bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutational biases favor complexity increases in protein interaction networks after gene duplication
Authors: Cisneros Angel F , Nielly-Thibault Lou , Mallik Saurav , Levy Emmanuel D , Landry Christian R 
Published: March 2024

AbstractBiological systems can gain complexity over time. While some of these transitions are likely driven by natural selection, the extent to which they occur without providing an adaptive benefit is unknown. At the molecular level, one example is heteromeric complexes replacing homomeric ones following gene duplication. Here, we build a biophysical model and simulate the evolution of homodimers and heterodimers following gene duplication using distributions of mutational effects inferred from available protein structures. We keep the specific activity of each dimer identical, so their concentrations drift neutrally without new functions. We show that for more than 60% of tested dimer structures, the relative concentration of the heteromer increases over time due to mutational biases that favor the heterodimer. However, allowing mutational effects on synthesis rates and differences in the specific activity of homo- and heterodimers can limit or reverse the observed bias toward heterodimers. Our results show that the accumulation of more complex protein quaternary structures is likely under neutral evolution, and that natural selection would be needed to reverse this tendency.
Asteroid reflectance spectra from Gaia DR3: Near-UV in primitive asteroids
Authors: Tinaut-Ruano F. , de León J. , Tatsumi E. , Morate D. , Mahlke M. , Tanga P. , Licandro J. 
Published: March 2024

Context. In the context of charge-coupled devices (CCDs), the ultraviolet (UV) region has mostly remained unexplored after the 1990s. Gaia DR3 offers the community a unique opportunity to explore tens of thousands of asteroids in the near-UV as a proxy of the UV absorption. This absorption has been proposed in previous works as a diagnostic of hydration, organics, and space weathering.
Aims. In this work, we aim to explore the potential of the NUV as a diagnostic region for primitive asteroids using Gaia DR3.
Methods. We used a corrective factor over the blue part of Gaia spectra to erase the solar analog selection effect. We identified an artificial relation between the band noise and slope and applied a signal-to-noise ratio (S/N) threshold for Gaia bands. Meeting the quality standards, we employed a Markov chain Monte Carlo (MCMC) algorithm to compute the albedo threshold, maximizing primitive asteroid inclusion. Utilizing one- and two-dimensional (1D and 2D) projections, along with dimensionality-reduction methods (such as PCA and UMAP), we identified primitive asteroid populations.
Results. We uncovered: (a) the first observational evidence linking UV absorption to the 0.7 µm band, tied to hydrated iron-rich phyllosilicates; and (b) a 2D space revealing a split in C-type asteroids based on spectral features, including UV absorption. The computed average depth (3.5 ± 1.0 %) and center (0.70 ± 0.03 µm) of the 0.7 µm absorption band for primitive asteroids observed with Gaia is in agreement with the literature values.
Conclusions. In this paper, we shed light on the importance of the UV absorption feature to discriminate among different mineralogies (i.e., iron-rich phyllosilicates vs. iron-poor) or to identify taxonomies that are conflated in the visible (i.e., F-types vs. B-types). We have shown that this is a promising region for diagnostic studies of the composition of primitive asteroids.
Exploring critical internal enablers to SMEs export performance: evidence from Qatar
Authors: Elsharnouby Tamer H. , Elbanna Said , Farha Allam Abu , Mauji Nasrina 
Published: March 2024

AbstractThis study seeks to provide a contextualized and nuanced understanding of what constitutes internal enablers among small and medium-sized enterprises (SMEs) in support of their export activities in international markets. We unpacked a unique set of critical enablers that can be cultivated as the internal impetus for enhancing the export performance of SMEs in a less-researched emerging market, Qatar. The study employs a qualitative approach for collecting, analyzing, and interpreting data, which were collected through in-depth interviews with 20 SMEs managers from 11 manufacturing sub-sectors. A thematic analysis of our data reveals five key internal enablers needed for better export performance. These comprise employees with networking skills, effective supply chain management, product diversification, digitalization, and market intelligence capabilities. This research offers empirical insights into what enables non-hydrocarbon manufacturing SMEs to enhance their export performance.
Characterization and modeling of plasma sheath in 2.45 GHz hydrogen ECR ion sources
Authors: Asadi Aghbolaghi M. , Abbasi Davani F. , Yarmohammadi Satri M. , Riazi Mobaraki Z. , Ghasemi F. , Castro G. 
Published: March 2024

In this article, we present a multi-fluid numerical model developed for application on electron cyclotron resonance ion sources (ECRIS). The 1D-model is matured to compute the density of the ion species in the plasma sheath in the presence of an inhomogeneous magnetic field of a 2.45 GHz ECRIS. The multi-fluid model in cylindrical coordinates is focused on solving the continuity and momentum equations of hydrogen plasma particles to characterize their sheath properties. In addition, 28 important processes, including volume and surface collisions, have been included in the COMSOL Multiphysics package to simulate the ECR plasma. We study the elementary processes containing electron–atom, electron–molecule, atom–molecule, molecule–molecule, and particle–wall interactions. Then, the results of the model and the simulation of a 2D-hydrogen plasma are reported, and future perspectives are discussed throughout the paper.
Strong electron correlation-induced Mott-insulating electrides of Ae5X3 (Ae = Ca, Sr, and Ba; X = As and Sb)
Authors: Xu Ya , Zheng Lu , Zhang Yunkun , Zhang Zhuangfei , Wang QianQian , Zhang Yuewen , Chen Liangchao , Fang Chao , Wan Biao , Gou Huiyang 
Published: March 2024

The presence of interstitial electrons in electrides endows them with interesting attributes, such as low work function, high carrier concentration, and unique magnetic properties. Thorough knowledge and understanding of electrides are thus of both scientific and technological significance. Here, we employ first-principles calculations to investigate Mott-insulating Ae5X3 (Ae = Ca, Sr, and Ba; X = As and Sb) electrides with Mn5Si3-type structure, in which half-filled interstitial electrons serve as ions and are spin-polarized. The Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons, resulting in spin splitting and a separation between occupied and unoccupied states. The half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these materials. Compared with that in intermetallic electrides, the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak, leading to highly localized magnetic centers and pronounced correlation effects. Therefore, the Mott-insulating electrides Ae5X3 have very large indirect bandgaps (∼0.30 eV). In addition, high pressure is found to strengthen the strong correlation effects and enlarge the bandgap. The present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.
A method to build feature descriptor for GNSS spoofing detection by carrier phase double difference measurement
Authors: Dinh Thuan Nguyen , Huu Truong Trinh , Van Hien Nguyen , The Vinh La , Ngoc Hung Pham , Hai Tung Ta , Hoang-Van Hiep 
Published: March 2024

Abstract
GNSS spoofing is a type of attack that aims to deceive GNSS receivers by transmitting fake signals that imitate the authentic ones. To detect such attacks, a possible solution is to calculate the double difference (DD) of carrier phase measurements between two antennas of two separated receivers. This DD measurement represents the angle of arrival (AoA) information of the signal. In the case of authentic signals, each signal comes from a different satellite, so the AoA values are different for each satellite. However, in the case of a spoofing attack, all the counterfeit signals from the same broadcaster come from the same direction, and thus the AoA values are the same for all DD measurements. Sum of Squares (SoS) detector and Dispersion of Double Difference (D3) detector are known as simple but effective methods for spoofing detection. However, these detectors are not robust in some special regions where cycle slips are large and vary rapidly. This paper proposes a new method for detecting GNSS spoofing by using carrier phase double difference measurements to generate a feature vector as a descriptor for each satellite in a set of observed satellites. The feature vectors are formed by statistical parameters of a series of consecutive double difference values computed for each reference satellite. Our proposed feature descriptor has been evaluated on a dataset containing both real and fake signals using an SVM classifier. The study shows that the proposed feature descriptor is highly effective in detecting spoofing satellite signals.
Influence of vacancy type defects on the exchange integrals in ferromagnetic metals: a Monte-Carlo-based approach
Authors: Billgates LeBert Sam , Joseyphus R Justin 
Published: March 2024

Abstract
Estimating exchange interactions in real systems, particularly with defects like vacancies and impurities, poses significant challenges. A classical Monte-Carlo spin simulation within an atomistic machine-learning framework is utilized to predict the pairwise exchange interactions in ideal and defective bcc Fe and fcc Ni systems. The results closely replicate the experimental Curie temperature, with a reduction in exchange interaction by ∼1 meV for the system with cluster vacancy concentration up to 6%. An exponential relationship is established between the classical rescaling parameter

α

and microscopic exchange interaction enhancing

α

up to 3.35 and 2.5 in Fe and Ni, respectively. Additionally, the spin wave stiffness constant calculated using the near neighbor Heisenberg model demonstrates a dampening in both Fe and Ni with the inclusion of cluster vacancies.
Wave-breaking limit of electrostatic waves in two-temperature electron-positron plasmas
Authors: Biswas Anubhab , Maity Chandan 
Published: March 2024

Abstract
Wave-breaking limit of high frequency electrostatic waves in a four-component two-temperature electron-positron (EP) plasma has been studied. Using Sagdeevs pseudopotential approach, the wave-breaking limit in such plasmas has been derived, taking into account the dynamics of both the hot and cool species. It is observed that the value of the limit is diminished in a two temperature EP plasma in comparison to a single-temperature one. The analysis also reveals that the wave-breaking limit is greatly influenced by the ratio of the equilibrium density of the hot species to the equilibrium density of the cool species, and the temperatures of the two species of the plasma. The results of this investigation is expected to have applications in astrophysical and space-plasma environments.
Enhancing broadband terahertz absorption via a graphene-based metasurface absorber featuring a rectangular ring and triple crossbars
Authors: Chou Chau Yuan-Fong 
Published: March 2024

Abstract
This study introduces an innovative strategy to achieve a versatile and adaptive terahertz (THz) absorber by leveraging a graphene-based metasurface. This metasurface comprises a rectangular ring, three crossbars and a grounded gold film, all separated by a thin SiO2 layer. The phenomenon of plasmonic hybridization, involving surface and cavity plasmon resonances, enables the interaction between incident THz waves and the proposed graphene-based metasurface, leading to a substantial enhancement in the absorptance bandwidth of the plasmonic system. The enhancement of absorptance can be finely adjusted by modifying the chemical potential (Fermi energy) in graphene and manipulating the structural parameters of the device. A notable feature of our design is its inherent resistance to variations in incident angles and polarization states of incoming electromagnetic waves. The proposed device achieves an absorptance exceeding 80% across a continuous spectrum, exhibiting a bandwidth of approximately 0.90 THz from 0.94 to 1.84 THz. This robust characteristic ensures consistent and reliable performance in diverse scenarios. Our findings present intriguing prospects for various applications centered on wave modulation, which encompass, but are not limited to, THz imaging, filtering, energy harvesting, and tunable sensors.
Compact and high gain cup-shaped 4-Port MIMO antenna using low profile material for the sub-6 GHz, IoT and military applications
Authors: Kannan T , Taher Fatma , Sree Mohamed Fathy Abo , Lavadiya Sunil 
Published: March 2024

Abstract
The article introduces a novel design of a miniaturised and high-gain 4-Port MIMO antenna ingeniously crafted as a cup. The evolution of the radiating structure, achieved through meticulous iterations involving alterations to the patch element’s shape and feedline modifications, underscores the commitment to optimal performance. Leveraging parametric analysis, which includes strategic adjustments to the ground layer’s length, incorporation of vertical and horizontal slots, and the addition of a parasitic patch in the top layer, our proposed framework spans the spectrum from 1 GHz to 14 GHz. The antenna exhibits a tripartite frequency response at 4.6 GHz, 8.7 GHz, and 13 GHz, showcasing a peak bandwidth of 5.5 GHz and a minimum return loss of −24.22 dB. Remarkably, the design achieves a peak gain of 8.32 dB, coupled with stellar performance in diverse parameters such as ECC, MEG, TARC, CCL, and DG. Constructed with low-profile FR4 material, the antenna thoroughly compares simulated and measured results, affirming its robust performance. This innovative architecture, poised for Sub6GHz, IoT, and military applications, not only pushes the boundaries of antenna design but also stands out as a significant advancement in the field.
Characteristics of pedestrian evacuation from narrow seated area considering exit failure: experimental and simulation results
Authors: Hu Xiangmin , Chen Tao , Wang Jianyu , Liu Xiang , Li Meng , Sun Zhanhui 
Published: March 2024

Abstract
Narrow seated spaces with multiple exits are prevalent structures in public buildings, underscoring the paramount importance of facilitating swift evacuation in such constrained environments. In this study, we first conducted evacuation experiments in a realistic narrow seated area. By manipulating different availability conditions for two exits located at the ends of the long aisle, we studied the effects of unpredictable exit failures, specifically, how the exit switch and explicit guidance influence the evacuation process. The movement characteristics are explored in several aspects, such as pre-evacuation time, aisle conflicts, speed, distance headway, evacuation time, and time lapse. We found that once people have encountered the exit failure condition, they would demonstrate enhanced preparedness in subsequent trials, leading to expedited exit switches. With explicit guidance, people would be less hesitant and move faster in the main aisle. The fine-grid cellular automata model is extended based on the experimental observations to verify its feasibility in simulating this process. Conflict resolution and turning behavior are incorporated for a more nuanced description. The effects of the exit switch are parameterized through the informed probability and the speed reduction.
Elastic and transport coefficients of the perfect hard-sphere crystal from the poles of the hydrodynamic spectral functions
Authors: Mabillard Joël , Gaspard Pierre 
Published: March 2024

Abstract
The elastic and transport coefficients of a perfect face-centered cubic crystal of hard spheres are computed from the poles of the dynamic structure factor and of the spectral functions of transverse momentum density fluctuations. For such crystals, the relevant coefficients are the three isothermal elastic constants

(

C

11

T

,

C

12

T

,

C

44

T

)

, the heat conductivity κ, and the three viscosities

(

η

11

,

η

12

,

η

44

)

(in Voigt’s notations), which are directly computed using molecular dynamics simulations. The elastic and transport coefficients are then compared to the values of the same coefficients obtained with the method of Helfand moments, showing good agreement and providing strong support for the microscopic hydrodynamic theory of perfect crystals based on the local-equilibrium approach.
Stochastic thermodynamics of Brownian motion in temperature gradient
Authors: Ding Mingnan , Wu Jun , Xing Xiangjun 
Published: March 2024

Abstract
We study stochastic thermodynamics of a Brownian particle which is subjected to a temperature gradient and is confined by an external potential. We first formulate an over-damped Ito-Langevin theory in terms of local temperature, friction coefficient, and steady state distribution, all of which are experimentally measurable. We then study the associated stochastic thermodynamics theory. We analyze the excess entropy production both at trajectory level and at ensemble level, and derive the Clausius inequality as well as the transient fluctuation theorem (FT). We also use molecular dynamics to simulate a Brownian particle inside a Lennard-Jones fluid and verify the FT. Remarkably we find that the FT remains valid even in the under-damped regime. We explain the possible mechanism underlying this surprising result.
Analysis of the influence of FDM parameters in the tensile strength response using machine learning
Authors: Cudris V , Santiago V J , Londoño C A , Lopez H 
Published: March 2024

Abstract
This research presents a comprehensive experimental study on the effect of temperature, material and process parameters related to tensile strength response in 3D printing manufacturing process with ABS material. A Hyper Latin Square design was chosen for the experimental points distribution. Thirteen parameters with multiple levels are considered LAYERHEIGHT, WALLTHICKNESS, TOPBOTTOMTHICKNESS, TOPBOTTOM-LINEDIRECTION1, TOPBOTTOMLINEDIRECTION2, INFILLDENSITY, INFILLLINEDI-RECTION1, INFILLLINEDIRECTION2, PRINTSPEED, EXTRUSIONTEMP, BEDTEMP, WORKSPACETEMP and POSITION. Type IV tensile specimens are fabricated and tested with an universal testing machine. Maximum stress is measured, evaluated and analyzed in three different building positions.Machine learning algorithm with Orange Data mining software are used to study underlying relations between factors and response. Experimental results indicate that INFILLDENSITY, TOPBOTTOMTHICKNESS and INFILLLINEDIRECTION1 has a strong positive correlation with tensile strength. Meanwhile, TOPBOTTOMLINEDI-RECTION1, WORKSPACETEMPERATURE and PRINTSPEED has a negative correlation with tensile strength. Position 1 with line depositions parallel to Y axis produce the higher tensile strength response. Findings imply that machine algorithms can be used to study multiple parameters at time.
Obtaining the percentages of ductility and brittleness of AISI/SAE 1020 and 304 steels, using digital image processing.
Authors: Rincon-Quintero A D , Lengerke O , Sandoval-Rodriguez C L , Jaimes Quintero K T 
Published: March 2024

Abstract
This research is the integration of a set of elements in a system of capturing, processing, and digital image analysis. It allows a better visual and numeric interpretation to determine the toughness, ductility percentage, and fragility of steel AISI/SAE 1020 and 30, getting better qualitative and quantitative observation of the results from the impact test (Charpy test). Patterns in the standard form, ASTM E23, were digitalized to evaluate the percentage of ductility/fragility of specimen testing. After, we calculated the area and the equivalent diameter of the material. using digital image processing and numerical comparison between the patterns specified in the standard form ASTM E23 and the testing in the impact test, and it allows to find the kind of pattern it is closest and determine which degree of ductility. Finally, the results were compared by three experts. The algorithm accuracy was 80%.
Finite element analysis of thermal sensitivity of copper nanorods, nanoellipsoids, nanospheres and core-shells for hyperthermia application
Authors: Daud Muhammad Usama , Abbas Ghulam , Afzaal Muhammad , Qamar Muhammad , Naz Muhammad Yasin , Irfan Muhammad , Rahman Saifur , Ghuffar Abdul , Magzoub Mohamed Ali Muawia Abdelkafi 
Published: March 2024

Abstract
Hyperthermia is a cancer treatment strategy that involves raising the temperature of the afflicted tissues without disrupting the surrounding tissues. This study is focused on finite element analysis of copper, nanoellipsoids, nanorods, nanospheres and core-shells for potential hyperthermia application. The temperature of copper nanostructures was elevated using an external source to the desired temperature to destroy the cancerous cell. The COMSOL Multiphysics package was used to calculate how long it would take to achieve the desired temperature using different nanostructures of copper. Thermal sensitivity of the tested nanostructures was checked by putting them in a spherical domain of tissue. It was observed that copper nano-rod attained the highest temperature of 43.3 °C compared to other geometries. It was also found that these geometries attained thermal equilibrium just after 0.5 μs. However, the copper nano-ellipsoid had a higher core volume, which is utilized to determine the thermal sensitivity of the nanostructures. Noble metal (Au) coating was first found to be better than PEG polymer coating for investigating core–shell structures. The Au coating on the surface of the copper core resulted in a gradual decrease in temperature with an increasing volume coverage ratio. These results conclude that copper nanostructures can be suitable candidates for hyperthermia.