bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Investigation of the Effect of Air-Handling and DME-Propane Blends on the Performance and Emissions of a 4-Cylinder CI Engine
Authors: Hassan Hafiz Ahmad , Ankobea-Ansah King , De Ojeda William , Wu Simon Haibao , Hall Carrie 
Published: December 2024

Abstract
Dimethyl ether (DME) is considered an excellent alternative to diesel because of its higher cetane number and lower carbon content. Additionally, DME can be blended with abundantly available propane with minimal modifications to the propane infrastructure. This paper focuses on an experimental investigation of the effect of air-handling i.e., boost pressure and exhaust gas recirculation (EGR), and DME-propane blends on the combustion and emissions performance of a light-duty, four-cylinder, compression ignition (CI) engine. The boost pressure and EGR sweeps were carried out and showed that higher boost pressures resulted in increased brake thermal efficiencies (BTE) at the expense of higher NOx emissions which could be reduced by an increase in EGR. The fuel sweeps were carried out at 0, 15 and 25% propane (neat, 85% and 75% DME) with 0% and 25% EGR. The fuel sweeps indicated that the ignition delay (ID) increased and burn duration (BD) decreased monotonically when the blend increased to 25% propane/75% DME. The results suggest optimum engine performance with neat DME at 105 kPa boost pressure and 25% EGR with propane addition improving the BTE with negligible increase in emissions. Higher contents of Propane, up to 25%, did not affect the variability of combustion, with standard deviations of burn duration and peak cylinder pressures below 1% for all test cases.
Computational Model Validation of a Non-Firing Compression Ignition Engine and Chemical Kinetic Mechanism Selection for Diesel-Pilot Assisted Methane Combustion
Authors: Shaalan Amr , Sirna Amanda , Loprete Jason , Mathai Joel Reji , Trelles Juan Pablo , Mack J. Hunter , Van Dam Noah , Lopez-Pintor Dario , Assanis Dimitris 
Published: December 2024

Abstract
In this study, a computational fluid dynamics (CFD) model of a single-cylinder compression ignition engine is developed and validated under motoring conditions. The engine used is the Ricardo Hydra engine at the Advanced Combustion and Energy Systems laboratory at Stony Brook University, which is highly instrumented to collect all data necessary for experimental validation of high-fidelity 3-D model simulation. The model is validated against experimental data for various intake pressures and temperatures. The results show that the model can predict the in-cylinder pressure trace with a peak-pressure accuracy ranging from 0.8% to 1.9% while the trapped mass accuracy ranges from 0.9% to 2.3% depending on the operating conditions. A skeletal chemical kinetic mechanism for diesel fuel is also presented. The mechanism is validated against experimental data for ignition delay, NOx formation, and PAH formation. The results show that the mechanism can accurately predict the combustion behavior of diesel fuel. The validated CFD model and chemical kinetic mechanism will be used in future studies to investigate the potential of diesel-piloted methane as a low-carbon fuel.
Demonstration of Scaled Flowrate Testbed for Emission Aftertreatment Device Testing Under Representative Engine Exhaust Conditions
Authors: Loprete Jason , Kamal Nabil , Sirna Amanda , Mon Tala , Kyriakidou Eleni , Assanis Dimitris 
Published: December 2024

Abstract
The continued development of aftertreatment devices has been critical in reducing engine tailpipe emissions and meeting ever-evolving regulatory standards. Initial phases of catalytic aftertreatment device evaluation often occur at physically scaled-down conditions, typically using laboratory benchtop reactors to test synthesized catalysts that are coated on mini-cores with flow rates of less than 10 SLPM evaluated and often in the range of 0.1–1 SLPM. These flows are often generated artificially using bottled gases and heaters, which do not reflect the conditions that occur under real engine operation. This reduced-scale approach is driven by cost and time constraints, as full-scale device testing requires more catalyst material and production time. Real multicylinder engines produce exhaust flows several orders of magnitude greater than what occurs on the benchtop, with numbers ranging from 1000 to &gt; 10,000 SLPM in typical on-road automotive applications. An intermediary scale approach that can bridge this flowrate chasm is necessary for the efficient rapid prototyping of novel catalytic reactions for aftertreatment applications. This manuscript focuses on validating a variably scaled testbed for catalyst testing that aims to eliminate barriers between cost-effective small-scale testing and realistic full-scale implementations. This study builds on a previous work incorporating a slip-stream approach driven by a venturi-ejector to route flow through a secondary branch containing the catalyst. The current investigation specifically focuses on improving the system’s overall flexibility in terms of accommodating new aftertreatment devices and operating conditions, as well as reducing required auxiliary instrumentation. Differences between the previous iteration of the system are detailed and discussed, as well as recommendations for further improvements to the system. Engine operating parameters such as intake pressure, equivalence ratio, spark timing, compression ratio, and ejector motive pressure are utilized to create the required catalyst inlet temperature, flows, and species concentration for evaluation. The system is tested using a blank catalyst for verifying composition across sampling locations, as well as to generate an operational emissions space for determining the system’s ability to be utilized for intermediate-scale catalyst testing. Initial results show the system’s repeatability and lack of species conversion with an inert monolith to be sufficient for eventually deploying a production catalyst and determining conversion efficiency.
Influence of Engine Operating Parameters and Different Fuels on the Soot Reactivity of Diesel Engines
Authors: Böhmeke Christian , Wagner Uwe , Koch Thomas 
Published: December 2024

Abstract
Strong efforts to reduce CO2 emissions, including in commercial vehicle diesel engines, require the optimization of all processes and engine components that influence fuel consumption. Subsequently, also the additional fuel consumption for particulate regeneration is increasingly focused on. Increasing soot loading of the DPF increases the exhaust back pressure and is therefore deteriorating thermal engine efficiency. Additionally, DPFs are only providing specific maximum soot loading capacities and have to be regenerated accordingly by oxidizing the accumulated soot. The energy or temperature, respectively, which is required for oxidizing the soot to CO2 strongly depends on the physicochemical properties of the soot and is commonly described as particulate reactivity. More reactive soot is advantageous for fuel-efficient regeneration as it can be oxidized at lower temperatures.
This work deals with the influence of various engine operating parameters (speed, load, air-fuel ratio, EGR, injection) as well as the influence of fuels on particulate emissions. The associated soot reactivity is compared between conventional fossil diesel (with and without fatty acid methyl ester), regeneratively produced paraffinic diesel fuel HVO (Hydrotreated vegetable oil) and a blend of HVO and oxymethylene ether (OME). All investigations were performed on a single-cylinder research engine. The engine out particle measurements were carried out using a particle size spectrometer and a photoacoustic sensor. Gaseous emissions were recorded using an exhaust gas measuring system and an infrared spectrometer. Additionally, collected engine out soot samples a thermogravimetric analysis (TGA) was implemented to determine the reactivity of the soot.
Regardless of the engine operating point set, it was found that the particulate mass for the HVO fuel is significantly lower than the particulate mass of the fossil diesel fuels. In contrast, however, the HVO fuel has an increased number of particles due to smaller particles. A significantly lower particle mass and particle number concentration was achieved with the HVO/OME blend. The NOx emissions were at a similar level regardless of the fuel used. A variation of engine operating parameters showed the same tendencies in terms of soot reactivity, regardless of the fuel used. However, the parameter variations were more or less pronounced depending on the respective fuel. It is particularly noteworthy that, aside from operation at low EGR rates and high air-fuel-ratios, where higher reactivities were observed when using diesel B0, no significant differences in reactivity were evident among the fuels used.
Effects of Inlet Port Geometry on MCC Mixing Sensitivity Study
Authors: Beurlot Kyle , Jacobs Timothy 
Published: December 2024

Abstract
Pre-combustion chambers are a common pathway to improve ignition stability and combustion quality while simultaneously offering significant emissions reduction potential in large-bore natural gas two-stroke engines. Prechambers serve to help reduce the carbon footprint of these pipeline engines by extending the lean ignition limits of operation, reducing fuel consumption and overall greenhouse gas emissions. By extension, the significant reduction potential of overall emissions from legacy engines serves to reduce the carbon footprint of pipeline compressor stations across the nation. Based on the foundations of previous research with encouraging results in prechambered engines, this study utilized a numerical simulation approach to evaluate new concepts for improving mixture homogeneity during the scavenging and gas exchange process in an industry relevant large bore natural gas two stroke engine. The simulation was created using Converge CFD software and was validated using experimental data. A wide variety of concepts were tested, and various parameters, including overall air flow, mixture quality, and flow field interaction are evaluated for their influences on the combustion process, including residual methane and NO production mechanisms. The paper reviews and analyzes the sensitivity of the prechamber and main chamber interactions to these parameters, providing fundamental insight into the combustion process and emissions formation.
Combustion Characteristics of Hydrogen, Propane and Methane Gases in a Boosted Featureless Port-Injection SI Engine
Authors: Fakeye Adebayo , Yang Junfeng 
Published: December 2024

Abstract
The search for alternative transport fuel with comparable performance to fossil fuels in powering internal combustion engines (ICEs) has been a topical research project for decades. This is important because ICE is a well-developed technology, but fossil fuels are a finite resource, yet their consumption causes environmental damage. The alternative fuel is therefore expected to overcome these limitations. Hydrogen gas has been on top of the list as the most suitable option, but it is widely proposed dilute it with other fuels for better performance. To understand the effects of diluents such as methane and propane on the combustion characteristics hydrogen gas, Particle Image Velocimetry (PIV) was employed in this study to compare the fundamental combustion characteristics of hydrogen, propane and methane as single fuels at similar conditions in a featureless Leeds University Ported Optical Engine, (LUPOE-2D). The experiments were carried out at low speed of 50 rpm and a boosted inlet pressure of 1.67 bar at port inlet closing, typical of a downsized engine. The mixtures were ignited during the compression stroke at 5 bar. The inlet air was heated, and the temperature of the cylinder head was slightly adjusted from room temperature of 25 ± 2°C for the different mixtures such that a temperature of 439K was obtained for the mixtures at spark pressure of 5 bar. The temperature was estimated using the first law of thermodynamics. Flame combustion characteristics such as flame wrinkling parameters, stretch rate, burning velocities, etc., were derived and compared. There is good agreement between the stretched laminar burning velocities derived from direct measurement of the flame speed and unburned gas velocities ahead of the flame front, extrapolated to the zero-stretch, the values derived from the products of the unstretched flame speeds and the density ratios, and Chemkin-computed values. The burning rates increased with increase in flame stretch except for H2 ϕ = 0.5 which increased to a peak before declining in similar manner as the flame stretch reached a peak and declined before the influence of wall confinement. The flame sphericity and the flame wrinkling amplitude were used to compare their flame wrinkling characteristics of the flames. H2 ϕ = 0.5 flames showed significant instability from the onset and became more winkled as the flame radius increased.
May Measurement Month 2022: results from the global blood pressure screening campaign
Authors: Beaney Thomas , Kerr Gabriele Keziah , Kiru Gaia , McArdle Harsha , Schlaich Markus , Schutte Aletta E , Stergiou George S , Wang Ji-guang , Marin Marcos J , Henandez-Hernandez Rafael , Diaz Alejandro Bimbo F , Alcocer Luis , Lopez-Jaramillo Patricio , Poulter Neil 
Published: December 2024

IntroductionElevated blood pressure (BP) is the major contributor to mortality and disease burden worldwide. May Measurement Month (MMM) is a global BP screening campaign, which aims to raise awareness of BP measurement and provide evidence to inform and influence related health policy.MethodsThis cross-sectional survey included individuals aged≥18 years recruited through opportunistic sampling at sites in 60 countries during MMM 2022. Each participant had three sitting BP measurements and a questionnaire was completed including demographics, comorbidities and lifestyle factors. Hypertension was defined as a systolic BP≥140 mm Hg and/or a diastolic BP≥90 mm Hg (average of the second and third readings) or taking antihypertensive medication. Multiple imputation was used to estimate BP readings where any participant’s BP readings were missing. Linear mixed effects models were used to identify associations between participant characteristics and systolic or diastolic BP.ResultsOf the 715 518 participants surveyed (excluding 50 200 self-measured home BP screenees recruited via the ZOE Health Study app), 257 421 (36.0%) were identified as hypertensive, of whom 57.6% were aware and 49.3% were on antihypertensive medication. Of all participants with hypertension, 26.1% were controlled to <140/90 mm Hg and 12.0% to <130/80 mm Hg. Of those taking antihypertensive medication, 52.7% were taking only one drug class, 52.9% were controlled to <140/90 mm Hg and 24.4% to 130/80 mm Hg. In total, 190 314 (26.6% of total surveyed, 73.9% of hypertensives) participants screened were found to have untreated or inadequately treated hypertension. Only 27.6% of treated hypertensive participants were taking a statin. Substantial coexistence of diabetes, overweight and hypertension was apparent among participants.ConclusionsMMM confirms a high global burden of hypertension with low rates of awareness, treatment and control. In the absence of systematic BP screening in many countries, the results from MMM underscore the continued need for BP screening to detect and thereby control raised BP.
Can oral cancer screening reduce late-stage diagnosis, treatment delay and mortality? A population-based study in Taiwan
Authors: Tsai Ethan , Walker Brigham , Wu Shiao-Chi 
Published: December 2024

ObjectiveThis study evaluates the effectiveness of Taiwan’s nationwide oral cancer screening programme in reducing late-stage diagnosis, treatment delays and mortality.DesignA retrospective cohort study was conducted.SettingThe study utilized Nationally representative datasets, including the Cancer Registry, Oral Mucosal Screening and National Health Insurance databases in Taiwan.ParticipantsThe study included patients with oral cancer diagnosed between 1 January 2010 and 31 December 2013, with follow-up through 31 December 2018. The final analysis included 16 430 patients.InterventionThe intervention was Taiwan’s nationwide oral cancer screening programme which provides visual inspection and palpation of the oral mucosa.Primary outcome measuresThe primary outcomes measured were late-stage diagnosis (stages III and IV), treatment delay (time from diagnosis to treatment >30 days) and all-cause mortality.ResultsOral cancer screening was statistically significantly associated with a reduced likelihood of late-stage diagnosis (adjusted OR (AOR)=0.85, 95% CI 0.80 to 0.91, p<0.01). However, screening was also associated with a higher likelihood of treatment delay (AOR=1.09, 95% CI 1.00 to 1.19, p=0.049). Taken together, the screening programme is associated with a slightly lower hazard of death (adjusted HR=0.94, 95% CI 0.89 to 0.99, p=0.01).ConclusionWhile Taiwan’s nationwide oral cancer screening programme effectively reduced late-stage diagnoses and mortality, barriers to timely treatment access remain. Ensuring prompt diagnosis and treatment following screening may further enhance the survival benefits of the programme.
State-of-the-art performance of deep learning methods for pre-operative radiologic staging of colorectal cancer lymph node metastasis: a scoping review
Authors: Keel Benjamin , Quyn Aaron , Jayne David , Relton Samuel David 
Published: December 2024

ObjectivesTo assess the current state-of-the-art in deep learning methods applied to pre-operative radiologic staging of colorectal cancer lymph node metastasis. Specifically, by evaluating the data, methodology and validation of existing work, as well as the current use of explainable AI in this fast-moving domain.DesignScoping review.Data sourcesAcademic databases MEDLINE, Embase, Scopus, IEEE Xplore, Web of Science and Google Scholar were searched with a date range of 1 January 2018 to 1 February 2024.Eligibility criteriaIncludes any English language research articles or conference papers published since 2018 which have applied deep learning methods for feature extraction and classification of colorectal cancer lymph nodes on pre-operative radiologic imaging.Data extraction and synthesisKey results and characteristics for each included study were extracted using a shared template. A narrative synthesis was then conducted to qualitatively integrate and interpret these findings.ResultsThis scoping review covers 13 studies which met the inclusion criteria. The deep learning methods had an area under the curve score of 0.856 (0.796 to 0.916) for patient-level lymph node diagnosis and 0.904 (0.841 to 0.967) for individual lymph node assessment, given with a 95% confidence interval. Most studies have fundamental limitations including unrepresentative data, inadequate methodology, poor model validation and limited explainability techniques.ConclusionsDeep learning methods have demonstrated the potential for accurately diagnosing colorectal cancer lymph nodes using pre-operative radiologic imaging. However, several methodological and validation flaws such as selection bias and lack of external validation make it difficult to trust the results. This review has uncovered a research gap for robust, representative and explainable deep learning methods that are end-to-end from automatic lymph node detection to the diagnosis of lymph node metastasis.
Compensatory function change by segment-counting method in predicted postoperative pulmonary function at 1 year after surgery: systematic review and meta-analysis
Authors: Wang Teng-Wei , Zhang Qiang , Cai Zhihong , Xu Qinhong , Lin Jinrong , Yeh Huilong 
Published: December 2024

BackgroundThis systematic review aimed to assess the accuracy of the segment-counting method in predicting long-term pulmonary function recovery and investigate compensatory changes following different extents of lung resection.MethodsWe included studies that measured forced expiratory volume at 1 s (FEV1) between 6 and 18 months postoperatively, comparing it to the predicted postoperative FEV1 (ppoFEV1) using the segment-counting method. The extent of lung resection was correlated with the ratio of postoperative FEV1 to ppoFEV1. A comprehensive search was conducted in Embase, MEDLINE and Web of Science using terms related to ‘lung resection’ and ‘pulmonary function’. The final search was completed on 18 February 2022. Risk of bias was assessed using the Newcastle-Ottawa Scale.Results39 studies comprising 78 observation cohorts met the inclusion criteria. The analysis showed significant differences in pulmonary function in patients with ≥3 resected segments. Meta-regression indicated that the number of resected segments significantly impacted the postoperative FEV1/ppoFEV1 ratio, explaining 57% of the variance (R²=0. 57), with moderate heterogeneity (I²=61. 87%) across studies. Other variables, including patient age, body mass index, video-assisted thoracoscopic surgery use and tumour stage, did not show significant effects.DiscussionLimitations of the review included moderate heterogeneity between studies and potential selection bias related to the stage of cancer and lung volume reduction effects. The findings suggest that the extent of lung resection correlates with better-than-expected pulmonary function, potentially due to compensatory mechanisms.PROSPERO registration numberThis review was registered on PROSPERO (CRD42021293608).
Comparative retrospective study of injuries during military parachuting training and airborne operations from 2013 to 2020
Authors: Rebours Yannick , Aigle L , Agard G , Godron J , Michoud G 
Published: December 2024

IntroductionFrench paratroopers have been deployed during airborne operations for nearly a century. Parachute operations have increased since the start ofOperations ServalandBarkhanein the Sahelo-Saharan strip. These military operations allow paratroopers to be dropped behind enemy lines. Our primary objective was to compare injuries sustained during airborne operations and training. Our secondary objective was to compare serious injuries sustained during airborne operations and training.MethodsWe conducted a multicentric comparative retrospective study of military parachuting injuries sustained during training and airborne operations from 1 January 2013 to 31 December 2020. Parachuting injuries included in our study came from the French Army Injury Register.ResultsDuring the study period, 91 injuries (among 90 wounded), including one death, were recorded during airborne operations and 2744 injuries (among 2516 wounded), including one death, were recorded during training. Proportionally, injuries were more common during airborne operations (3.3%) than training (0.3%), especially during military freefall operations. Operational static-line jumps are more associated with serious injuries than training ones (OR 3.17, 95% CI 1.79 to 5.62). Compared with training, operational jumps caused proportionally more knee injuries (OR 2.73, 95% CI 1.65 to 4.51, p=0.008) but fewer upper limb injuries (OR 0.36, 95% CI 0.17 to 0.74). A physician and/or nurse medically supported 83.3% of airborne operations. Data collection initially differed between paratrooper units until the French Army introduced a harmonised collection tool (Register of Parachuting Incidents (Fiche de Recueil Accident en Parachute)).ConclusionOur study highlights a significantly increased injury rate during airborne operations, especially serious ones, likely due to the cumulative effect of well-known parachuting risk factors (eg, unknown or high wind speed, unknown landing ground type, combat load and night drop), justifying surveillance by qualified parachuting health staff.