bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myoglobin saturation as an intracellular indicator for transfusion need in oncology patients
Authors: Schenkman Kenneth A. , Ciesielski Wayne A. , Gernsheimer Terry B. , Arakaki Lorilee S. L. 
Published: August 2024

AbstractObjectivesThis study aims to demonstrate the potential of myoglobin saturation as an indicator of oxygen delivery adequacy to help determine the need for red cell transfusion.BackgroundModern blood management approaches have been established to optimise use of red blood cells for transfusions in patients with anaemia. However, most approaches make recommendations to transfuse based on haemoglobin or haematocrit levels and do not directly address adequacy of oxygen delivery. Intracellular oxygen determined by myoglobin saturation directly measures oxygen delivery at the tissue level.Methods/MaterialsA custom built spectrometer system with an optical fibre probe was used in this pilot study to measure muscle cell myoglobin saturation noninvasively from the first digital interosseous muscles in patients undergoing planned red blood cell transfusion. Patients were recruited from both the in‐patient and out‐patient oncology service at a major university medical centre. Measurements were made immediately before, immediately after, and 24 h following transfusion. Clinical data and tissue oxygen values from the Somanetics INVOS system were also collected.ResultsMyoglobin saturation, and thus cellular oxygen increased in some, but not all patients receiving a transfusion, and was most pronounced in patients who initially had low myoglobin saturation compared with the group as a whole.ConclusionClinical decisions to transfuse based on haemoglobin or haematocrit thresholds alone are likely insufficient to optimise use of red blood cell transfusions. The combination of haemoglobin or haematocrit with myoglobin saturation may optimally determine who will benefit physiologically from a transfusion.
Transfusion sample mislabelling and wrong blood in tube in the UK: Insights from the national comparative audits of blood transfusion in 2012 and 2022
Authors: Booth Catherine , Davies Paul 
Published: August 2024

AbstractBackgroundSamples for transfusion rejected due to mislabelling can lead to harm when a patient has to be re‐bled or has a transfusion or procedure delayed. Electronic labelling systems which scan the patient's identification band and generate a label at their side aim to reduce mislabelling and misidentification leading to wrong blood in tube (WBIT) errors. The 2022 National Comparative audit of sample collection aimed to compare national rates of sample mislabelling and WBIT to the 2012 audit and to examine the impact of electronic systems.MethodAll UK hospitals were invited to provide data on rejected transfusion samples and WBIT incidents in 1 month (October 2022) and were asked if they had electronic labelling.ResultsTwenty‐three thousand five hundred and eighty‐four rejected samples were reported by 179 sites in 1 month. The rejection rate of 4.4% represents a 47% increase compared to 2012 (2.99%). There were 92 WBIT incidents, an incidence of 1 in 5882 samples—a 45% increase compared to 1 in 8547 in 2012. Twenty‐three percent of sites can print a sample label at the patient's side, up by 224%. The six sites using only electronic sample labelling had a 46.9% lower rejection rate than sites using only hand‐labelling but still reported WBIT.ConclusionsThe increase in sample rejection and WBIT may reflect pressures facing clinical staff, zero tolerance policies and the two‐sample rule. A human factors approach to understanding and tackling underlying reasons locally is recommended. Electronic systems are associated with fewer labelling errors, but careful implementation and training is needed to maximise their safety benefits.
Stable twisted cohomology of the mapping class groups in the unit tangent bundle homology
Authors: Kawazumi Nariya , Soulié Arthur 
Published: August 2024

AbstractWe compute the stable cohomology groups of the mapping class groups of compact orientable surfaces with one boundary, with twisted coefficients given by the rational homology of the unit tangent bundles of the surfaces. These coefficients define a covariant functor over the classical category associated to mapping class groups, rather than a contravariant one, and are thus out of the scope of the traditional framework to study twisted cohomological stability. A remarkable property is that the computed stable twisted cohomology is not free as a module over the stable cohomology algebra with constant rational coefficients. For comparison, we also compute the stable cohomology group with coefficients in the first rational cohomology of the unit tangent bundle of the surface, which fits into the traditional framework.
Jun‐activated SOCS1 enhances ubiquitination and degradation of CCAAT/enhancer‐binding protein β to ameliorate cerebral ischaemia/reperfusion injury
Authors: He Chuan , Wang Tie , Han Yanwu , Zuo Changyang , Wang Guangming 
Published: August 2024

AbstractThis study investigates the molecular mechanisms behind ischaemia/reperfusion (I/R) injury in the brain, focusing on neuronal apoptosis. It scrutinizes the role of the Jun proto‐oncogene in apoptosis, involvement of SOCS1 in neural precursor cell accumulation in ischaemic regions, and the upregulation of C‐EBPβ in the hippocampus following I/R. Key to the study is understanding how Jun controls C‐EBPβ degradation via SOCS1, potentially offering new clinical treatment avenues for I/R. Techniques such as mRNA sequencing, KEGG enrichment analysis and protein–protein interaction (PPI) in mouse models have indicated involvement of Jun (AP‐1) in I/R‐induced cerebral damage. The study employs middle cerebral artery occlusion in different mouse models and oxygen–glucose deprivation/reoxygenation in cortical neurons to examine the impacts of Jun and SOCS1 manipulation on cerebral I/R injury and neuronal damage. The findings reveal that I/R reduces Jun expression in the brain, but its restoration lessens cerebral I/R injury and neuron death. Jun activates SOCS1 transcriptionally, leading to C‐EBPβ degradation, thereby diminishing cerebral I/R injury through the SOCS1/C‐EBPβ pathway. These insights provide a deeper understanding of post‐I/R cerebral injury mechanisms and suggest new therapeutic targets for cerebral I/R injury.
imageKey points
Jun and SOCS1 are poorly expressed, and C‐EBPβ is highly expressed in ischaemia/reperfusion mouse brain tissues.
Jun transcriptionally activates SOCS1.
SOCS1 promotes the ubiquitination‐dependent C‐EBPβ protein degradation.
Jun blunts oxygen–glucose deprivation/reoxygenation‐induced neuron apoptosis and alleviates neuronal injury.
This study provides a theoretical basis for the management of post‐I/R brain injury.
Topology Optimization Driven Bone-Remodeling Simulation for Lumbar Interbody Fusion
Authors: Wang Zuowei , Zhang Weisheng , Meng Yao , Xiao Zhe , Mei Yue 
Published: August 2024

Abstract
This study proposes a numerical approach for simulating bone remodeling in lumbar interbody fusion (LIF). It employs a topology optimization method to drive the remodeling process and uses a pixel function to describe the structural topology and bone density distribution. Unlike traditional approaches based on strain energy density or compliance, this study adopts von Mises stress to guide the remodeling of LIF. A novel pixel interpolation scheme associated with stress criteria is applied to the physical properties of the bone, directly addressing the stress shielding effect caused by the implanted cage, which significantly influences the bone remodeling outcome in LIF. Additionally, a boundary inverse approach is utilized to reconstruct a simplified analysis model. To reduce computational cost while maintaining high structural resolution and accuracy, the scaled boundary finite element method (SBFEM) is introduced. The proposed numerical approach successfully generates results that closely resemble human lumbar interbody fusion.
Experimental and Simulation Investigation of J-Shaped and Kammtail Virtual Airfoils in Small-Scale Horizontal Axis Wind Turbines
Authors: Al Hamad Saif , Abousabae Mohamed , Shaker Omar , Amano Ryoichi S. 
Published: August 2024

Abstract
In this work, the performance of new wind blade designs for small-scale horizontal axis wind turbines (HAWTs) was studied and compared with the performance of a baseline design. The studied designs were J-shaped and Kammtail Virtual Foil (KVF) profiles. Three J-shaped opening ratios (1/3, 1/2, and 2/3) and two KVF truncation ratios (1/8 and 1/4) were studied. All proposed designs were first investigated in a two-dimensional simulation study to get the lift-to-drag ratio by applying different wind speeds and angles of attack. The baseline design was experimentally investigated. Output power was measured using a digital rotary torque sensor using three different wind speeds. Tip speed ratio (TSR) was calculated after measuring each wind speed’s free rotating revolutions per minute (RPM). Three wind speeds and experimental TSRs were used in three-dimensional simulation to capture the performances of the proposed designs and compare them with the baseline. The simulation investigation was carried out for lab-scale and scaled designs. The two-dimensional study found that the J-shaped and KVF airfoils yielded more lift-to-drag ratios than the baseline for some angles of attack and wind speeds. The three-dimensional study found that the J-shaped blades enhanced the performance of the HAWTs for both lab-scale and scaled designs. J-shaped blades with a 1/3 opening ratio yielded an average power coefficient enhancement of around 1.56% and 4.16% for lab-scale and scaled designs, respectively. J-shaped blades with a 1/2 opening ratio yielded an average power coefficient enhancement of around 1.15% and 4.23% for lab-scale and scaled designs, respectively. On the other hand, J-shaped blades with a 2/3 opening ratio yielded an average power coefficient enhancement of around −0.12% and 2.54% for lab-scale and scaled designs, respectively. Furthermore, it was found that the KVF blades diminished the performance for both lab-scale and scaled designs.
Numerical Study on Effects of Different Corrugated Height and Initial Crossflow on Impingement Jet Heat Transfer
Authors: Hatta Masayoshi , Merritt-Webster Thomas , Rosic Budimir 
Published: August 2024

Abstract
More efficient gas turbines are required to realize a decarbonized society. To improve gas turbine performance, it is important to increase turbine inlet temperature and to decrease the mass flow rate of turbine cooling air. Impingement cooling is a well-known and effective heat transfer method, and it is commonly used to cool high temperature turbine components. One of the key problems found with impingement cooling is that crossflow created by upstream impingement negatively impacts the performance of downstream jets. Literature shows that corrugated style impingement geometries are a reliable and effective way to manage crossflow. However, the internal space of the airfoil is limited, limiting the maximum corrugated height. Therefore, it is important to establish the impact of corrugated height in crossflow mitigation, to understand the key flow mechanisms and to consider the effects in high crossflow scenarios found in larger impingement hole arrays.
In this study, the effect of corrugated height and initial crossflow on impingement jet heat transfer are numerically investigated. To quantify performance, pumping power and Nusselt number are compared between flat plate, low corrugated and high corrugated impingement geometries. A control volume methodology is implemented to evaluate the contributions of crossflow and impingement to overall loss. Vortical structures are visualised to analyse the key mechanisms by which crossflow interacts with succeeding impingement jets. Impingement jet diameter, jet to jet pitch and distance from impingement plate to target plate are kept the same for each geometry. Calculations are performed for Reynolds numbers of 10,000 and a SST k-ω turbulence model is used. The results of the study show that for the low crossflow condition, Nusselt number enhancement is 5–10% and increases up to 20% under the high crossflow condition, even at a small corrugated height. Improved cooling allows designers to decrease the mass flow rate of cooling air, enabling improved gas turbines efficiency.
Assessing the Effect of Coriolis Acceleration on the Coherent Structures in the Wake of a Wind Turbine Using DMD
Authors: Manganelli Felice , Bernardi Claudio , Leonardi Stefano , Cherubini Stefania , De Palma Pietro 
Published: August 2024

Abstract
The present work aims at studying the effect of veer, namely, the height-dependent lateral deflection of wind velocity due to Coriolis acceleration, on the coherent structures in the wake of the NREL 5-MW reference wind turbine using the sparsity-promoting dynamic mode decomposition (SP-DMD) method for the detection of dynamically-relevant flow structures. Large eddy simulation of the flow impacting the wind turbine is carried out by solving the filtered Navier-Stokes equations for incompressible flows. The effects of both tower and nacelle are included in the simulation using the immersed boundary method. Simulations are performed at Re ≈ 108, generating the inlet velocity profile by a precursor simulation of the atmospheric boundary layer subjected to Coriolis acceleration. The most relevant modes are extracted from the wake by the SP-DMD method and a limited subset of relevant flow features that optimally approximates the original data sequence is identified, which can be employed for developing an accurate reduced order model of the wake. The effects of the Coriolis acceleration on the dynamics of these modes are discussed in detail and the basic mechanisms by which the wind veer significantly affects the wake recovery rate are highlighted.
Large Eddy Simulation With Sliding Mesh Method of a Small-Scale Turbojet Engine
Authors: Briones Alejandro M. , Rankin Brent A. 
Published: August 2024

Abstract
A wall-adapting local-eddy (WALE) large eddy simulation (LES) with sliding mesh method (SMM) of a small-scale turbojet engine is conducted. A multi-table compressible flamelet/progress variable (FPV) approach is used for the combustion model. The freestream pressure and temperature, fuel flow rate, and shaft angular speed are the only inputs needed for the CFD simulations. The simulations are performed at static sea level and maximum power. The simulation is initiated using a steady Reynolds-average Navier-Stokes (RANS) simulation with multiple reference frame (MRF) and FPV methods. The mass flow rate from the RANS simulation is used as an input for the transient LES/SMM/FPV turbojet simulation. The LES results are consistent with RANS simulations, cycle analyses, and experimental data in terms of total temperature and pressure at the diffuser-combustor interface, air and fuel mass flow rate, equivalence ratio, and thrust. The spatial and temporal distributions of static temperature, static pressure, and axial and azimuthal velocity at the diffuser-combustor and combustor-turbine stator interfaces are examined and discussed in detail.
Thickened Flame Model Extension for Dual Gas GT Combustion: Validation Against Single Cup Atmospheric Test
Authors: Meloni Roberto , Babazzi Giulia , Giannini Nicola , Castellani Simone , Nassini Pier Carlo , Picchi Alessio , Galeotti Sofia , Becchi Riccardo , Andreini Antonio 
Published: August 2024

Abstract
The development of predictive combustion models is more and more strategic in the design definition of gas turbine combustor. The Thickened Flame Model (TFM), despite its high computational cost, is one of the most accurate approach available in literature since it can naturally take into account the non-equilibrium effects into the flame brush (i.e., strain and heat losses) as well as preferential diffusion when hydrogen is employed. Conversely, the original formulation of this combustion model needs several adjustments to accommodate the properties of the mixture when different streams of fuels and/or oxidizers are present in the system.
The present work represents a first step in the extension of this combustion model to handle multiple streams of fuels and oxidizers. More specifically, an industrial burner fed with two different fuel streams and air as oxidizer is considered. The pilot fuel line is fed with micro hydrogen injections with the aim to enhance the lean blow-out margin, while the main one with pure methane. Dedicated tests are performed at the THT laboratory (University of Florence) to retrieve the main information characterizing the burner (emissions, temperature and pressure pulsations) as well as OH* chemiluminescence for the flame shape and position at the same operating conditions.
The comparison between the numerical results and the experimental data will provide highlights about the ability of the extended-TFM to capture the main features of the flame stabilization mechanisms.
Impacts of Material and Machine on the Variation of Additively Manufactured Cooling Channels
Authors: Altland Abbigail Y. , Corbett Thomas M. , Thole Karen A. 
Published: August 2024

Abstract
While additive manufacturing (AM) can reduce component development time and create unique internal cooling designs, the AM process also introduces several sources of variability, such as the selection of machine, material, and print parameters. Because of these sources, wide variations in a part’s geometrical accuracy and surface roughness levels can occur, especially for small internal cooling features that are difficult to post-process. This study investigates how the selection of machine and material in the AM process influences variations in surface quality and deviations from design intent. Two micro-scale cooling geometries were tested: wavy channels and diamond-shaped pin fins. Test coupons were fabricated with five different additive machines and four materials using process parameters recommended by the manufacturers. The as-built geometry was measured non-destructively with computed tomography (CT) scans. To evaluate surface roughness, the coupons were cut-open and examined using a laser microscope. Three distinct roughness profiles on the coupon surfaces were captured including up-facing, down-facing, and channel walls built at 90 degrees to the build plate. Results indicated that both material and machine contribute to producing different roughness levels and very different surface morphologies. The roughness levels on the down-facing surfaces are significantly greater than on the up-facing or sidewall surfaces. Geometric analysis revealed that while the hydraulic diameter of all coupons was well captured, the pin cross section varied considerably. Along with characterizing the coupon surfaces, cooling performance was investigated by experimentally measuring friction factor and heat transfer. The variations in surface morphology as a function of material and machine resulted in heat transfer fluctuating by up to 50% between coupons featuring wavy channels and 26% for coupons with pin fin arrays. Increased arithmetic mean surface roughness led to increased heat transfer and pressure drop; however, a secondary driver in the performance of the wavy channels was found to be the roughness morphology, which could be described using the surface skewness and kurtosis.
Investigating the Unsteady Dynamics of a Multi-Jet Impingement Cooling Flow Using Large Eddy Simulation
Authors: Morsbach Christian , Matha Marcel , Brakmann Robin G. , Tabassum Sadiya , Bergmann Michael , Schroll Michael , Willert Christian , Kügeler Edmund 
Published: August 2024

Abstract
We investigate the unsteady behavior of an in-line jet impingement array of nine jets at a Reynolds number of 10 000 in a narrow channel subjected to a developing cross flow of up to 25% of the bulk jet velocity. To this end, we present an improved version of a previously published large eddy simulation (LES) now with resolved turbulence at the inflow boundaries. After a careful analysis of the transient behavior and statistical convergence of the LES, we discuss the time-averaged heat transfer characteristics of the configuration compared to numerical references of similar configurations. We then show how the large-scale unsteadiness increases from jet to jet. Both space-only and spectral proper orthogonal decompositions (POD and SPOD) are used to discuss the large-scale organization of single jets and multiple jets in combination. The latter shows a qualitative change in the unsteady behavior of the temperature footprint on the impingement wall with increasing cross flow.
High Speed H2 Centrifugal Compressor: a General Review of Journal Bearing Design and Experimental Validation
Authors: Vannini Giuseppe , Giannelli Carolina , Matina Dario , Cangioli Filippo 
Published: August 2024

Abstract
Hydrogen (H2) service is an emerging trend of Energy Transition, and centrifugal compressors will be effectively used to support the H2 production and transport chain. From a Turbomachinery design viewpoint, H2 compression yields many technical challenges spanning almost all the engineering disciplines involved (e.g., thermodynamics and materials, to name but a few) and this paper is focusing on the rotordynamic aspects and bearing design.
For this compression service, stacked rotor technology is used, which allows a higher impeller tip speed, and thus a higher compressor head, to be achieved with the same machine size and mechanical limitations of the rotor material compared to a conventional shrink fit assembly. From a rotordynamic and bearing design perspective, the main implications of achieving a high rotor peripheral speed are:
• Increased rotor flexibility: the rotor transitions through many rotor modes before reaching the operating speed, and they must be adequately damped.
• High journal surface peripheral speed: this must be managed from both thermal and rotordynamic viewpoint.
To meet the applicable design requirements based on API 617, the Authors adopted Flexure Pivot journal bearings with Integral Squeeze Film Dampers.
This paper shows, through a dedicated rotordynamic study, how the Flexure Pivot journal bearing with Integral Squeeze Film Dampers enable a rotodynamic design that fully complies with the requirements and moreover offers some new experimental data to confirm the validity of the design.
Finally, the paper shows how this bearing technology is ready to support even the next generation of H2 compressors, in which the peripheral speed of the rotor will be further increased using new higher strength materials.