bluuebunny/crossref_metadata_2025_split huggingface dataset:
A fair go? How belief in a just world shaped attitudes, intentions, and behaviors before and after the Australian referendum on a First Nations voice to parliament
Authors: Bartholomaeus Jonathan , Strelan Peter 
Published: August 2024

AbstractIn October 2023, Australia voted on whether to enshrine in the constitution an Aboriginal and Torres Strait Islander “Voice” to Parliament. Debate around the Voice raised questions of justice and deservingness for a marginalized group within Australian society. The belief in a just world, the perception of fairness in this world for others (BJW‐other) and the self (BJW‐self), was, therefore, central to how people formed and expressed their opinions. In this longitudinal study (N = 253), we examined associations between BJW‐other, BJW‐self, and attitudes, intentions, and actions towards the Voice before and after the vote. Analysis indicated broadly negative associations between T1 BJW‐other and pro‐Voice outcomes (at both timepoints), while BJW‐self was positively related. Findings were, however, inconsistent when controlling for a broad range of sociopolitical covariates. These findings make an important contribution to justice motive theory by illustrating the role of justice beliefs in the political context.
Production of Four‐Gene (GTKO/hCD55/hTBM/hCD39)‐Edited Donor Pigs and Kidney Xenotransplantation
Authors: Yang Chang , Wei Yunfang , Li Xinglong , Xu Kaixiang , Huo Xiaoying , Chen Gang , Zhao Heng , Wang Jiaoxiang , Wei Taiyun , Qing Yubo , Guo Jianxiong , Zhao Hongfang , Zhang Xiong , Jiao Deling , Xiong Zhe , Jamal Muhammad Ameen , Zhao Hong‐Ye , Wei Hong‐Jiang 
Published: August 2024

ABSTRACTBackgroundThe number of multigene‐modified donor pigs for xenotransplantation is increasing with the advent of gene‐editing technologies. However, it remains unclear which gene combination is suitable for specific organ transplantation.MethodsIn this study, we utilized CRISPR/Cas9 gene editing technology, piggyBac transposon system, and somatic cell cloning to construct GTKO/hCD55/hTBM/hCD39 four‐gene‐edited cloned (GEC) pigs and performed kidney transplantation from pig to rhesus monkey to evaluate the effectiveness of these GEC pigs.ResultsFirst, 107 cell colonies were obtained through drug selection, of which seven were 4‐GE colonies. Two colonies were selected for somatic cell nuclear transfer (SCNT), resulting in seven fetuses, of which four were GGTA1 biallelic knockout. Out of these four, two fetuses had higher expression of hCD55, hTBM, and hCD39. Therefore, these two fetuses were selected for two consecutive rounds of cloning, resulting in 97 live piglets. After phenotype identification, the GGTA1 gene of these pigs was inactivated, and hCD55, hTBM, and hCD39 were expressed in cells and multiple tissues. Furthermore, the numbers of monkey IgM and IgG binding to the peripheral blood mononuclear cells (PBMCs) of the 4‐GEC pigs were markedly reduced. Moreover, 4‐GEC porcine PBMCs had greater survival rates than those from wild‐type pigs through complement‐mediated cytolysis assays. In pig‐to‐monkey kidney xenotransplantation, the kidney xenograft successfully survived for 11 days. All physiological and biochemical indicators were normal, and no hyperacute rejection or coagulation abnormalities were found after transplantation.ConclusionThese results indicate that the GTKO/hCD55/hTBM/hCD39 four‐gene modification effectively alleviates immune rejection, and the pig kidney can functionally support the recipient monkey's life.
Crossing numbers of cable knots
Authors: Kalfagianni Efstratia , Mcconkey Rob 
Published: August 2024

AbstractWe use the degree of the colored Jones knot polynomials to show that the crossing number of a ‐cable of an adequate knot with crossing number is larger than . As an application, we determine the crossing number of 2‐cables of adequate knots. We also determine the crossing number of the connected sum of any adequate knot with a 2‐cable of an adequate knot.
Presynaptic quantal size enhancement counteracts post‐tetanic release depression
Authors: Nair Anu G. , Bollmohr Nasrin , Schökle Levin , Keim Jennifer , Melero José María Mateos , Müller Martin 
Published: August 2024

AbstractRepetitive synaptic stimulation can induce different forms of synaptic plasticity but may also limit the robustness of synaptic transmission by exhausting key resources. Little is known about how synaptic transmission is stabilized after high‐frequency stimulation. In the present study, we observed that tetanic stimulation of the Drosophila neuromuscular junction (NMJ) decreases quantal content, release‐ready vesicle pool size and synaptic vesicle density for minutes after stimulation. This was accompanied by a pronounced increase in quantal size. Interestingly, action potential‐evoked synaptic transmission remained largely unchanged. EPSC amplitude fluctuation analysis confirmed the post‐tetanic increase in quantal size and the decrease in quantal content, suggesting that the quantal size increase counteracts release depression to maintain evoked transmission. The magnitude of the post‐tetanic quantal size increase and release depression correlated with stimulation frequency and duration, indicating activity‐dependent stabilization of synaptic transmission. The post‐tetanic quantal size increase persisted after genetic ablation of the glutamate receptor subunits GluRIIA or GluRIIB, and glutamate receptor calcium permeability, as well as blockade of postsynaptic calcium channels. By contrast, it was strongly attenuated by pharmacological or presynaptic genetic perturbation of the GTPase dynamin. Similar observations were made after inhibition of the H+‐ATPase, suggesting that the quantal size increase is presynaptically driven. Additionally, dynamin and H+‐ATPase perturbation resulted in a post‐tetanic decrease in evoked amplitudes. Finally, we observed an increase in synaptic vesicle diameter after tetanic stimulation. Thus, a presynaptically‐driven quantal size increase, likely mediated by larger synaptic vesicles, counterbalances post‐tetanic release depression, thereby conferring robustness to synaptic transmission on the minute time scale.
imageKey points
Many synapses transmit robustly after sustained activity despite the limitation of key resources, such as release‐ready synaptic vesicles.
We report robust synaptic transmission after sustained high‐frequency stimulation of the Drosophila neuromuscular junction despite a reduction in release‐ready vesicle number.
An increased postsynaptic response to individual vesicles, likely driven by an increase in vesicle size due to endocytosis defects, stabilizes synaptic efficacy for minutes after sustained activity.
Our study provides novel insights into the mechanisms governing synaptic stability after sustained neural activity.
Development of a Hydrogen Microgas Turbine Combustor: NOx Emissions and Secondary Air Injection
Authors: Tanneberger Tom , Mundstock Johannes , Rösch Sebastian , Rex Christoph , Paschereit Christian Oliver 
Published: August 2024

Abstract
On the way to defossilization, green hydrogen is a promising way to substitute natural gas (NG) and oil in the gas turbine industry. In the scope of the H2mGT project, a microgas turbine (mGT) burner with 100% hydrogen firing is developed and validated. The project is funded by the German BMWK, and it is a collaboration between Technische Universität Berlin (TUB) and the manufacturer Euro-K GmbH. It consists of three phases: (1) atmospheric pressure tests with a fused silica combustion chamber; (2) atmospheric pressure tests with counterflow-cooled steel flame tube and secondary air injection; (3) validation of the burner in the mGT at elevated pressure levels. The current study will present the results of phase 2. The hydrogen burner used in the project is based on a swirl-stabilized burner of TUB and was scaled to 36 kW thermal power at atmospheric conditions. The burner design features a variable swirl intensity, additional axial momentum of air in the mixing tube, a movable central fuel lance, and pilot nozzles at the front plate. Furthermore, the steel flame tube is exchangeable, which allows the evaluation of different dilution hole patterns and, thus, the variation of the ratio of primary and secondary air. The study presents temperature, pressure, and emission measurements. It is found that the flame can be operated over a large range of equivalence ratios and preheating temperatures up to 500 °C. As expected, the NOx emissions are mainly influenced by the local equivalence ratio, which can be controlled by the fuel mass flow or the dilution hole pattern in the flame tube. Furthermore, the results show a decrease of NOx when the power density is increased at constant equivalence ratios, and a rise of NOx during the fuel transition from natural gas to hydrogen. The results indicate certain differences to the findings of phase 1.
Synergetic and Performance Characteristics of a High-Speed Precooled Propulsion Concept
Authors: Chatzistefanou Athanasios , Tsentis Spyros , Kalfas Anestis 
Published: August 2024

Abstract
Precooled air-breathing cycles are promising candidates to power future high-speed flight as well as single-stage-to-orbit vehicles, due to their increased efficiency over contemporary propulsion systems and launch vehicles. These concepts usually feature complex interactions in the synergy of their thermodynamic cycles, which are not yet well understood, especially at off-design conditions. In this study, a performance model for a precooled, hybrid, air-breathing, rocket-cycle engine is developed for its air-breathing mode of operation. One-dimensional thermodynamic modeling is employed within a component-level approach, to evaluate the performance and operation of the cycle under investigation in the range of 1.35≤M∞≤5 and conditions of up to 26 km altitude. The model is validated quantitatively and qualitatively for both design and off-design conditions. The specific impulse Isp and specific thrust Fspec, as predicted by the model, agree within less than 5% for the design-point conditions at M∞ = 5. At off-design conditions, the model captures the trend of Isp and agrees within less than 1% with respect to the data for the maximum value of Isp. The maximum gross thrust Fgross point is predicted correctly at M∞=4. The fundamental operating principles and synergetic characteristics of the engine at design and off-design conditions are investigated and reported. Parametric analyses quantify the influence of the engine's parameters on the leading performance metrics. A model which does not feature a bypass duct is created and compared for the same inflow conditions and mission profile. It is found that the engine without the bypass duct exhibits reduced specific impulse which can be up to 32% lower at off-design conditions. In addition, the corresponding fuel mass flowrate to achieve the same mission is increased by a factor of 1.5. It is demonstrated that the overall trend of engine efficiency cannot be properly captured without modeling of the bypass duct, especially at the region of M∞&lt;3.5, where the ramjet-like operation is critical. This highlights the importance of the bypass, which is typically neglected in the modeling of such high-speed, combined-cycle systems.
A High-Speed, High-Temperature, Micro-Cantilever Steam Turbine for Hot Syngas Compression in Small-Scale Combined Heat and Power
Authors: He Victoria , Van Herle Jan , Schiffmann Jürg 
Published: August 2024

Abstract
Coupling a biomass gasifier with a solid oxide fuel cell system through a high-temperature syngas compressor holds great promise to achieve low-emission, small-scale combined heat and power, since it reduces the number of heat exchangers and increases the system efficiency. However, due to the demanding operating conditions (high temperatures, toxic and explosive gases), electrical motors are not suitable to drive the syngas compressor. Therefore, a high-speed, small-scale cantilever steam turbine that can valorize the system's waste heat to power the compression is designed and developed. An iterative holistic process involving preliminary design, meanline analysis, commercial tools, and in-house codes is used for the design. The design is then numerically analyzed using computational fluid dynamics. The 2.8 kW cantilever steam turbine with a tip diameter of 21 mm runs up to 210 krpm at temperatures of 525 °C while being supported on dynamic steam-lubricated bearings. A low-reaction, full-admission design has been chosen to lower the steam consumption, the axial forces, and the turbine backface leakage. The turbine rotor is made of Ti6Al4V and coated for structural integrity and to withstand high temperatures. Despite the small scale of this design, the results obtained from the established correlations based on large-scale turbines yield a remarkable concordance with the results from the numerical analysis, in particular for the isentropic expansion efficiency prediction.
A High-Temperature, High-Speed, Oil-Free Syngas Compressor for Small-Scale Combined Heat and Power
Authors: He Victoria , Van Herle Jan , Schiffmann Jürg 
Published: August 2024

Abstract
For low-emission, small-scale combined heat and power generation, integrating a biomass gasifier with a downstream solid oxide fuel cell system is very promising due to their similar operating conditions in terms of temperatures and pressures. This match avoids intermediate high-temperature heat exchangers and improves system efficiency. However, to couple both systems, a high-temperature and oil-free compressor is required to compress and push the low-density, high-temperature biosyngas from the gasifier to the solid oxide fuel cell stack. The design and development of this high-temperature, high-speed, and gas-bearing supported compressor is presented in this work. A holistic iterative process involving preliminary design, meanline analysis using commercial tools and in-house models is used for the design, which is then numerically analyzed using computational fluid dynamics. The goal is to achieve a design with a wide operating range and high robustness that withstands extreme working conditions. The 727 W machine is designed to run up to 210 krpm to compress 18.23 kg h−1 of syngas at 350 °C and 0.81 bar. The centrifugal compressor has a tip diameter of 38 mm and consists of 9 backswept main and splitter blades. The impeller is made of Ti6Al4V and coated to prevent hydrogen embrittlement from the hot and highly reactive biosyngas. The results obtained from the established models suggest a good concordance with the results from numerical analyses, despite the high temperatures and small scale of this design.
Optimization of Smooth Straight-Through Labyrinth Seal Based on XGBoost and Improved Genetic Algorithm
Authors: Liu Hao , Li Guoqing , Kang Chenyang , Ruan Yunhong , Wang Ruofan , Lu Xingen 
Published: August 2024

Abstract
Improving the sealing performance of labyrinth seal is beneficial in reducing the loss of downstream components as well as improving the aero-engines' efficiency. Meanwhile, the optimization of labyrinth seal is more cost-effective than optimizing other components of aero-engines. Based on extreme gradient boosting (XGBoost) and improved genetic algorithm (GA), an automatic optimizer for smooth straight-through labyrinth seal is proposed. According to the ordering of feature importance, the ten selected geometric parameters of smooth straight-through labyrinth seals with two gaps (0.1 mm, 0.25 mm) are optimized when the axial length of labyrinth seal is limited. The optimization results show that the leakage rate of the optimized labyrinth seal with two gaps is 19.67% and 23.80% lower than the reference labyrinth seal, respectively. It is found that the decrease of fin height, fin angle, fillet radius, and fin width, and the increase of fin pitch are beneficial to improve the sealing performance of smooth straight-through labyrinth seal. The analysis of flow field reveals the reasons for the improvement of sealing performance due to the change of geometric parameters. However, it must be noted that the optimization effect decreases as the pressure ratio increases, primarily as the result of the increase in carry-over coefficient. This work provides a new approach to optimize smooth straight-through labyrinth seal.
Investigation of the Coupling Between the Dynamics of Vortical Structures and Flame Stability in Bluff-Body Premixed Combustion Using Extended Spectral Proper Orthogonal Decomposition
Authors: Khalifehei Morteza , Yalcinkaya Yagiz , Padilla-Montero Iván , Gungor Ayse Gul , Rodríguez Daniel 
Published: August 2024

Abstract
Large eddy simulation data of a bluff-body stabilized flame are analyzed using spectral proper orthogonal decomposition (SPOD) to investigate: (i) the role of flame-vortex interactions in the dominant flow dynamics and (ii) how the proper choice of the cross-spectral density (CSD) defining SPOD can assist in identifying the underlying dynamics. Bluff-body flame holders aim to achieve stable flames under lean premixed conditions to minimize pollutant emissions. The recirculation region induced by the body promotes the mixing of hot combustion products with unburnt gases, preventing the global blowoff. However, the coupling between the shear layers and flame-induced vorticity sources can result in large flow structures that either contribute to increased flame stability or exhibit features typical of the early stages of flame blowout. SPOD is a data-driven technique remarkably powerful in extracting low-dimensional models. For each frequency, it computes a basis of orthogonal modes that maximizes the content of a predefined CSD in the leading modes. By choosing physically relevant variables to construct the CSD, different physics can be explored, which is used here to investigate the coupled dynamics between the flame-induced baroclinic torque, vortical structures, and the temperature field. The results show that the vorticity and temperature fields exhibit low-dimensional dynamics characterized by a narrowband frequency and its harmonics; these dynamics are varicose oscillations of the flame region, governed by the baroclinic torque. Sinuous oscillations typical of wake instability for nonreactive flows are also present, suggesting a competition between them.
Compressor Surge Identification in Innovative Heat-Pump Systems Equipped by Vaned Diffuser Centrifugal Compressor
Authors: Niccolini Marmont Du Haut Champ Carlo Alberto , Silvestri Paolo , Reggio Federico , Traverso Alberto , Sishtla Vishnu 
Published: August 2024

Abstract
In the present energy scenario, heat pumps (HPs) are assuming an important role to improve energy efficiency in reversible cooling systems. In particular, in case of industrial size plants, centrifugal compressors are preferred with respect to other solutions; nonetheless, they are often subjected to variable operation and therefore they must withstand off-design conditions. For studying unstable operation of refrigerant closed-loop systems, Carrier provided the University of Genoa with a small size chiller rig equipped with an innovative high speed centrifugal compressor driven by a variable speed motor. This paper presents the vibro-acoustic signature analysis of such a closed-loop rig from a system perspective, mainly focusing on mechanical response of compressor casing. First, its vibro-acoustic characterization is conducted at on-design and stable operation. Afterwards, some surge transients are obtained by progressively closing some valves in plant feeding lines, and meanwhile vibro-acoustic signals are acquired at relevant plant locations to characterize system response just before instability onset. In this way, suitable surge precursors can be defined in incipient surge conditions for early surge detection in this kind of complex plants. Indeed, system dynamics is significantly affected by interposed volumes, and therefore the effect of heat exchangers in system response may be relevant. To this aim, system dynamics is analyzed in detail both in subsynchronous frequency range and in high frequency region to assess how its vibro-acoustic response varies when moving from stable conditions toward surge. Surge precursors are obtained by relying only on vibro-acoustic signals both in low and high frequency ranges in order to perform early surge detection in such chiller pilot system. The main advantage of the proposed approach is to exploit nonintrusive probes, which allow to define diagnostic indicators without interacting directly with the working fluid, therefore preserving system integrity and reliability.
Silurian ocean island basalt magmatism and Devonian–Carboniferous polymetamorphism: 100 million years in the Western Blue Ridge, USA
Authors: Yasar I. Dogancan , Miller Brent V. , Hames Willis E. 
Published: August 2024

Abstract
The tectonic configuration and evolution of southern Appalachian orogenic episodes are constrained, to a large extent, by knowledge of the timing and environment of pre- or syn-orogenic sediment deposition along with their subsequent thermal and deformational histories. The orogenic events that gave rise to regional folding and Barrovian metamorphism of the Western Blue Ridge (WBR) terrane are a classic example. We present new U-Pb and 40Ar-39Ar results bearing on the timing of magmatism and subsequent metamorphism of the Marble Hill Hornblende Schist (MHHS) of the WBR (southeastern USA). The schist is a key marker unit in the Murphy synclinorium, a central structure in the tectonic configuration of the WBR. The MMHS originated as basaltic volcanics overlying the Murphy Marble at the base of the Mineral Bluff Group. Ocean island basalt geochemistry and a zircon U-Pb age of ca. 437 Ma for the MHHS is consistent with plume-related volcanism in a Silurian remnant ocean basin of the Iapetus Ocean. Hornblende 40Ar-39Ar and rutile U-Pb ages for the MHHS are ca. 380–340 Ma and ca. 320 Ma, respectively, and record subsequent amphibolite facies metamorphism during Devonian Acadian orogeny and the deformation through regional folding and thrusting during the Carboniferous Alleghanian orogeny. The new age constraints for the MHHS require that “isograds” mapped in the region of the Murphy Belt are actually polymetamorphic mineral distributions that developed at least in part through post-Silurian tectonic events.