bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Simulations and Validation of Engine Performance Parameter in Direct Injection Spark Ignition (DISI) Engines Using Chemical Kinetics
Authors: Arshad Muzammil 
Published: February 2021

Abstract
Experimental studies have been augmented by computer modelling and simulations for the development and optimization of future fuels and automotive engines. Traditional reliance on the simplified global reactions for combustion simulations reduces the credibility of the prediction of combustion and engine performance parameters, such as in-cylinder pressure, heat release and pollutant formation. The study of engine performance parameters helps in improving the performance as well as the reduction of emissions in the engines. The present study has used detailed chemistry by augmenting the combustion model of a three-dimensional unsteady compressible turbulent Navier-Stokes solver with liquid spray injection by coupling its fluid mechanics solution with detailed kinetic reactions solved by a commercial chemistry solver. A skeletal reaction mechanism was reduced to study the in-cylinder pressure in a direct injection spark ignition (DISI) engine. Sensitivity analysis was performed to reduce the reaction mechanism for the compression and power strokes utilizing computational singular perturbation (CSP) method. An interface was developed between fluid dynamics and chemical kinetics codes to study iso-octane that is a well-established surrogate fuel for gasoline. Gasoline is a complex mixture of various compounds and hydrocarbons. The study used 90% iso-octane and 10% n-heptane as surrogate fuel because this combination best modelled the results. A mesh independent study was performed at stoichiometric conditions that validated and showed a good agreement of peak in-cylinder pressure against the experimental data for a direct injection spark ignition (DISI) engine. This study has been comprehensive as it includes a detailed study performed for premixed case at ϕ = 0.98 and 1.3 as well as stoichiometric condition in a direct injection spark ignition (DISI) engine, that resulted in the development of a reduced mechanism that has the capability to validate in-cylinder pressure and heat release rate from stoichiometric to rich mixtures for premixed cases in a spark ignition engine. The study concludes that it is imperative to establish a library of reduced mechanisms for various spark ignition engines as well as other combustion systems.
Differences in the Manifestation of Cell Pluripotence In Vivo and In Vitro in the Mutant Arabidopsis thaliana with the Phenotype of Cell Memory Disorder
Authors: Kupriyanova E. V. , Denisova E. R. , Baier M. A. , Ezhova T. A. 
Published: February 2021

AbstractPlant cells cultivated in vitro are a convenient model for studying the genetic and physiological mechanisms necessary for the cells to acquire a state of pluripotency. Earlier studies on a model plantArabidopsis thaliana(L.) Heynh. have identified the key role of genes that determine the pluripotency of cells in the shoot apical meristem in de novo shoot regeneration in tissue culture. In accordance with this, cells of mutant plants with a higher level of expression of pluripotency genes were characterized by an increased potential for de novo shoot regeneration. Thetaemutant was the exception to this rule. The mutant resumed the expression of pluripotency genes and cell proliferation at the late stages of leaf development, which indicates a violation of the mechanisms for maintaining epigenetic cellular memory. At the same time, leaf cells cultured in vitro showed a lower proliferative activity compared to the wild type and were not capable of de novo regeneration of shoots. A decrease in the regenerative potential of cultured cells of thetaemutant indicates an important role of epigenetic memory in the response of cells to exogenous hormones. Impaired epigenetic memory of leaf cells of thetae mutant and differences in their proliferative and regenerative capacities in planta and in vitro make this mutant a unique model for studying the role of epigenetic modifications in the regulation of cell pluripotency.
Optimising prediction of early metastasis-free survival in uveal melanoma using a four-category model incorporating gene expression profile and tumour size
Authors: Roelofs Kelsey Andrea , Grewal Parampal , Lapere Steven , Larocque Matthew , Murtha Albert , Weis Ezekiel 
Published: February 2021

BackgroundLargest basal diameter (LBD) appears to have independent prognostic value in uveal melanoma (UM).MethodsAll patients undergoing plaque brachytherapy or enucleation for UM involving the choroid and/or ciliary body between 2012 and 2019.ResultsA total of 348 patients with a mean age of 60±14 years were included and followed for a mean of 40±26 months (3.3±2.2 years). On multivariate analysis, LBD >12 mm remained a significant independent predictor of metastasis for both class 1 (HR 21.90; 95% CI 2.69 to 178.02; p=0.004) and class 2 (HR 2.45; 95% CI, 1.03 to 5.83; p=0.04) tumours. Four prognostic groups were created: group 1 (class 1, LBD <12 mm), group 2 (class 1, LBD ≥12 mm), group 3 (class 2, LBD <12 mm) and group 4 (class 2, LBD ≥12 mm). Life tables were used to calculate the 3-year and 5-year metastasis-free survival: group 1 (98 and 98%), group 2 (86 and 86%), group 3 (81 and 62%) and group 4 (54 and 47%). Compared with the reference category (group 1), the Cox proportional hazard model demonstrated a significant worsening of survival for each progressive category (group 2 (HR 21.59; p=0.004), group 3 (HR 47.12, p<0.001), and group 4 (HR 114.24; p<0.001)). In our dataset, the four-category Cox model performed poorer compared with the American Joint Committee on Cancer (AJCC) and gene expression profile (AJCC+GEP) in the Akaike’s information criteria (AIC) (297 vs 291), fit better with the Bayesian information criteria (BIC) (309 vs 313) and performed similarly with the Harrel’s C (0.86 (95% CI 0.80 to 0.91) vs 0.89 (0.84 to 0.94), respectively).ConclusionsCombination of GEP and LBD allows separation of patients into four easy-to-use prognostic groups and was similar to a model combining AJCC stage with GEP.
Avoiding mask-related artefacts in visual field tests during the COVID-19 pandemic
Authors: Gómez Mariscal Marta , Muñoz-Negrete Francisco José , Muñoz-Ramón Pablo Vicente , Aguado Casanova Victor , Jaumandreu Laia , Rebolleda Gema 
Published: February 2021

AimsTo assess visual field (VF) pseudoprogression related to face mask use.MethodsWe reviewed a total of 307 VFs performed with a face mask (FPP2/KN95 or surgical masks) and compared them with prior VFs, performed before the pandemic. VFs with suspected pseudoprogression due to mask artefacts (VF test 1) were repeated with a surgical mask and an adhesive tape on its superior border (VF test 2) to distinguish from true VF loss. Several parameters including reliability indices, test duration, VF index (VFI), mean defect (MD) and pattern deviation probability plots were compared among last pre-COVID VFs, VF tests 1 and VF tests 2, using the Wilcoxon signed-rank test.ResultsWe identified 18 VFs with suspected progression artefact due to masks (5.8%). In all of them, the median VFI and MD significantly improved after fitting the superior border of the mask, showing no significant differences with pre-COVID tests. The median fixation losses were significantly higher when wearing the unfitted mask (13% vs 6%,p=0.047). The inferior hemifield was the most affected, either as a new scotoma or as an enlargement of a prior defect.ConclusionUnfitted masks can simulate VF progression in around 6% of cases, mainly in the inferior hemifield, and increase significantly the rate of fixation losses. A similar rate of artefacts was observed using FPP2/KN95 or surgical masks. The use of a surgical mask with an adhesive tape covering the superior border may reduce mask-related artefacts, although concomitant progression cannot be ruled out in all cases.
Metabolomics-based multidimensional network biomarkers for diabetic retinopathy identification in patients with type 2 diabetes mellitus
Authors: Zuo Jingjing , Lan Yuan , Hu Honglin , Hou Xiangqing , Li Jushuang , Wang Tao , Zhang Hang , Zhang Nana , Guo Chengnan , Peng Fang , Zhao Shuzhen , Wei Yaping , Jia Chaonan , Zheng Chao , Mao Guangyun 
Published: February 2021

IntroductionDespite advances in diabetic retinopathy (DR) medications, early identification is vitally important for DR administration and remains a major challenge. This study aims to develop a novel system of multidimensional network biomarkers (MDNBs) based on a widely targeted metabolomics approach to detect DR among patients with type 2 diabetes mellitus (T2DM) efficiently.Research design and methodsIn this propensity score matching-based case-control study, we used ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry system for serum metabolites assessment of 69 pairs of patients with T2DM with DR (cases) and without DR (controls). Comprehensive analysis, including principal component analysis, orthogonal partial least squares discriminant analysis, generalized linear regression models and a 1000-times permutation test on metabolomics characteristics were conducted to detect candidate MDNBs depending on the discovery set. Receiver operating characteristic analysis was applied for the validation of capability and feasibility of MDNBs based on a separate validation set.ResultsWe detected 613 features (318 in positive and 295 in negative ESI modes) in which 63 metabolites were highly relevant to the presence of DR. A panel of MDNBs containing linoleic acid, nicotinuric acid, ornithine and phenylacetylglutamine was determined based on the discovery set. Depending on the separate validation set, the area under the curve (95% CI), sensitivity and specificity of this MDNBs system were 0.92 (0.84 to 1.0), 96% and 78%, respectively.ConclusionsThis study demonstrates that metabolomics-based MDNBs are associated with the presence of DR and capable of distinguishing DR from T2DM efficiently. Our data also provide new insights into the mechanisms of DR and the potential value for new treatment targets development. Additional studies are needed to confirm our findings.
Income-based inequalities in self-reported moderate-to-vigorous physical activity among adolescents in England and the USA: a cross-sectional study
Authors: Scholes Shaun , Mindell Jennifer S 
Published: February 2021

ObjectiveQuantify income-based inequalities in self-reported moderate-to-vigorous physical activity (MVPA) in England and the USA by sex.DesignPopulation-based cross-sectional study.Participants4019 adolescents aged 11–15 years in England (Health Survey for England 2008, 2012, 2015) and 4312 aged 12–17 years in the US (National Health and Nutrition Examination Survey 2007–2016).Main outcome measuresThree aspects of MVPA: (1) doing any, (2) average min/day (MVPA: including those who did none) and (3) average min/day conditional on participation (MVPA active). Using hurdle models, inequalities were quantified using the absolute difference in marginal means (average marginal effects).ResultsIn England, adolescents in high-income households were more likely than those in low-income households to have done any formal sports/exercise in the last 7 days (boys: 11%; 95% CI 4% to 17%; girls: 13%; 95% CI 6% to 20%); girls in high-income households did more than their low-income counterparts (MVPA: 6 min/day, 95% CI 2 to 9). Girls in low-income households spent more time in informal activities than girls in high-income households (MVPA: 21 min/day; 95% CI 10 to 33), while boys in low-income versus high-income households spent longer in active travel (MVPA: 21 min/week; 95% CI 8 to 34). In the USA, in a typical week, recreational activity was greater among high-income versus low-income households (boys: 15 min/day; 95% CI 6 to 24; girls: 19 min/day; 95% CI 12 to 27). In contrast, adolescents in low-income versus high-income households were more likely to travel actively (boys: 11%; 95% CI 3% to 19%; girls: 10%; 95% CI 3% to 17%) and do more.ConclusionsPolicy actions and interventions are required to increase MVPA across all income groups in England and the USA. Differences in formal sports/exercise (England) and recreational (USA) activities suggest that additional efforts are required to reduce inequalities.
Association of proton pump inhibitors and concomitant drugs with risk of acute kidney injury: a nested case–control study
Authors: Ikuta Keiko , Nakagawa Shunsaku , Momo Kenji , Yonezawa Atsushi , Itohara Kotaro , Sato Yuki , Imai Satoshi , Nakagawa Takayuki , Matsubara Kazuo 
Published: February 2021

ObjectivesThis study aimed to assess whether the combined use of proton pump inhibitors (PPIs) with non-steroidal anti-inflammatory drugs (NSAIDs) or antibiotics (penicillins, macrolides, cephalosporins or fluoroquinolones) was associated with an increased risk of acute kidney injury (AKI).DesignA nested case–control study.SettingA health insurance claims database constructed by the Japan Medical Data Center.ParticipantsPatients were eligible if they were prescribed a PPI, NSAID and antibiotic at least once between January 2005 and June 2017. The patients who were new PPI users and did not have any history of renal diseases before cohort entry were included (n=219 082). The mean age was 45 and 44% were women.InterventionsCurrent use of PPIs, NSAIDs, or antibiotics.Primary outcome measuresAcute kidney injury.ResultsDuring a mean follow-up of 2.4 (SD, 1.7) years, 317 cases of AKI were identified (incidence rate of 6.1/10 000 person-years). The current use of PPIs was associated with a higher risk of AKI compared with past PPI use (unadjusted OR, 4.09; 95% CI, 3.09 to 5.44). The unadjusted ORs of AKI for the current use of PPIs with NSAIDs, cephalosporins and fluoroquinolones, compared with the current use of PPIs alone, were 3.92 (95% CI, 2.40 to 6.52), 2.57 (1.43 to 4.62) and 3.08 (1.50 to 6.38), respectively. The effects of concurrent use of PPIs with NSAIDs, cephalosporins or fluoroquinolones remain significant in the adjusted model. The analyses on absolute risk of AKI confirmed the results from the nested case–control study.ConclusionsConcomitant use of NSAIDs with PPIs significantly increased the risk for AKI. Moreover, the results suggested that concomitant use of cephalosporins or fluoroquinolones with PPIs was associated with increased risk of incident AKI.
Assessing the regional impact of Japan’s COVID-19 state of emergency declaration: a population-level observational study using social networking services
Authors: Yoneoka Daisuke , Shi Shoi , Nomura Shuhei , Tanoue Yuta , Kawashima Takayuki , Eguchi Akifumi , Matsuura Kentaro , Makiyama Koji , Uryu Shinya , Ejima Keisuke , Sakamoto Haruka , Taniguchi Toshibumi , Kunishima Hiroyuki , Gilmour Stuart , Nishiura Hiroshi , Miyata Hiroaki 
Published: February 2021

ObjectiveOn 7 April 2020, the Japanese government declared a state of emergency in response to the novel coronavirus outbreak. To estimate the impact of the declaration on regional cities with low numbers of COVID-19 cases, large-scale surveillance to capture the current epidemiological situation of COVID-19 was urgently conducted in this study.DesignCohort study.SettingSocial networking service (SNS)-based online survey conducted in five prefectures of Japan: Tottori, Kagawa, Shimane, Tokushima and Okayama.Participants127 121 participants from the five prefectures surveyed between 24 March and 5 May 2020.InterventionsAn SNS-based healthcare system named COOPERA (COvid-19: Operation for Personalized Empowerment to Render smart prevention And care seeking) was launched. It asks questions regarding postcode, personal information, preventive actions, and current and past symptoms related to COVID-19.Primary and secondary outcome measuresEmpirical Bayes estimates of age-sex-standardised incidence rate (EBSIR) of symptoms and the spatial correlation between the number of those who reported having symptoms and the number of COVID-19 cases were examined to identify the geographical distribution of symptoms in the five prefectures.Results97.8% of participants had no subjective symptoms. We identified several geographical clusters of fever with significant spatial correlation (r=0.67) with the number of confirmed COVID-19 cases, especially in the urban centres of prefectural capital cities.ConclusionsGiven that there are still several high-risk areas measured by EBSIR, careful discussion on which areas should be reopened at the end of the state of emergency is urgently required using real-time SNS system to monitor the nationwide epidemic.
Characteristics and practices of school-based cluster randomised controlled trials for improving health outcomes in pupils in the UK: a systematic review protocol
Authors: Parker Kitty , Nunns Michael P , Xiao ZhiMin , Ford Tamsin , Ukoumunne Obioha C 
Published: February 2021

IntroductionCluster randomised trials (CRTs) are studies in which groups (clusters) of participants rather than the individuals themselves are randomised to trial arms. CRTs are becoming increasingly relevant for evaluating interventions delivered in school settings for improving the health of children. Schools are a convenient setting for health interventions targeted at children and the CRT design respects the clustered structure in schools (ie, pupils within classrooms/teachers within schools). Some of the methodological challenges of CRTs, such as ethical considerations for enrolment of children into trials and how best to handle the analysis of data from participants (pupils) that change clusters (schools), may be more salient for the school setting. A better understanding of the characteristics and methodological considerations of school-based CRTs of health interventions would inform the design of future similar studies. To our knowledge, this is the only systematic review to focus specifically on the characteristics and methodological practices of CRTs delivered in schools to evaluate interventions for improving health outcomes in pupils in the UK.Methods and analysisWe will search for CRTs published from inception to 30 June 2020 inclusively indexed in MEDLINE (Ovid). We will identify relevant articles through title and abstract screening, and subsequent full-text screening for eligibility against predefined inclusion criteria. Disagreements will be resolved through discussion. Two independent reviewers will extract data for each study using a prepiloted data extraction form. Findings will be summarised using descriptive statistics and graphs.Ethics and disseminationThis methodological systematic review does not require ethical approval as only secondary data extracted from papers will be analysed and the data are not linked to individual participants. After completion of the systematic review, the data will be analysed, and the findings disseminated through peer-reviewed publications and scientific meetings.PROSPERO registration numberCRD42020201792.
COPD-Lower Respiratory Tract Infection Visual Analogue Score (c-LRTI-VAS) validation in stable and exacerbated patients with COPD
Authors: Prins Hendrik Johannes , Duijkers Ruud , Daniels Johannes M A , van der Molen Thys , van der Werf Tjip S , Boersma Wim 
Published: February 2021

BackgroundWe developed the chronic obstructive pulmonary disease (COPD)-Lower Respiratory Tract Infection-Visual Analogue Score (c-LRTI-VAS) in order to easily quantify symptoms during exacerbations in patients with COPD. This study aimed to validate this score.MethodsIn our study, patients with stable COPD as well as those with an acute exacerbations of COPD (AECOPD) were included. The results of c-LRTI-VAS were compared with other markers of disease activity (lung function parameters, oxygen saturation and two health related quality of life questionnaires (St Georges Respiratory Questionnaire (SGRQ) and Clinical COPD Questionnaire (CCQ)) and validity, reliability and responsiveness were assessed.ResultsEighty-eight patients with clinically stable COPD and 102 patients who had an AECOPD completed the c-LRTI-VAS questionnaire. When testing on two separate occasions for repeatability, no statistically significant difference between total scores was found 0.143 (SD 5.42) (p=0.826). Internal consistency was high across items (Cronbach’s apha 0.755). Correlation with SGRQ and CCQ total scores was moderate to high. After treatment for hospitalised AECOPD, the mean c-LRTI-VAS total score improved 8.14 points (SD 9.13; p≤0.001).Conclusionsc-LRTI-VAS showed proper validity, responsiveness to change and moderate to high correlation with other questionnaires. It, therefore, appears a reliable tool for symptom measurement during AECOPD.Trial registration numberNCT01232140.
Impact of videolaryngoscopy introduction into prehospital emergency medicine practice: a quality improvement project
Authors: Steel Alistair , Haldane Charlotte , Cody Dan 
Published: February 2021

IntroductionAdvanced airway management is necessary in the prehospital environment and difficult airways occur more commonly in this setting. Failed intubation is closely associated with the most devastating complications of airway management. In an attempt to improve the safety and success of tracheal intubation, we implemented videolaryngoscopy (VL) as our first-line device for tracheal intubation within a UK prehospital emergency medicine (PHEM) setting.MethodsAn East of England physician–paramedic PHEM team adopted VL as first line for undertaking all prehospital advanced airway management. The study period was 2016–2020. Statistical process control charts were used to assess whether use of VL altered first-pass intubation success, frequency of intubation-related hypoxia and laryngeal inlet views. A survey was used to collect the team’s views of VL introduction.Results919 patients underwent advanced airway management during the study period. The introduction of VL did not improve first-pass intubation success, view of laryngeal inlet or intubation-associated hypoxia. VL improved situational awareness and opportunities for training but performed poorly in some environments.ConclusionDespite the lack of objective improvement in care, subjective improvements meant that overall PHEM clinicians wanted to retain VL within their practice.