bluuebunny/crossref_metadata_2025 huggingface dataset:
Internal transport barrier triggered by phase synchronization of zonal flow with energetic particle modes
Authors: Ghizzo A , Del Sarto D , Sama N J , Biancalani A
Published: December 2024

The suppression of the microturbulence associated to the emergence of a spontaneous internal transport barrier has been recently demonstrated in a system showing a possible amplification of the zonal flow component in the low-frequency regime (Ghizzo and Del Sarto 2023 Nucl. Fusion
63 104002). We use here numerical experiments performed with a ‘particles modes’ model based on a double average over the fast cyclotron phase and over the bounce (or transit) phase to show the major role played by energetic particles and shear flows in this scenario. ‘Particle modes’ are meant here as classes of particles, identified by some adiabatic invariant after a gyro-average procedure, which are associated to the description of some specific linear modes of the plasma. The introduction of energetic circulating ions or shear flows into the system makes a larger number of particle modes being involved in the synchronization process. A global synchronization of the Fourier modes of the turbulent spectrum can be this way achieved. This process allows for a bifurcation towards self-organization, which is associated to the emergence of a staircase-like structure. This is known to be an essential element in the modification of the zonal flow pattern in phase space during the suppression of microturbulence in tokamaks.
Continuous natural fiber-reinforced shape memory polymer biocomposites: design and fabrication for sustainable self-folding architectural applications
Authors: Hassan Asmaa , Dahy Hanaa
Published: December 2024

The growing demand for sustainable building materials has driven the search for innovative solutions that minimize environmental impact while enhancing architectural functionality. Nature’s adaptability to environmental changes, such as the mimosa plant’s sensitivity to temperature and touch, has inspired the development of shape memory materials like shape memory polymers (SMPs). These materials change shape in response to external stimuli, offering promising solutions for responsive and eco-friendly applications. This study investigates the use of SMP biocomposites (SMPBCs) reinforced with continuous flax fibers for sustainable architectural applications. The main aim is to enhance the mechanical and shape memory properties of these materials, focusing on design exploration, fabrication methods, and performance evaluation for architectural use. Combining material science with digital fabrication techniques, particularly tailored fiber placement, this research integrates flax fiber into thermo-responsive epoxy-based SMPs. Origami-inspired designs, including rigid and curved folding origami, were explored using a moldless fabrication technique to optimize the SMPBCs’ performance and facilitate the creation of complex three-dimensional structures. The study began with initial prototypes of simple origami shapes, followed by three architectural prototypes representing distinct origami types. Curved folding origami enhances shape memory performance by enabling larger deformation, which increases strain energy storage and allows more effective recovery. Further exploration of single and multi degree of freedom (SDOF and MDOF) designs for architectural applications revealed that curved SDOF prototypes achieved the highest shape recovery ratio (Rr
%) of 97%, while rigid MDOF prototypes showed the lowest Rr
of 60% and 70%. All prototypes provided a high shape fixity ratio of nearly 100%. Moreover, initial load tests on the permanent shapes demonstrated their ability to support over 240 times their weight. This research advances sustainable architecture by showing how SMPBCs with optimal geometric designs can enable self-shaping and multifunctional applications, paving the way for more adaptive, eco-friendly building materials.
Strain-induced interstitial anionic electrons and superconductivity of monolayer BaCu
Authors: Zhou Tong , Guan ZhiYao , Cui Tian , Li Da
Published: December 2024

Recently, a novel electride, BaCu, which contains no light elements, has been both predicted and synthesized. This material adds to the list of inorganic two-dimensional (2D) interlayer electrides, including Ca2N and Y2C. However, the electride properties of the BaCu monolayer are not known, and its characteristics have not been thoroughly investigated. Here, our first-principles calculations indicated that the BaCu monolayer is a weak electride with few interstitial anionic electrons (IAEs). Notably, biaxial tensile strain can significantly alter the electronic properties of the BaCu monolayer, leading to the increase of IAEs. This strain causes a redistribution of charge from the Ba and Cu atoms to the IAEs. Additionally, the biaxial tensile strain induces superconductivity in the BaCu monolayer, and a notable increase in the critical superconducting transition temperature (T
c) to 0.2 K at 10% strain is observed. The coupling between the vibrations of the Cu atoms and IAEs plays a crucial role in this superconductivity. Our findings provide valuable insights into the relationship between the IAEs and superconductivity in the 2D electrides.
Quantum advantages in

(n,d)

↦

1

random access codes
Authors: Ambainis Andris , Kravchenko Dmitry , Sazim Sk , Bae Joonwoo , Rai Ashutosh
Published: December 2024

A random access code (RAC), corresponding to a communication primitive with various applications in quantum information theory, is an instance of a preparation-and-measurement scenario. In this work, we consider (n, d)-RACs constituting an n-length string, constructed from a d size set of letters, and send an encoding of the string in a single d-level physical system and present their quantum advantages. We first characterize optimal classical RACs and prove that a known classical strategy, called majority-encoding-identity-decoding, is optimal. We then construct a quantum protocol by exploiting only two incompatible measurements (the minimal requirement) and show the advantages beyond the classical one. We also discuss the generality of our results and whether quantum advantages are valid for all types of

(
n
,
d
)

↦

1

RACs.
Efficient hardware implementation of ROM-free LFM waveform generation for real-time reconfigurable software-defined radar
Authors: Bellabas A , Mesloub A , Ghezali B , Ziani T , Maali A
Published: December 2024

This paper presents a novel method for generating Linear Frequency Modulation (LFM) waveforms. Conventional Look-Up table (LUT)-based method requires large storage resources, especially in high-resolution, multi-mode radar systems. To address this issue, we propose a ROM-free, real-time LFM waveform generator. It uses the fourth-order Runge-Kutta (RK-4) method to solve differential equations for the in-phase and quadrature components. The proposed approach dynamically generates LFM waveforms using only parameters such as pulse width, bandwidth, and sampling rate, eliminating the need for pre-calculated waveforms and LUTs. This method completely removes storage requirements, enabling faster synthesis times and achieving minimal latency. The generator's performance is validated through simulation and FPGA implementation using a full hardware description language. Results confirm its effectiveness, making it a strong candidate for advanced radar systems that demand high performance with limited hardware resources.
Exploring the dynamics of overtaking interactions of electron acoustic solitons in beam-driven unmagnetized plasmas: application in the auroral region
Authors: Shohaib Muhammad , Masood W , Jahangir R
Published: December 2024

This study explores the propagation of nonlinear electron acoustic waves (EAWs) in an unmagnetized plasma consisting of dynamical inertial cold electrons, hot electrons following (r, q) distribution, a warm electron beam, and background ions. The fluid equations representing the plasma system are reduced to Kadomtsev–Petviashvili (KP) equation for EAWs by using the reductive perturbation technique. Our findings reveal that several key factors significantly influence the propagation and interaction properties of electron acoustic solitary waves (EASWs). These factors include the spectral indices r and q of the generalized (r, q) distribution, the concentrations of cold, hot, and beam electrons, as well as the temperature ratios among these electron populations. Additionally, we investigate the possible types of overtaking interactions between two Kadomtsev–Petviashvili (KP) solitons. The spatial regime for the interaction of two solitons is found to vary depending on the effect of plasma parameters on a single soliton behavior. This comprehensive analysis provides valuable insights into the complex interactions between EASWs, which are relevant for understanding phenomena in laboratory, space, and astrophysical plasmas.
A novel intensity-based phase unwrapping method for highly discontinuous topology
Authors: Yi Jingya , Wei Sheng , Song Mengsa , Tang Yu , Wen Zhiqing , Chen Weilin
Published: December 2024

The analysis of the phase of highly discontinuous surfaces presents significant challenges in the field of fringe projection profilometry. This research proposes a novel phase unwrapping technique based on an illumination attenuation model to efficiently resolve the phase of discontinuous objects. The study begins by analyzing the attenuation characteristics of light intensity with distance. Using the phase height model in the fringe projection profilometry system, the unwrapped light intensity-phase difference distribution map is then computed. A phase mask is subsequently employed to segment discontinuous regions, enabling phase unwrapping within each distinct section. The phase jump order, derived from the light intensity-phase difference, guides the integration of sub-regions to construct the global unwrapped phase map. This method achieves effective phase unwrapping in regions with discontinuities without increasing system complexity or requiring additional projection images. Furthermore, this method is particularly effective for isolated regions exhibiting phase jumps. The effectiveness of the proposed phase unwrapping algorithm is validated through both simulations and experimental evaluations.
Mechanical analysis and function matrix projective synchronization of El-Nino chaotic system
Authors: Shukla Vijay K , Joshi Mahesh C , Mishra Prashant K , Xu Changjin
Published: December 2024

This study explores the mechanical aspects of the El-Nino system by transforming it into a Kolmogorov type system, characterized by four types of torques known as internal, inertial, dissipation, and external. Five scenarios by varying these torques to identify the factors that lead to chaos and their physical significance are also investigated. The interactions between kinetic, potential, and Hamiltonian energies are analyzed and depicted as how these energies interact with system parameters. The study also emphasizes the benefits of conservative chaos over dissipative chaos. Particularly, it has more applications like secure communications and pseudo-random number generation. The role of force interactions and exchanges, including Casimir energy in the generation of chaos is also identified. The transition from regular to irregular orbits, and then to more chaotic states is investigated through Casimir function. It concludes that all four types of torques are necessary to induce chaos in the El Niño chaotic system. Additionally, function matrix projective synchronization between identical El-Nino chaotic systems has achieved.
Bloch sphere representation for Rabi oscillation driven by Rashba field in the two-dimensional harmonic confinement system
Authors: Arai Kaichi , Tojo Tatsuki , Takeda Kyozaburo
Published: December 2024

We studied the dynamical properties of Rabi oscillations driven by an alternating Rashba field applied to a two-dimensional (2D) harmonic confinement system. We solve the time-dependent (TD) Schrödinger equation numerically and rewrite the resulting TD wavefunction onto the Bloch sphere (BS) using two BS parameters of the zenith (θ
B) and azimuthal (ϕ
B) angles, extracting the phase information ϕ
B as well as the mixing ratio θ
B between the two BS-pole states. We employed a two-state rotating wave (TSRW) approach and studied the fundamental features of θ
B and ϕ
B over time. The TSRW approach reveals a triangular wave formation in θ
B. Moreover, at each apex of the triangular wave, the TD wavefunction passes through the BS pole, and the state is completely replaced by the opposite spin state. The TSRW approach also elucidates a linear change in ϕ
B. The slope of ϕ
B vs. time is equal to the difference between the dynamical terms, leading to a confinement potential in the harmonic system. The TSRW approach further demonstrates a jump in the phase difference by π when the wavefunction passes through the BS pole. The alternating Rashba field causes multiple successive Rabi transitions in the 2D harmonic system. We then introduce the effective BS and transform these complicated transitions into an equivalent ‘single’ Rabi one. Consequently, the effective BS parameters

θ

B

eff

and

ϕ

B

eff

exhibit mixing and phase difference between two spin states α and β, leading to a deep understanding of the TD features of multi-Rabi oscillations. Furthermore, the combination of the BS representation with the TSRW approach successfully reveals the dynamical properties of the Rabi oscillation, even beyond the TSRW approximation.
Enhancing entanglement and steering in a hybrid atom–optomechanical system via Duffing nonlinearity
Authors: Dong 董 Ling-Hui 凌晖 , Wu 武 Xiao-Jie 晓捷 , Bai 白 Cheng-Hua 成华 , Wu 武 Shao-Xiong 少雄
Published: December 2024

We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen (EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity, leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system’s resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies.
Interaction between MTM and EGAM for energy and particle confinement improvements on HL-3 tokamak
Authors: Wang S.Q. , Zou X.L. , Duan X.R. , Liang A.S. , Yu L.M. , Xiao G.L. , Zhu Y.R. , Han M.K. , Zhou Y. , Sun T.F. , Wang A. , Gong S.B. , Guo W.P. , Yang Q.L. , Li Y.G. , Wang H.X. , Jiang M. , Zhang Y.P. , Yu D.L. , Shi Z.B. , Chen W. , Zhong W.L. ,   HL-3 Team
Published: December 2024

We report the first observation of microtearing mode (MTM) and its interaction with energetic-particle-induced geodesic acoustic mode (EGAM) in the reduction of ambient turbulence, leading to improvements in energy and particle confinements in electron cyclotron resonance heating (ECRH) plasma on HL-3 tokamak. MTM, observed in the magnetic fluctuation spectrum with a frequency range of 80–120 kHz, is found to be driven by the electron temperature gradient. It has been shown that MTM propagates in the electron diamagnetic drift direction with a poloidal normalized wavenumber

0.05
≤

k
θ

ρ
s

≤
0.17

. The

n
=
0
,

m
=
−
2

magnetic structure of EGAM with a frequency range of 14–20 kHz is observed in the magnetic fluctuation spectrum, where n and m are the toroidal and poloidal mode numbers, respectively. The

V

E
×
B

oscillation of EGAM has also been observed in the Doppler reflectometry phase derivative perturbation spectrum. The frequency of EGAM corresponds to half that of the conventional GAM. Bispectral analysis during ECRH shows pairwise interactions among EGAM, MTM and ambient turbulence (low frequency). It has been found that the reduction of ambient turbulence due to MTM and EGAM leads to the improvement of particle and energy confinements. Experimental results on HL-3 show that the interaction between MTM and EGAM provides a possible way to the turbulence control for energy and particle confinement improvements in future reactors.
A model for analytical calculations of synthetic neutron energy spectra from beam-target reactions
Authors: Valentini A. , Reman B.C.G. , Nocente M. , Eriksson J. , Järleblad H. , Moseev D. , Rud M. , Schmidt B.S. , Snicker A. , Salewski M.
Published: December 2024

We present a fully analytical model for calculating energy spectra of neutrons generated by fusion reactions involving a fast ion, or beam, and a stationary ion, or target, in magnetic fusion plasmas. For neutrons moving along the line-of-sight of a detector, the neutron spectrum is given by an analytical expression and the usual differential cross section. This makes the model several orders of magnitude faster than ordinary Monte Carlo simulations and free of any related statistical noise. Additionally, the analytical description of the reaction physics provides much more insight into the formation of the spectrum. An example of this is the bias of beam-target spectra towards high-energy neutron counts, which corresponds to forward-emission events. On the other hand, the fast-ion uniform gyro-angle distribution has an opposite effect, but is ultimately weaker than the preferential forward emission of neutrons. The model is validated against numerical calculations from the forward model code GENESIS to verify its validity and it is furthermore derived from a probabilistic viewpoint, adding further insight.
Impact of MHD mixed convection on heat and mass transfer in a typical DCLL breeder blanket
Authors: Zhang Wen-Xuan , Zhang Hong-Na , Li Xiao-Bin , Li Feng-Chen
Published: December 2024

A typical dual-coolant lead lithium liquid blanket employs eutectic liquid lithium lead alloy as coolant and tritium breeder for Tokamak nuclear fusion reactor, and is responsible for transporting heat and tritium. The blanket is subjected to both strong magnetic field and strong radially non-uniform neutron volume heating. The flow of liquid metal is influenced by the combined effects of magnetohydrodynamics (MHD), buoyancy, and inertial effects, resulting in a complex MHD mixed convection phenomenon. This study employs direct numerical simulation based on finite volume method to analyze the flow, heat transfer, and mass transfer within blanket unit. The results demonstrate that mixed convection has a significant impact on the MHD pressure drop and flow characteristics. The complex MHD mixed convection gives rise to a considerable number of vortices, particularly in regions of the turn and the downward poloidal duct. The formation of low-speed zones and jets within the blanket has the potential to significantly impact heat and mass transfer, leading to the accumulation of heat and tritium. On the other hand, the markedly elevated tritium production rate is a significant contributing factor to the obviously elevated tritium concentration in the vicinity of the first wall.
Uncertainty quantification analysis using multi-fidelity deep neural network
Authors: Lv Luogeng , Zhao Jiao , Chen Jiangtao
Published: December 2024

In order to solve the highly-dimensional and highly-nonlinear problems in uncertainty quantification of CFD, the paper develops a multi-fidelity neural network model and proposes a residual connection-based multi-fidelity deep neural network fusion model. Based on the small sample size and low computational cost of multi-fidelity models, the residual structure is further utilized to accelerate the convergence rate of the model and reduce the possibility of inducing systemic risks. Finally, the feasibility and accuracy of the algorithm are verified by six typical numerical examples, and the uncertainty quantification analysis of the NACA0012 airfoil’s yaw moment coefficients is completed.
Influence of Axial Flow Field Parameter Fluctuations on Performance of Scramjet Combustor
Authors: Hao Zhang , Mi Yan , Jiahang Li
Published: December 2024

When air-breathing aircraft is flying over a wide area, the upflow of the combustor central axis will change greatly, and the flow field parameters will fluctuate along the axis. Therefore, it is necessary to carry out a study on the influence of axis flow field parameter fluctuation on combustion chamber performance, so as to provide relevant theoretical support for the combustion chamber of air-breathing aircraft in wide-area flight design. Based on the N-S gas-phase control model, combined with combustion model, turbulence model, burning rate model and mass transfer model, a numerical simulation model of flow combustion in solid fuel scramjet combustor is established. Through this model, the influence of the upflow field parameter fluctuation of the central axis on the combustor performance is carried out. The results show that for a optimized combustor configuration, different inlet air flow rates will cause the Mach number of the combustor to oscillate along the flow direction. The greater the oscillation amplitude, the greater the total pressure loss. Too high or too low inlet air flow rate will both result in Mach number oscillation in the combustor. However, selecting a suitable inlet air flow rate can significantly reduce the Mach number oscillation of combustor flow. Therefore, for different combustor configurations, appropriate inlet air flow should be designed to reduce the Mach number oscillation of the flow field in the combustor, reducing the flow loss and improving the working performance of the combustor.
Numerical Investigation of Pressure Measurement by Pitot Tubes in Micro-scale Taylor Couette Flow with Hyper Rotational Speed and its Correction
Authors: Yuan Wenduo , Chen Kunxiang , Huang Ying , Lyu Yuan-wei
Published: December 2024

As the most classic technique in fluid mechanics, the pitot tube has been employed for hundreds of years. Its feasibility is based on the premise that the measured fluid is ideal, irrotational, and incompressible, and the presence of pitot tube does not interfere with the measured flow field. However, the development of rotating machinery, especially Dynamic Gas Bearing, has brought about strong dissipation, large gradients, and scale effects in the shear flow between the rotor and stator, which urgently require pressure correction as conventional pitot tube has been utilized. The physical mechanism of the influence of the existence of pitot tubes on micro-scale shear flow has been revealed. The cavity formed by the pitot tubes interferes with the shear flow in the transition static gap, causing instability in the shear flow. Compared to the absence of a pitot tube, the pitot tube has brought 3.5% -10% of underprediction of mean pressure. the effects of rotational speed, clearance has been performed in microscale hyper-rotational speed shearing flow. A pressure correction method using the pitot tube pressure was presented for strong dissipation, large gradients, and scale effects, verifying its effectiveness in microscale hyper-rotational speed Taylor Coulter flow.
Analysis of Crack Control Effect in Reinforced Concrete T-Beams Strengthened with External Prestressing
Authors: Shen Tianjiao , Fan Ping , Dong Jun
Published: December 2024

For urban bridges experiencing insufficient load-bearing capacity, external prestressing is a commonly adopted strengthening method. This study focuses on the crack control of reinforced concrete T-beams strengthened using external prestressing, using the Jiude Road Shengli Channel Bridge as a case study. By conducting static load tests on two main beams, we compared the strengthening effects. The results demonstrate that the method of strengthening reinforced concrete T-beams with external prestressing effectively controls the cracks in the main beams.
CFD simulation and Grid study of Flying Wing Standard Model
Authors: Shen Yingying , Cui Pengcheng , Chen Hongyang , Xiao Wei , Hu Xiangpeng , Zhao Jiao , Lv Luogeng , Zhao Wei
Published: December 2024

In order to study the influence of mesh size variation on the numerical simulation of typical flying wing model, based on the verification and validation of NNW-FlowStar software, the numerical simulation of flying wing model with multiple sets of unstructured grids with succession variation in Ma=0.9 is carried out, and the lift coefficient, drag coefficient and pitching moment coefficient under corresponding conditions are obtained. Results show that as the height of the first layer decreases, lift coefficient is gradually approaching converged. When the height of the first layer reaches 0.04, the simulation error is already within 1%.
Comparison of different self-assembly methods for formation of a homogenous monolayer of polystyrene
Authors: Modrić-Šahbazović A , Gazdić I , Smajlagić A , Karić E , Babajić L , Dedić L
Published: December 2024

In this paper, we report on the formation of nanomasks by polystirene (PS) spheres as small as 150 nm in diameter using different self-assembly methods. Spin coating method was the most efficient. The influence of spin speeds, spinning time, solution quantity is studied in order to achieve a large area close-packed monolayer. A relatively high surface coverage and uniform monolayer of PS spheres can be achieved by appropriate control of the preparative parameters. It can be useful in industrial applications, because of the fabrication speed, surface coverage, control over PS spheres and cost of the process.
Static measurement of magnetic hysteresis loop for spring steel and vacon 11 (metal-ceramic alloy NiFeCo) materials
Authors: Dupljanin Snježana , Čeliković Mirko , Mirjanić Dragoljub
Published: December 2024

The paper presents the results of magnetic hysteresis measurements for the materials spring steel and metal-ceramic alloy NiFeCo (Vacon 11). A static measurement was performed over a wide range of the external field H, from -10000 to 10000 A/m for the first material and from -12600 to 12600 A/m for the second. The B-H curve, also known as the hysteresis loop was created. Based on this curve, it was determined that both materials belong to the group of magnetically semi-hard materials, with coercivity ranging from 1000 to 50000 A/m. The measurement results were compared to the theoretical predictions of the analytical Fro hlich`s model, which indicated certain deviations from the measured values, with the largest deviation being 25.53%.
Identifying parameters impacting WASH STEM education across the globe
Authors: Orebiyi Mark Adebamibo , Moore Laura , Jones Stephen , Smith Virginia
Published: December 2024

This study seeks to assess the parameters impacting successful water, sanitation and hygiene (WASH) science, technology, engineering, and math (STEM) educational outreach. Previous studies have shown a correlation between underprivileged communities and significant impacts due to water related disasters, such as flooding or water related illnesses. As a result, for several decades the international development community has invested in WASH-related infrastructure. Lessons learned through these investments has shown the need for WASH educational outreach to build community awareness and encourage behavioral change, ultimately ensuring the sustainability and impact of the WASH infrastructure. Many WASH infrastructure programs have incorporated WASH education programs, particularly those led by the community. Often this occurs through primary and secondary schools. While WASH STEM education promotes local project ownership, leading to an increased understanding of water management and infrastructure resiliency, these educational programs are not always successful. There is a knowledge gap in understanding what makes WASH STEM education and outreach effective. This research project investigated some of the parameters influencing students’ performance on an assessment of WASH STEM curricula. This was done through deploying two water resource learning modules and assessments to secondary school students in Cambodia, India, Nicaragua, and the United States. The results revealed a correlation between how well the students comprehended the information according to the assessment and how relevant the students found the material to their own lives. The insight gained from this study can create more impactful WASH STEM education and outreach programs for water resource projects, and beyond.
Upgrading of low-grade iron using alkaline roasting
Authors: Faesal A , Naderajan L , Ishak K E H K
Published: December 2024

The characterization and upgrading of low-grade iron ore from Sungai Petani, Kedah, face significant challenges due to the presence of gangue minerals such as silica (Si), alumina (Al), and phosphorus (P). This study aims to address these challenges by comparing the effectiveness of alkali roasting and conventional roasting methods in enhancing the iron content of the ore. The iron ore samples, derived from the Sungai Petani region, were analyzed to determine their mineralogical and chemical characteristics. Alkali roasting and conventional roasting were implemented as pretreatment techniques. The results demonstrated that alkali roasting was significantly more effective than traditional roasting in upgrading the low-grade iron ore by facilitating the transformation of goethite into hematite, resulting in lower porosity and reduced gangue content.
Leaching of rare earth elements from Malaysian monazite: effect of dephosphorization
Authors: Erintina M D , Yunus A I Md , Mohamed A Z , Paulus W , Ismail S
Published: December 2024

Phosphates interfere the leaching process and raise environmental concerns when it comes to the extraction of rare earth elements (REEs) from monazite. This study investigates the dephosphorization behaviour of Malaysian monazite through a statistical design of experiments approach, focusing on the variables of baking reagents, roasting time, and temperature. The raw monazite sample was characterized using X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses, revealing the presence of phosphorus (P), rare earth elements (REEs) including cerium (Ce) and lanthanum (La), thorium (Th), and trace elements such as sodium (Na), iron (Fe), silicon (Si), and magnesium (Mg). The XRD analysis confirmed the dominance of CePO4 and LaPO4 phases in the monazite sample. The dephosphorization process was optimized, with the highest rare earth elements recovery achieved at 250°C for 4 hours using potassium hydroxide (KOH) as the baking reagent. In addition, the sample with the lowest concentration of phosphorus leached 84.1% of the rare earth elements. It indicates that a high level of phosphorus removal can lead to a significant recovery of rare earth elements (REEs) and provides significant information for environmentally friendly REE extraction practices.
Utilization of Gamma & Weibull Distribution Functions in Validating Experimental-based Result of Ore Amenability for Coarse Gangue Rejection
Authors: Aslam I N , Ayuni R , Albijanic B , McGrath T
Published: December 2024

The mining industry faces two-pronged challenges, that is the increasing demand for commodities and declining ore quality, resulting in higher energy consumption and operational costs but poor productivity. Multiple methods have been proposed to address this issue, including early coarse gangue rejection which requires further amenability testing by either experiments and statistical analysis. Experimental approaches, such as Gangue Rejection Amenability Tests (GRAT), have demonstrated efficacy but required substantial time and resources. Statistical methodologies utilizing lognormal distributions offered an alternative, but unable to validate statistical outcomes against experimental results. This study investigated the potential of alternative statistical methods (i.e., gamma and Weibull distributions) to validate GRAT. Through the analysis of grade and density parameters data drawn from eight ore fractions, this research constructed an accurate statistical model for predicting ore separation results. The model’s accuracy was evaluated based on coefficient of determination, heterogeneity of data, and comparison of statistical predictions of cumulative mass and metal yield with laboratory results. The results of employing two distributions did not yield accurate predictions of GRAT results. The statistical values tended to be higher than the experimental results for both parameters. We suggested that alternative functions be tested for more representative and suitable use in coarse gangue rejection applications.
VME-EFD : A novel framework to eliminate the Electrooculogram artifact from single-channel EEGs
Authors: Noorbasha Sayedu Khasim , kumar Arun
Published: December 2024

The diagnosis of neurological disorders often involves analyzing EEG data, which can be contaminated by artifacts from eye movements or blinking (EOG). To improve the accuracy of EEG-based analysis, we propose a novel framework, VME-EFD, which combines Variational Mode Extraction (VME) and Empirical Fourier Decomposition (EFD) for effective EOG artifact removal. In this approach, the EEG signal is first decomposed by VME into two segments: the desired EEG signal and the EOG artifact. The EOG component is further processed by EFD, where decomposition levels are analyzed based on energy and skewness. The level with the highest energy and skewness, corresponding to the artifact, is discarded, while the remaining levels are reintegrated with the desired EEG. Simulations on both synthetic and real EEG datasets demonstrate that VME-EFD outperforms existing methods, with lower RRMSE (0.1358 versus 0.1557, 0.1823, 0.2079, 0.2748), lower ΔPSD in the α band (0.10 ± 0.01 and 0.17 ± 0.04 versus 0.89 ± 0.91 and 0.22 ± 0.19, 1.32 ± 0.23 and 1.10 ± 0.07, 2.86 ± 1.30 and 1.19 ± 0.07, 3.96 ± 0.56 and 2.42 ± 2.48), and higher correlation coefficient (CC: 0.9732 versus 0.9695, 0.9514, 0.8994, 0.8730). The framework effectively removes EOG artifacts and preserves critical EEG features, particularly in the α band, making it highly suitable for brain-computer interface (BCI) applications.
Evading the intermediate temperature brittleness of a precipitation-strengthened CoNiCr alloy by grain boundary engineering
Authors: Zhang Zhouqing , Ding Qingqing , Gao Yanfei , Wei Xiao , Zhang Ze , Bei Hongbin
Published: December 2024

Intermediate temperature brittleness in alloys characterized as brittle fracture along grain boundaries (GBs) with less than 5% elongation to fracture (EF) at 600 °C–900 °C diminishes work hardening, leads to sudden failure under load, and thus threatens the reliability during the service of alloys. Here, in a precipitation-strengthened CoNiCr alloy, through two grain boundary engineering (GBE) methods, fiber-like γ′ or topologically close-packed phase is introduced at GBs, which effectively optimizes the grain structure and prevents GB cracking under tensile stresses. GBEs not only alter the deformation mode from dislocation pairs to stacking faults and/or deformation twins, but also transform the failure mode from GB cracking to GB void formation, because the crack propagation along GBs is constrained by GB bridging phases. Consequently, our GBE approach enhances tensile EF from ∼1% to ∼10% and concurrently increases the yield strength from ∼650 to ∼770–850 MPa at 800 °C. A cavity growth model is then developed to illustrate the role of these bridging phases in GBs for ductility improvement. The fundamental philosophy utilized in the present work might be also applicable to other metallic materials.
Uniform L1 error estimates for the semidiscrete finite element solutions of a parabolic integro-differential equation
Authors: Xu Da
Published: December 2024

We analyze the semidiscrete piecewise linear finite element methods for parabolic integro-differential equations with some nonempty spectral sets that arise in the modeling of viscoelasticity fluid in porous media. The long time error estimates are obtained with smooth initial data. More precisely, by introducing piecewise linear finite element residual resolvent solution and its spectral resolution we derive optimal order $ L^{1}(0,\infty ;L^{2}(\varOmega )) $ error estimates with smooth initial data. Numerical experiments confirm the convergence rates of the proposed estimates.
Examining Psychosis Risk in Sexual Minority Youth: Increased Exposure to and Differential Impact of the Social Envirome in Early Adolescence
Authors: Sageot Margaux , Myin-Germeys Inez , Achterhof Robin , van Winkel Ruud
Published: December 2024

Background and Hypotheses

Sexual minority populations have a higher prevalence of psychotic experiences (PE), possibly due to differential experiences within the social envirome in its positive (eg, social support, parenting) and negative aspects (eg, adverse life events, bullying). This study hypothesized that (1) sexual minority adolescents experience more PE, (2) are more exposed to harmful aspects of the social envirome, and (3) may display differential sensitivity to certain aspects of the social envirome.

Study Design

Data from 678 adolescents (mean age 15.6 years) were analyzed. Psychotic experiences were assessed using the Prodromal Questionnaire 16 (PQ-16). Aspects of the social envirome (childhood adversity, bullying, parenting style, and social support) were evaluated using different questionnaires.

Study Results

The odds ratio of having sexual minority status (SMS) was 1.98 (95 CI%, 1.02–3.84) for participants with PE (PQ-16 ≥ 6) compared to participants without. Significant associations were found between SMS and more adverse childhood experiences (95% CI, 0.11–3.51) and parenting psychological control (95% CI, 0.11–0.53), and less parenting autonomy support (95% CI, −0.37 to −0.01). There were also significant differential effects: adverse childhood experiences were associated with PE in heterosexuals but not in sexual minorities (95% CI, −0.34 to −0.03), while less social support was associated with more PE in heterosexuals but less PE in sexual minorities (95% CI, 0.06–0.39).

Conclusions

Sexual minority status is associated with a higher prevalence of PE, greater exposure to harmful factors within the social envirome, and differential effects on sexual minority and heterosexual individuals. These results emphasize the need for a fine-grained analysis of the envirome to understand the increased risk for PE in sexual minorities.
Comparison Between in Situ Fixation and Fixation After Closed Reduction in Valgus-Impacted Femoral Neck Fractures: A Multicenter Study
Authors: Jang Byung-Woong , Park Jung-Wee , Nho Jae-Hwi , Kim Jinjae , Kim Tae-Young , Lee Young-Kyun , Kim Jin-Woo
Published: December 2024

OBJECTIVES:

The objective of this study was to compare clinical outcomes between in situ fixation and fixation after closed reduction (CR) in patients aged 50 years and older with valgus-impacted femoral neck fractures using data from multiple centers.

METHODS:

Design:

Retrospective multicenter cohort study.

Setting:

Five tertiary-care university hospitals.

Patient Selection Criteria:

Patients aged 50 years and older, treated with operative fixation of valgus-impacted femoral neck fractures using multiple cannulated screws from 2003 to 2019.

Outcome Measures and Comparisons:

Complications such as fixation failure, osteonecrosis of femoral head (ONFH), and reoperation were compared between the groups (in situ fixation group and fixation after CR group). Postoperative EuroQol-5 Dimension (EQ-5D), Harris Hip Score, and Koval grade were compared.

RESULTS:

The mean age of the 206 patients (161 in situ fixation group, 45 in fixation after CR group) who met the inclusion criteria was 68.9 ± 10.9 years (range, 50–95 years). There were 39 men and 167 women. Fixation failure occurred in 11.2% (6.8% of in situ fixation group vs. 26.7% of fixation after CR group, P = 0.002). Reoperation was required for 10.2% (7.5% of the in situ fixation group vs. 20% of the fixation after CR group, P = 0.023). Fixation failure and reoperation rates were significantly higher in the fixation after the CR group than in the in-situ fixation group (odds ratio = 4.757, P = 0.002 and odds ratio = 3.104, P = 0.023, respectively). At the 2-year follow-up, ONFH occurred in 5.8% (9 out of 161, in situ fixation group vs. 3 out of 45, fixation after CR group). There was no significant difference in the occurrence of ONFH between the 2 groups (P = 0.727). The Koval's grade at 6 and 12 months demonstrated better results in the in-situ group (P = 0.027, 0.044, respectively). Postoperative EQ-5D and Harris Hip Score scores showed no statistically significant differences between the 2 groups.

CONCLUSIONS:

In patients aged 50 years or older with valgus-impacted femoral neck fractures, when fixation was done after reduction, the reoperation rate was higher due to fixation failure compared with in-situ fixation. There was no significant difference in the incidence of ONFH in valgus-impacted femoral neck fractures regardless of whether reduction was performed.

LEVEL OF EVIDENCE:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Nonunion of Adult Forearm Fractures: Evaluation of Intramedullary Nailing With Grafting as a Treatment Option
Authors: Onay Tolga , Akkaya Mesut , Dilek Mehmet , Tütüncü Mehmed Nuri , Akpınar Fuat
Published: December 2024

OBJECTIVES:

To evaluate the effectiveness of intramedullary nailing combining with iliac or fibular autograft for the treatment of adult forearm nonunions.

METHODS:

Design:

Retrospective case series.

Setting:

Two academic trauma referral centers.

Patient Selection Criteria:

Adult patients who sustained surgical treatment for forearm fracture (OTA/AO 2R2-2U2) nonunion with intramedullary nailing and grafting from May 2005 to January 2023 were included.

Outcome Measures and Comparisons:

The primary outcome was to determine the bone union rates after nonunion surgery with intramedullary nail and grafting. Secondary outcomes were to assess functional scores including The Visual Analog Score; the shortened version of the Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire; Grace–Eversmann evaluation criteria.

RESULTS:

The study included 24 patients comprising 19 men and 5 women (7 radius, 14 ulna, 3 both bones) with an average age at the time of surgery of 40.5 ± 11.2 years (range, 23–61 years) and union was achieved for 24 out of 27 bones (88.8%) in 22 out of 24 patients. The mean (average) preoperative and postoperative QuickDASH scores were found as 64.5 ± 18.2 and 15.3 ± 18.9, respectively. The functional improvement was found statistically significant (P < 0.001). The mean (average) preoperative and postoperative Visual Analog Score was found to be 7.2 ± 2.1 and 1.52 ± 1.5, respectively. The difference was found statistically significant (P < 0.001). Two cases of radius nonunion healed with 10 degrees and 15 degrees of angulation and shortening, while nonunion persisted in 2 patients. All remaining cases healed without deformity. Excellent to acceptable results were obtained for 83.3% of patients according to Grace–Eversmann criteria.

CONCLUSİONS:

Intramedullary nailing with autologous grafting is a viable option for the treatment of adult forearm nonunions.

LEVEL OF EVIDENCE:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Diversifying the Nursing Workforce Through Holistic Admissions Review to Nursing School
Authors: Fangonil-Gagalang Evangeline
Published: December 2024

Although a diverse healthcare workforce has been linked to improved care quality and cost savings, the U.S. nursing workforce does not mirror the population of underrepresented minority (URM) groups in the country. Holistic admissions review (HAR) is an innovative process that can increase the number of URM students entering nursing education programs. In addition to using traditional grade point average and entrance test scores for admissions criteria, HAR considers non-academic attributes such as personal qualities and life experiences. Nursing schools that adopt HAR can help diversify the nursing workforce. Lebacqz's (1987) Six Theories of Justice can aid Christian nurse educators in evaluating and advocating for HAR.
Integrating Faith and Learning Using a Biblical Concept-Based Curriculum
Authors: Bell Ashley
Published: December 2024

The integration of faith and learning (IFL) in nursing has deep historical roots. However, barriers have developed to successful IFL in Christian higher education. A biblically based concept curriculum (BBCC) is proposed that emphasizes deep learning, critical thinking, and student-centered learning. Examples are provided of BBCC curricular integration, pedagogical methods, and assessments related to the IFL. Results of student evaluations before and after implementation of the BBCC identified an increase in students' perceptions of IFL in nursing courses.
Orgasmic Disorders
Authors: Giraldi Annamaria
Published: December 2024

Aim:

To describe orgasm disorders in women.

Results:

Orgasmic problems are prevalent in women, and many experience distress related to the condition. The problem often co-exist with other sexual disorders and can be caused by many biopsychocial factors. A comprehensive assessment focusing on biopsychosocial factors contributing to the orgasmic problem is necessary. This includes a sexological, medical, and psychological history. Treatment should include cognitive and behavioral interventions, which may include the partner. No pharmacological treatment is approved to treat orgasmic disorders in women.
Residual silicone oil does appear after conventional removal and contributes to postoperative emulsification
Authors: Chen Ying , Wang Li Kenneth Kai , Steel David H , Chan Yau Kei
Published: December 2024

Purpose:

To validate the presence of residual non-emulsified silicone oil (SO) following conventional surgical removal techniques used in vitreoretinal surgery and provide insights for optimizing surgical parameters and reducing subsequent emulsification-related complications.

Methods:

The two surgical steps of repeated fluid-air exchange (FAX), including aspiration and infusion, were simulated in vitro to investigate their effectiveness in removing residual non-emulsified SO under various clinical settings. Aspiration was performed at three different positions with respect to the SO interface (i.e., within the SO phase, at the SO/BSS interface, and within the BSS phase) with a 25-gauge probe. An infusion was positioned near the SO/BSS interface with an intraoperatively standardized flow rate (5mL/min). In a further ex vivo study, the volume of residual non-emulsified SO (collected by Dichloromethane) was quantified by Flourier-transform infrared spectroscopy (FTIR) in both repeated FAX and passive drainage (PD) groups.

Results:

In the in vitro model, regardless of which position a 25-gauge probe was located, residual non-emulsified SO could not be effectively removed even under high aspiration levels (p>0.05). Continuous BSS infusion led to small SO droplet formation. Residual SO in both non-emulsified and emulsified forms was observed in the ex-vivo model subjected to repeated FAX. The volume of residual non-emulsified SO was quantified, ranging from 2.75 to 24.71 μL, without significant difference among experimental groups (p>0.05).

Conclusions:

Complete residual non-emulsified SO removal was technically challenging by conventional surgical techniques. This residual non-emulsified SO could serve as a source of ongoing SO emulsification.