexible, feasible, and fun.