bluuebunny/crossref_metadata_2025_split huggingface dataset:
A 23‐million‐year record of morphological evolution within Neotropical grass pollen
Authors: Wei Caixia , Li Mao , Mao Limi , Mander Luke , Jardine Phillip E. , Gosling William D. , Hoorn Carina 
Published: October 2024

Summary
Grass‐dominated biomes in South America comprise c. 20 million years of history, yet their evolution and underlying drivers remain poorly understood.
Here we apply a novel approach that combines scanning electron microscopy imaging with computational analysis to quantify the morphometrics of grass (Poaceae) pollen micro‐ornamentation from the Neotropics since the Early Miocene (23 million years ago). Three spatial–temporal pollen sets were assembled to further elucidate the variation and evolutionary traits of grasses through space and time.
Our results reveals that three spatial–temporal pollen groups occupy unique, partially overlapping regions of their exine morphospace. The direction of this shift is consistent over time, progressing towards less dense ornamentation. Interestingly, the extent of the occupied morphospace did not vary significantly. This is the first time that the true morphological variation in Poaceae pollen micro‐ornamentation becomes apparent through time.
We hypothesize that changes in grass pollen exine since the Early Miocene were driven by evolutionary processes (evolutionary drift and/or directional selection), and potentially migration at the continental scale. The high diversity in pollen micro‐ornamentation is likely related to their evolutionary success in the Neogene.
Stretched Vascular Endothelial Cells Polarized Neutrophils to N2 Type via TRPC1‐IL13‐STAT3 Axis
Authors: Jiang Ting , Chen Jiayi , Ouyang Ningjuan , Tang Guohua 
Published: October 2024

ABSTRACTObjectiveVECs play a crucial role in regulating the function of neutrophils, which is essential for immune responses and inflammation. As stretch‐sensitive cells, VECs sense mechanical stretch through surface mechanoreceptors, converting external mechanical stimuli into biochemical signals. This study aimed to explore the molecular mechanisms underlying the regulation of neutrophil behavior by stretched VECs.Materials and MethodsThe key cytokine‐inducing neutrophil N2 polarization in the conditioned medium from stretched vascular endothelial cells (CM‐stretch) was validated through multifactorial matrix and flow cytometry. Additionally, the molecular mechanism underlying the response of vascular endothelial cells to stretch was systematically verified through layer‐by‐layer analysis using WB.ResultsIL13, not IL4, was ultimately identified as a key cytokine‐inducing neutrophil N2 polarization in CM‐stretch. Inhibition of the transient receptor potential channel (TRPC1) and siRNA‐mediated knockdown of TRPC1 both significantly decreased IL13 production. Furthermore, neutralizing IL13 in the CM‐stretch or inhibiting STAT3 phosphorylation inhibited neutrophil N2 polarization, as evidenced by reduced CD206 and VEGFA expression.ConclusionsThese results demonstrate that stretched VECs initiate a signaling cascade that induces neutrophil N2 polarization through the TRPC1‐IL13‐STAT3 axis, suggesting that mechanical stretching of VECs could shift neutrophil function from a pro‐inflammatory to a more regulatory and healing role.
Salivary Extracellular Vesicles Separation: Analysis of Ultracentrifugation‐Based Protocols
Authors: Itzel Castillejos‐García , Eduardo Martínez‐Martínez , Velia Ramírez‐Amador , Mireya Cisneros‐Villanueva , Alfredo Hidalgo‐Miranda , Pilar Ramos‐Godínez María del , Gabriela Anaya‐Saavedra 
Published: October 2024

ABSTRACTIntroductionThe clinical potential of extracellular vesicles (EVs) is widely acknowledged, yet the standardization and reproducibility of its separation remain challenging. This study compares three protocols: ultracentrifugation (UC), UC with purification step (UC + PS), and a combined protocol using polymer‐based precipitation and UC (PBP + UC).MethodsSalivary samples were collected from healthy donors. EVs were separated (UC, UC + PS, and PBP + UC) and characterized using transmission electron microscopy, nanoparticle tracking analysis, EV purity, RNA concentration, and Western blotting. miRNA expression was evaluated by quantitative RT‐PCR. Statistical analyses comparing groups were performed using ANOVA.ResultsAll methods successfully separated CD9+ and CD63+ EVs from saliva. The UC + PS and PBP + UC protocols yielded the highest concentrations of EVs, enriched in < 200 nm vesicles. EV purity and RNA recovery were comparable among all methods. Expression of miR‐16, miR‐27a, and miR‐99a was successfully detected using all methods.ConclusionsThe UC + PS and PBP + UC protocols demonstrate comparable efficiency in separating salivary EVs. However, the combined PBP + UC protocol, with its simplified processing capability, offers a significant advantage, particularly in the initial phase of EV separation. This finding suggests its potential application in clinical settings where time‐sensitive simple processing is critical. Further validation is needed to confirm its effectiveness for transcriptomic and proteomic analyses.
Optimal designs for testing pairwise differences: A graph‐based game theoretic approach
Authors: Singh Arpan , Singh Satya Prakash , Davidov Ori 
Published: October 2024

AbstractIn a variety of experimental settings there is an interest in comparing pairs–of–treatments. Such experiments usually address one of the following two scientific questions: (1) is there a difference within any of the selected pairs of treatments? or (2) is there a difference within all of the selected pairs of treatments? In this article, we propose max–min optimal designs for testing the above hypotheses using a graph‐based game theoretic approach. Some of the max–min designs obtained are well known, but not recognized as optimal, others are novel and provide an improvement over naive designs.
Expansion and Strength Evolution Mechanism of Granite-Based Geopolymer Based on the Reactivity of Calcium Expansive Agents
Authors: Gomado Foster Dodzi , Agista Madhan Nur , Khalifeh Mahmoud 
Published: October 2024

Abstract
In this article, the role of the reactivity of different heat-treated calcium oxides on the properties of a granite-based geopolymer was investigated for low-temperature application to attain high linear expansion and its strength as well as understanding the probable underlying mechanism. The reactivity of the calcium oxide was investigated using the combination of isocalorimetry and BET. The heat-treated calcium oxides were classified as low reactive, medium reactive, and highly reactive with respect to their heat release in water. In addition to this, the resultant effect of the heat-treated calcium oxide was explored in terms of the exothermic behavior, linear expansions, compressive strength, and the pore volume distribution at a dosage of 0.1 wt% of the solid phase of the geopolymer mix. The results indicate that the different reactivities of the calcium oxide impact the linear expansion as well as the compressive strength. The different reactive calcium oxides improved the linear expansion by at least 100%. However, the low reactive calcium tends to decrease the compressive strength by 35% as a result of overexpansion. Therefore, this calls for the optimization of the reactivity of CaO for its application geopolymer for the best properties.
Adaptive Shock Control Bump With Shape Memory Alloy Wires on a Morphing Spoiler
Authors: Künnecke Sven Christian , Riemenschneider Johannes , Monner Hans Peter 
Published: October 2024

Abstract
Conventional transport aircraft operate under transonic conditions in which the transonic shock leads to an increase in wave drag. Shock control bumps (SCBs) can mitigate the shock strength, leading to reduced drag. Preceding studies show the applicability of adaptive SCBs on morphing spoilers. However, with increasing airflow velocities the shock moves downstream, making it structurally challenging to realize sufficient curvature on the rear spoiler end.
In this study, a morphing spoiler is structurally designed to form an adaptive SCB utilizing a shape memory alloy (SMA) actuator. A fiberglass composite structure is constructed to enable a form variable region, sufficiently stiff for handling aerodynamic loads but flexible enough for SMA actuation. To prevent the spoiler trailing edge lifting from the flap during bump deployment, a structural pre-bend is implemented on three regions. However, for SCB crest locations near the spoiler rear end, a strong pre-bend would be required, leading to significant contour deviations and waviness in clean configuration with retracted bump.
An additional actuator combined with structural pre-bends can enable more downstream bump crest locations than a single spoiler actuator. Since installation space for this additional actuator may be limited, SMAs are considered in this work. In modeling the two-way effect of the SMA, a simplified methodology is utilized. Despite the observed stress limits within the SMA wire being exceeded, the results demonstrate potential and indicate the possible utility of SMA for adaptive shock control on aircraft spoilers.
Nonlinear Effect in Physical Reservoir Computing Using a Mechanical Oscillator
Authors: He Shan , Musgrave Patrick 
Published: October 2024

Abstract
Physical reservoir computing (PRC) has emerged as a promising machine learning technique owing to its simplified training and minimal computational demands. When applied to mechanical systems, such as autonomous vehicles, PRC offers potential for efficient on-board processing of sensory data. Despite the benefits of PRC, there remains an absence in designing of mechanical systems that effectively embody reservoir computing for optimizing prediction performance. PRC leverages the nonlinear dynamics of a physical system to predict spatiotemporal input-output relationships, where the majority of the information is processed within the physical body of the system itself, thus achieving computational efficiency. This simple training process and low computational requirements enable real-time sensing and rapid decision-making in autonomous mechanical systems. To design optimal mechanical systems as physical implementation of reservoir computing, it is necessary to understand how the physical properties of these systems affect their ability to process information.
In this study, we investigated the relationship between the nonlinearity and the information processing capability of a one-dimensional Spring-Mass-Damper (SMD) network as a physical implementation of reservoir computing. We established a numerical model of the SMD network as a test system and conducted a parametric study by tuning the nonlinear spring stiffness of the system. Using a benchmark task of 2nd-order Nonlinear Autoregressive Moving Average (NARMA-2), we generated a target output for performance evaluation. We trained the system using linear regression to determine a set of optimal weights which relate between the target output and the mass displacement readouts. We then estimated the output using a linear summation of the displacement readout signals with their corresponding trained weights. We computed the prediction accuracy using a performance metric of R2 error between the target output and the estimated output. Our result indicates that optimal level of nonlinearity in the springs of the SMD system significantly improves PRC prediction performance. However, both linear and overly nonlinear systems result in poor performance. These findings emphasize the importance of a balanced level of nonlinearity in the SMD system’s dynamics, as it significantly influences its ability to process information and the PRC prediction. This study deepens our understanding of how nonlinearity affects PRC performance, providing insights for the design of optimal mechanical structures to serve as effective physical reservoir computers.
Structural Design and Optimization of Piezo-Activated Morphing CFRP Fan Blades
Authors: Kleinwechter Felix , Seidler Marcel , Monner Hans Peter , Friedrichs Jens 
Published: October 2024

Abstract
Modern aeronautical engines and their fans are currently conceived for optimal performance at a design point defined by the conditions of the dominant flight phase. Due to the resulting fixed blade geometry, engine efficiency is reduced during off-design conditions. A switch to shape-adaptive blades enables the adjustment of the geometry to prevailing conditions, increasing efficiency. Therefore, a methodology was developed for the design of piezo-activated morphing metallic engine blades within the Sustainable and Energy-Efficient Aviation SE2A Cluster of Excellence. To cover more off-design conditions, it is necessary to increase the morphing deformations. This paper introduces an extension of the methodology that enables the design of blade bodies from plies of carbon fiber-reinforced polymers. The goal is to use the anisotropic material properties of these composites to increase the achievable morphing deformations. A genetic algorithm is used to optimize the carbon fiber orientations of two fan blade architectures to maximize the morphing related change in turning angle or stagger angle. These tailored morphing composite fan blades achieve higher angular changes at a lower mass compared to titanium alloy blades.
Systematic, Scalable Manufacturing Process for Rolled Dielectric Elastomers
Authors: Weber Tobias , Kunze Julian , Faupel Benedikt , Motzki Paul 
Published: October 2024

Abstract
Dielectric elastomers (DEs) have emerged as promising materials for next-generation soft actuators and artificial muscles, due to their remarkable electromechanical properties, such as low power consumption and high energy density. Due to their sensitivity and wide sensing range, they can also be used as sensors. Among various DE configurations, coreless rolled dielectric elastomer actuators (RDEAs) play a significant role due to their unique advantages in terms of manufacturing efficiency and enhanced performance. This contribution presents the innovations and advancements in the scalable manufacturing process of RDEAs. The goal is to be able to produce them more efficiently, with the eventual goal of series production. We have successfully addressed challenges related to uniformity, scalability, and reproducibility, paving the way for RDEAs to become a viable option for large-scale applications and bundling of multiple RDEAs, for example in valve applications and concert subwoofers. This contribution aims to stimulate further research and collaboration in this rapidly evolving field, ultimately contributing to the development of more efficient and versatile soft actuation technologies.
A Novel Tactile Feedback Wristband Based on a Dielectric Elastomer
Authors: Roth Lukas , Croce Sipontina , Baltes Matthias , Nalbach Sophie , Motzki Paul 
Published: October 2024

Abstract
Smart wearable devices are becoming increasingly popular in daily life due to recent technological advances. They have various applications in the medical field (e.g., heart rate monitoring, blood pressure, blood oxygen), industrial field (e.g., worker assistance, gesture-based process control, recognition of unsafe conditions), and in the field of interactive virtual games (e.g., virtual reality, augmented reality). However, these devices must achieve their goals while meeting human needs during their use, such as wearability and adaptability. They must therefore be flexible, lightweight, and easy to understand with an intuitive interface. To fulfil these requirements, the challenge is to integrate flexible sensors and actuators into common clothing fabrics, minimizing the hardware needed and maximizing the wearer’s comfort.
In this paper, we present a novel dielectric elastomer (DE)-based wearable device that can provide tactile feedback on its wearer. It consists of a pouch-like air pocket with a passive and an active silicone membrane (DE). This pouch or bubble is inflated with air pressure, which acts as the necessary bias mechanism pre-stretching both the passive and the active DE membrane. The device is designed in a way that the passive membrane side of the pouch is in contact with the wearer’s skin.
In addition, to better understand how the passive membrane affects the overall system behavior, we provide experimental characterization studies on design parameters (i.e., thickness and initial pretension of the passive silicone membrane) for different internal pressure values. This results in the membranes having many layers with no pretension to minimize leakage.
A Conceptual Development of an Active Camber Morphing Airfoil for an Improved Aerodynamic Performance With Flexible Cellular Skin
Authors: Soltane Meryem , Restrepo Vanessa 
Published: October 2024

Abstract
Driven by the need to improve the performance and energy efficiency of aircraft, morphing wings became a promising bioinspired solution with its potential to continuously alter the wing shape for optimal efficiency at any flight condition. A primary challenge on the road to this feature is the realization of a flexible skin with a smooth camber variation profile and a high load-bearing capacity in a balanced manner. Within this paper, a new concept of morphing wing design is proposed to meet performance requirements, consisting of a corrugated structure and an internal honeycomb core with a flexible surface bonded on both sides. The equivalent flexible skin is coupled with the skeleton mechanism of the design. The critical dimensions and parameters are optimized through a parametric study based on the 2D finite element model of the design. Subsequently, the computational fluid dynamics method is employed to analyze the aerodynamic performance of the morphing wing design. The present study demonstrates the effectiveness and potential of the proposed camber morphing concept which can be further tested experimentally to assess its performance.
Resonance-Optimized Dielectric Pump Demonstrator With Self-Sensing Based Pressure Feedback
Authors: Baltes Matthias , Croce Sipontina , Bruch Daniel , Motzki Paul 
Published: October 2024

Abstract
This paper introduces a method for obtaining pressure feedback in a resonance-optimized dielectric elastomer-based pump, employing a self-sensing approach. Despite their increasing relevance, achieving energy-efficient control and optimized operation within various load ranges remains a significant challenge for dielectric elastomer-based pumps. As a result, dielectric elastomer-based pumps, regardless of their advantages such as silent operation, light weight and cheap base materials, have not yet found use in many everyday applications. In this work, the first step is taken to solve this problem with the help of a self-sensing approach and thus lays the foundation for the design of an energy-efficient control of dielectric elastomer-based pumps.
To develop, investigate and validate the self-sensing approach a demonstrator is designed, which operates in resonance under maximum load conditions, thereby ensuring consistent attainment of the target pressure and efficient pump performance in this exact operating point. For lower load pressures, the pump is not yet optimized as the resonance shifts under these conditions, due to a pressure-dependent stiffness change of the entire system. Depending on the target volume, this may result in a longer duration to reach the target pressure with simultaneous increased energy consumption. Solving this issue is the missing step in making dielectric elastomer-based pumps suitable for everyday use.
For designing an optimized control strategy across the entire load progression, and the resulting varying system stiffness when building up the target pressure, it is essential to always know the exact pressure at the target volume, as the system stiffness is proportional to this pressure. Conventional pumps have the same issue, which is often solved with the help of external pressure sensors. The target of this work is to exploit the advantages of dielectric elastomers and use their self-sensing capability. With this self-sensing approach, the final goal is to develop an independent actuator system that can work smart, and energy optimized without external sensors.
In this work, the pressure generated within the target volume can be determined utilizing electrical characteristics’ measurements on the demonstrator, which works under the previously described conditions. With a real-time current measurement during operation, the pressure can be determined using a microcontroller. This approach is validated by additionally equipping the demonstrator with an external pressure sensor and investigation of the two feedback signals of the pressure in the target volume.
Even without a specific control strategy, this already enables the use of dielectric elastomer-based pumps in applications that require various specific target pressures, such as pneumatic actuators, vacuum pumps, massage pillows and many other pressure-controlled applications.
Data Driven 1D - Modal Dispersion Estimation in Hydraulic Fluid Media
Authors: Beals Matthew David , Gosavi Hrishikesh , Malladi Vijaya V. N. Sriram 
Published: October 2024

Abstract
Acoustics are commonly analyzed using a source-path-receiver paradigm, in which the source and receiver are often pre-determined by design requirements. Consequently, the characteristics of the path typically have the most significant effect on the acoustic profile developed by a dynamic system. In particular, the wave propagation characteristics of the medium are critical for analyzing the propagation of noise through a system. As a result, understanding the behavior of wave propagation within a medium is essential to characterize the acoustic properties exhibited by a system. The most relevant of these characteristics is the speed at which a wave propagates, which can be derived from the relationship between spatial wavenumber and cyclic frequency. Current testing approaches rely on time-of-arrival, or “Pitch and Catch”, analysis which is limited to higher frequencies where reflection from boundaries does not interfere with time estimation. To accurately estimate arrival time, a sufficient number of wavelengths are required between measurement locations to allow measurable time to pass. This results in cumbersome and impractical testing conditions that are often unobtainable for low frequency measurements. To experimentally determine the relationship between wave number and frequency without relying on time-of-arrival methods, estimated acoustic mode shapes can be utilized to compute their spatial wave number. This wave number is plotted against the corresponding resonance frequency to form a dispersion curve. Multiple harmonic modes are measured to more accurately estimate dispersion properties across a range of frequencies. Acoustic modes are measured using a variable position hydrophone within a medium-filled wavetube to capture adequate measurements for dispersion estimation. Such a method removes the necessity for multiple wavelengths between measurement locations and allows for measurements to be taken at the lowest resonance frequency of the wave tube, enabling a compact test bench that can be utilized across a wider range of frequencies and mediums. By taking advantage of standing waves within a wavetube rather than avoiding them, a simpler testing method can be employed to extract clearer dispersion information across more frequencies than traditional estimation techniques.
The Meiotic Drive: Intragenomic Competition and Selection
Authors: Zakharov I. A. 
Published: October 2024

Abstract
The article considers the distribution and mechanisms of the meiotic drive as a phenomenon manifested in unequal transmission of gene alleles and/or homologous chromosomes into gametes during meiosis. The meiotic drive has been studied in the most detail in Drosophila, mice, corn, and ascomycete fungi of the genera Neurospora and Podospora. The consequence of the meiotic drive is a shift in the frequencies of alleles in the gene pool and the maintenance of nonadaptive traits in the population.