bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐reported exercise‐induced dyspnea and airways obstruction assessed by oscillometry and spirometry in adolescents
Authors: Veneroni Chiara , Pompilio Pasquale Pio , Alving Kjell , Janson Christer , Nordang Leif , Dellacà Raffaele , Johansson Henrik , Malinovschi Andrei 
Published: November 2021

AbstractBackgroundSelf‐reported exercise‐induced dyspnea (EID) is common among adolescents. Possible underlying pathologies are exercise‐induced bronchoconstriction (EIB) and laryngeal obstruction (EILO). The forced oscillation technique (FOT) may evaluate exercise‐induced changes in airway caliber.AimTo investigate in adolescents the relationship between EID, EIB (post‐exercise fall in forced expiratory volume in 1s (FEV1)≥10%), EILO, and post‐exercise challenge changes in FOT parameters.MethodsOne hundred and forty‐three subjects (97 with EID) of 13–15 years old underwent a standardized exercise challenge with FOT measurement and spirometry repeatedly performed between 2 and 30 min post‐exercise. EILO was studied in a subset of 123 adolescents. Subjects showing greater changes than the healthy subgroup in the modulus of the inspiratory impedance were considered FOT responders.ResultsEID‐nonEIB subjects presented similar post‐exercise changes in all FOT parameters to nonEID‐nonEIB adolescents. Changes in all FOT parameters correlated with FEV1 fall. 45 of 97 EID subjects responded neither by FEV1 nor FOT to exercise. 19 and 18 subjects responded only by FEV1 (onlyFEV1responders) or FOT (onlyFOTresponders), respectively. Only a lower baseline forced vital capacity (FVC)%predicted and a higher FEV1/FVC distinguished the onlyFEV1responders from onlyFOTresponders. FOT parameters did not present specific post‐exercise patterns in EILO subjects.ConclusionFOT can be used to identify post‐exercise changes in lower airway function. However, EID has a modest relation with both FEV1 and FOT responses, highlighting the need for objective testing. More research is needed to understand whether onlyFEV1responders and onlyFOTresponders represent different endotypes.
Immune and stromal related genes in colon cancer: Analysis of tumour microenvironment based on the cancer genome atlas (TCGA) and gene expression omnibus (GEO) databases
Authors: Wu Yue , Jia Haowei , Zhou Hangyuan , Liu Xinyu , Sun Junfeng , Zhou Xiaoyan , Zhao Hongchao 
Published: November 2021

AbstractThe incidence of colon cancer is amongst the top three in the world. The tumour microenvironment plays an important role in the occurrence and development of colon cancer. Stromal cells and immune cells are the main components of the tumour microenvironment. Our study detected genes, which affected the infiltration of stromal, immune cells and the way they affected the prognosis of colon cancer patients. We found that the colon's immune system had a special way to affect the tumour microenvironment. Moderate infiltration of stromal and immune cells was proved to be important protective factors for colon cancer patients, which has not been found in other tumours. C3, C5, CXCL12, GNAI1, LPAR1, PENK, PYY, SAA1 and SST were the differential expression hub genes of moderate‐stromal and immune score group. They had a more significant correlation with tumour purity and infiltration of B cells, CD8+ T cells, CD4+ T cells, macrophage, neutrophil, democratic cells. The proteins encoded by C3, C5, CXCL12, GNAI1, PENK, PYY, SST were detected in colon cancer cells. These genes had the potential to become markers to predict the prognosis of patients with colon cancer.
Gut tissue‐resident memory T cells in coeliac disease
Authors: Sollid Ludvig M. 
Published: November 2021

AbstractThis mini‐review describes observations of the 1990ies with culturing of gluten‐specific and astrovirus‐specific CD4+ T cells from duodenal biopsies from subjects who presumably had a long time between the exposure to gluten or astrovirus antigens and the sampling of the biopsy. In these studies, it was also observed that antigen‐specific CD4+ T cells migrated out of the gut biopsies during overnight culture. The findings are suggestive of memory T cells in tissue which are resident, but which also can be mobilised on antigen stimulation. Of note, these findings were made years before the term tissue‐resident memory T cells was invoked. Since that time, many observations have accumulated on these gut T cells, particularly the gluten‐specific T cells, and we have insight into the turnover of CD4+ T cells in the gut lamina propria. These data make it evident that human antigen‐specific CD4+ T cells that can be cultured from gut biopsies indeed are bone fide tissue‐resident memory T cells.
Interest rate rules and inflation risks in a macro‐finance model
Authors: Horvath Roman , Kaszab Lorant , Marsal Ales 
Published: November 2021

AbstractLong‐term bond yields contain a risk premium, an important part of which is compensation for inflation risks. The substantial increase in the Fed funds rate in the mid‐2000s did not raise long‐term US Treasury yields due to the reduction in the term premium (so‐called Greenspan conundrum) which was typically thought to be exogenous for monetary policy. We show using a New Keynesian macro‐finance model that the term premium is endogenous and is greatly influenced by the specification of the Taylor rule. Finally, we estimate our model using various specifications of Taylor rule on US data in 1961–2007 by the generalized methods of moments and evaluate the performance of our model.
Impersonals, passives, and impersonal pronouns: Lessons from Lithuanian
Authors: Šereikaitė Milena 
Published: November 2021

AbstractThis study examines the properties of VoiceP and impersonal pronouns by contrasting two constructions in Lithuanian: the‐ma/‐taimpersonal and the canonical passive. I argue that, while these two constructions overlap morphologically, they are syntactically distinct. The‐ma/‐taimpersonal is related to the‐no/‐toconstruction in Polish and in Ukrainian. Although it patterns with the Ukrainian‐no/‐topassive in allowing an auxiliary, it behaves like an active VoiceP with a null projected initiator in a thematic‐subject position, a pattern found in the Polish‐no/‐toimpersonal and other impersonals crosslinguistically. I show that the Lithuanian passive lacks a syntactically realized initiator and selects for a type of Voice without a specifier. I also analyze the properties of the impersonal pronoun of the‐ma/‐taimpersonal, demonstrating that it is a bare N that lacks inherently specified ɸ features (number, gender, and person) and has no case. This finding supports existing proposals that treat impersonal pronouns in different languages as defective.
Stomatal responses in grapevine become increasingly more tolerant to low water potentials throughout the growing season
Authors: Herrera Jose Carlos , Calderan Alberto , Gambetta Gregory A. , Peterlunger Enrico , Forneck Astrid , Sivilotti Paolo , Cochard Herve , Hochberg Uri 
Published: November 2021

SUMMARYThe leaf of a deciduous species completes its life cycle in a few months. During leaf maturation, osmolyte accumulation leads to a significant reduction of the turgor loss point (ΨTLP), a known marker for stomatal closure. Here we exposed two grapevine cultivars to drought at three different times during the growing season to explore if the seasonal decrease in leaf ΨTLP influences the stomatal response to drought. The results showed a significant seasonal shift in the response of stomatal conductance to stem water potential (gs~Ψstem), demonstrating that grapevines become increasingly tolerant to low Ψstem as the season progresses in coordination with the decrease in ΨTLP. We also used the SurEau hydraulic model to demonstrate a direct link between osmotic adjustment and the plasticity of gs~Ψstem. To understand the possible advantages of gs~Ψstem plasticity, we incorporated a seasonally dynamic leaf osmotic potential into the model that simulated stomatal conductance under several water availabilities and climatic scenarios. The model demonstrated that a seasonally dynamic stomatal closure threshold results in trade‐offs: it reduces the time to turgor loss under sustained long‐term drought, but increases overall gas exchange particularly under seasonal shifts in temperature and stochastic water availability. A projected hotter future is expected to lower the increase in gas exchange that plants gain from the seasonal shift in gs~Ψstem. These findings show that accounting for dynamic stomatal regulation is critical for understanding drought tolerance.
Evaluation of lymphocyte‐specific programmed cell death protein 1 receptor expression and cytokines in blood and urine in canine urothelial carcinoma patients
Authors: Pinard Christopher J. , Stegelmeier Ashley A. , Bridle Byram W. , Mutsaers Anthony J. , Wood R. Darren , Wood Geoffrey A. , Woods J. Paul , Hocker Samuel E. 
Published: November 2021

AbstractUrothelial carcinoma (UC) is the most common urinary tumour in dogs. Despite a range of treatment options, prognosis remains poor in dogs. In people, breakthroughs with checkpoint inhibitors have established new standards of care for muscle‐invasive bladder cancer patients and elevated levels of programmed cell death protein 1 (PD‐1) suggest immune checkpoint blockade may be a novel target for therapy. The goal of this study was to determine if canine UC patients express elevated levels of lymphocyte‐specific PD‐1 and/or urinary cytokine biomarkers compared to healthy dogs. Paired blood and urine were evaluated in 10 canine UC patients, five cystitis patients and 10 control dogs for lymphocyte‐specific PD‐1 expression via flow cytometry and relative cytokine expression. In UC patients, PD‐1 expression was significantly elevated on CD8+ lymphocytes in urine samples. UC patients had a higher CD4:CD8 ratio in their urine compared to healthy dogs, however, there was no significant variation in the CD8:Treg ratio between any group. Cystitis patients had significantly elevated levels of CD4+ T cells, CD8+ T cells and Tregs in their blood samples compared to UC patients and healthy dogs. Cytokine analysis demonstrated significant elevations in urinary cytokines (granulocyte‐macrophage colony‐stimulating factor, interferon‐gamma [IFN‐γ], interleukin (IL)‐2, IL‐6 IL‐7, IL‐8 and IL‐15, IP‐10, KC‐like, IL‐18, monocyte chemoattractant protein‐1 and tumour necrosis factor‐alpha). Several of these cytokines have been previously correlated with both lymphocyte‐specific PD‐1 expression (IFN‐γ, IL‐2, IL‐7 and IL‐15) in muscle‐invasive urothelial carcinoma in humans. Our results provide evidence of urinary lymphocyte PD‐1 expression and future studies could elucidate whether veterinary UC patients will respond favourably to anti‐PD‐1 immune checkpoint inhibitor therapy.
Analysis on Combined Heat and Power and Combined Heat and Power Hybrid Systems for Unconventional Drilling Operations
Authors: Dranuta Diego , Johnson Derek 
Published: November 2021

Abstract
The United States (U.S.) has experienced a natural gas “boom” due to the development of unconventional shale plays, but well development is energy intensive. Operations use electric drilling rigs typically powered by either three high-horsepower diesel engines (HHPDE) or three dedicated natural gas engines (DNGE) and associated generators. From a first law analysis, HHPDEs peak at about 42% efficient at full load, while DNGE peak at about 30%. Most fuel energy is lost as heat rejected by the exhaust and radiators. Concurrently, during cold seasonsor or in cold regions rigs utilize boilers to provide steam throughout the rig to prevent freezing and provide comfort.
Our analysis focused on a combined heat power (CHP) approach to improve the utilization factor (UF) of fossil energy consumed during unconventional drilling operations. Engine activity, boiler fuel consumption, and exhaust gas temperatures were recorded during winter drilling of an entire well in the Marcellus shale. Four characteristic activity cycles were extracted from recorded activity to represent four energy consumption scenarios. Exhaust and jacket water heat exchangers (E-HEX, JW-HEX) were designed and simulated, and results were analyzed in 0-D models for the four case scenarios. A 584-kWh hybrid energy management system (HEMS) was also designed and simulated into the model as another method to reduce fossil energy fuel consumption during well development.
HHPDE UF improved on average from 35.7% to 55.7% if only E-HEX were used and improved to 72.7% if JW-HEX were also used. DNGE average UF increased from 19.0% to 34.9% using E-HEX only. HEMS utilization improved UF up to an average of 76.9% and 39.1% for HHPDE CHP and DNGE CHP systems, respectively.
Analysis of Premixed Laminar Combustion of Methane With Noble Gases as a Working Fluid
Authors: Baghirzade Mammadbaghir , Nasim Md Nayer , Nawaz Behlol , Aguilar Jonathan , Shahsavan Martia , Morovatiyan Mohammadrasool , Mack John Hunter 
Published: November 2021

Abstract
Hydrodynamic and diffusional-thermal instabilities affect the flame dynamics, which result in non-planar flame fronts with self-accelerating cellularities and wrinkles. In premixed flames, the driving mechanism for perturbations is hydrodynamic instabilities, which are associated with thermal expansion. Under high-pressure conditions, such as in spark-ignition engines, the flame curvature and morphology might be influenced by the hydrodynamic instabilities. This study focuses on the replacement of nitrogen with a noble gas (argon and krypton) as the working fluid in the premixed combustion of methane to investigate its effect on flame stability and dynamics. The utilization of noble gases can also enhance the ideal thermal efficiency of internal combustion engines due to the higher specific heat ratio they possess and may also reduce the NOx emissions markedly because of the lack of nitrogen in the working fluid. The experiments are conducted for various equivalence ratios (φ = 0.8, 1.0, 1.2) in a constant volume combustion chamber (CVCC) at atmospheric and elevated initial pressures and atmospheric temperature. As an outcome of this study, to understand the influence of krypton on methane combustion, spherically propagating flames are analyzed in terms of the laminar flame burning velocity, cellular instability, unburned gas Markstein length, and flame morphology utilizing a Z-type Schlieren optical diagnostic technique and fractal analysis, which is a promising approach to analyze flame surfaces. The fractal dimension of the flame fronts is calculated by a box-counting algorithm. The results are compared against the previously examined case studies in which argon was used as the primary working fluid.
High-Fidelity Energy Deposition Ignition Model Coupled With Flame Propagation Models at Engine-Like Flow Conditions
Authors: Kazmouz Samuel J. , Scarcelli Riccardo , Kim Joohan , Cheng Zhen , Liu Shuaishuai , Dai Meizhong , Pomraning Eric , Senecal Peter K. , Lee Seong-Young 
Published: November 2021

Abstract
With the heightened pressure on car manufacturers to increase the efficiency and reduce the carbon emissions of their fleets, more challenging engine operation has become a viable option. Highly dilute, boosted, and stratified charge, among others, promise engine efficiency gains and emissions reductions. At such demanding engine conditions, the spark-ignition process is a key factor for the flame initiation propagation and the combustion event. From a computational standpoint, there exists multiple spark-ignition models that perform well under conventional conditions but are not truly predictive under strenuous engine operation modes, where the underlying physics needs to be expanded. In this paper, a hybrid Lagrangian-Eulerian spark-ignition (LESI) model is coupled with different turbulence models, grid sizes, and combustion models. The ignition model, previously developed, relies on coupling Eulerian energy deposition with a Lagrangian particle evolution of the spark channel, at every time-step. The spark channel is attached to the electrodes and allowed to elongate at a speed derived from the flow velocity. The LESI model is used to simulate spark ignition in a non-quiescent crossflow environment at engine-like conditions, using CONVERGE commercial CFD solver. The results highlight the consistency, robustness, and versatility of the model in a range of engine-like setups, from typical with RANS and a larger grid size to high fidelity with LES and a finer grid size. The flame kernel growth is then evaluated against schlieren images from an optical constant volume ignition chamber with a focus on the performance of flame propagation models, such as G-equation and thickened flame model, versus the baseline well-stirred reactor model. Finally, future development details are discussed.
On-Engine Expansion Measurement of Exhaust Manifold for Calibrating Thermo-Mechanical Fatigue FEA Model
Authors: Kulkarni Girish J. , Kakde Pravin , Parekar Vinod , Mestry Kapil , Bhosle Sandeep 
Published: November 2021

Abstract
An attempt was made as part of this work to acquire on-engine measurements to identify how closely current Finite Element Analysis (FEA) models replicate actual on-engine exhaust manifold behavior. Further correlation study with FEA models was performed to understand and eliminate the gaps to improve the overall FEA process.
Dry cast iron exhaust manifolds experience thermo-mechanical fatigue (TMF) during engine operation. This is one of the critical failure modes. Literature is available to perform TMF assessment of exhaust manifold e.g. [1–6]. However, it is difficult to accurately predict TMF life of exhaust manifold in FEA due to dependency on multiple factors such as non-linear material behavior [3], temperature dependent material behavior, oxidation effect, creep effect, accuracy in prediction of metal temperatures and joint friction effects. Typically, non-linear material models, creep effects and oxidation effects are accounted by advanced fatigue processing software. Non-linear material models account for material and for temperature dependent non-linearity [4]. These non-linear material model and fatigue parameters are often developed using uniaxial specimen level testing. These doesn’t account for all the complexity during on-engine test due to factors such as friction and bolt loads that can influence manifold behavior. FEA processes for exhaust manifolds are seldom calibrated with on-engine measurements due to the complexity of obtaining these measurements in an environment that has severe temperatures and vibrations.
The correlation study highlighted that exhaust manifold was over constrained by excessive clamping in FEA. This raised question on the gasket coefficient of friction (COF) and working preloads. These settings were investigated to get better correlation.
Using reduced COF and non-linear material model for manifold capscrews, helped to achieve better correlation. Replacing material properties of manifold capscrews with nonlinear data provided capability to simulate localized yielding of capscrews and hence the corresponding load loss. Using these new settings for few other case studies also showed improvement in correlation of manifold warpage and thermal fatigue life prediction. Outcome of this work was a refined FEA approach which showed better FEA to Test correlation for exhaust manifold subject to thermal loading.
Investigating the Origins of Cyclic Variability in Internal Combustion Engines Using Wall-Resolved Large Eddy Simulations
Authors: Wu Sicong , Patel Saumil S. , Ameen Muhsin M. 
Published: November 2021

Abstract
Modern internal combustion engines (ICE) operate at the ragged edge of stable operation characterized by high cycle-to-cycle variations (CCV). A key scientific challenge for ICE is the understanding, modeling, and control of CCV in engine performance, which can contribute to partial burns, misfire, and knock. The objective of the current study is to use high-fidelity numerical simulations to improve the understanding of the causes of CCV. Nek5000, a leading high-order spectral element, open source code, is used to simulate the turbulent flow in the engine combustion chamber. Multi-cycle, wall-resolved large-eddy simulations (LES) are performed for the General Motors (GM), Transparent Combustion Chamber (TCC-III) optical engine under motored operating conditions. The mean and root-mean-square (r.m.s.) of the in-cylinder flow fields at various piston positions are validated using PIV measurements during the intake and compression strokes. The large-scale flow structures, including the swirl and tumble flow patterns, are analyzed in detail and the causes for cyclic variabilities in these flow features are explained. The energy distribution across the different scales of the flow are quantified using one-dimensional energy spectra, and the effect of the tumble breakdown process on the energy distribution is examined. The insights from the current study can help us develop improved engine designs with reduced cyclic variabilities in the in-cylinder flow leading to enhanced engine performance.
Optimization of a Marine Medium-Speed Engine With Multi-Injector System by 1D Predictive Simulation
Authors: Liu Dai , Zhang Peng , Liu Long , Xia Qian , Ma Xiuzhen 
Published: November 2021

Abstract
The thermal efficiency and emission of large bore marine medium-speed diesel engine are required to be improved under the stringent legislations. A multi-injector system has been proposed in order to improve the thermal efficiency and NOx emission instantaneously. However, application of the multi-injector system increased the complexity of parameter optimization and control. To develop proper control strategy of the novel multi-injector system, a 1D engine model of the original engine configurations was developed initially, including a predictive combustion model in commercial 1D simulation program (GT-Power). After calibrated by test results and literature data under various engine loads, the engine model was modified from a central single injector engine to a multi-injector engine. On the basis of a conventional direct-injection diesel engine, another two injectors were added to the cylinder as side injectors in the model. And the fundamental combustion characteristics and engine performance of the marine medium-speed diesel engine with multi-injector are investigated under various injection quantity ratio between the central injector and side injectors. The effects of injection timing and split injection are also studied by simulation. The result indicated that the effective thermal efficiency and NOx emission of the medium speed marine diesel engine are optimized instantaneously by changing the injection strategies of the central and side injectors. Finally, the preferred injection strategy is proposed by the 1D model.