bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical switch model of novel asymmetric magnetorheological damper for shock and vibration application
Authors: Liang Huijun , Fu Jie , Li Wei , Wang Yongsheng , Luo Lei , Qi Song , Yu Miao 
Published: November 2023

Abstract
This study proposed a novel asymmetric conical flow channel magnetorheological damper (CFC-MRD) for all-terrain vehicles (ATVs) to handle complex excitations with coexisting shocks and vibrations. CFC-MRD produces adjustable damping forces by utilizing magnetically controlled properties and achieves asymmetric force output (moderate compression force and strong extension force) with conical flow channels. This design could effectively absorb and dissipate energy. The paper first illustrates the structure and asymmetric principle of CFC-MRD. Then, the mechanism of asymmetric force generation in a non-parallel flat plate is derived, and utilizes the hydrodynamic theory to derive the pressure difference of Bingham fluid between the non-parallel plates. Considering the coexistence of vibration and shock, the study proposes a theoretical switch model that distinguishes between low and high velocity states based on the Reynolds number. Finally, the validity of the model is verified by experiments, and the results show that the CFC-MRD achieves the desired asymmetric force output. The asymmetric force ratio rises with higher excitation speed and drops with increased drive current. At a speed of 1 m s−1 without any applied current, the maximum asymmetric force reaches 1.21. The small peak error, averaging only 2.57%, between experimental and theoretical results affirms the accuracy of the proposed switch model.
Higher-order random network models
Authors: Huang Jinyu , Hu Youxin , Li Weifu , Lin Maoyan 
Published: November 2023

Abstract
Most existing random network models that describe complex systems in nature and society are developed through connections that indicate a binary relationship between two nodes. However, real-world networks are so complicated that we can only identify many critical hidden structural properties through higher-order structures such as network motifs. Here we propose a framework in which we define higher-order stubs, higher-order degrees, and generating functions for developing higher-order complex network models. Then we develop higher-order random networks with arbitrary higher-order degree distributions. The developed higher-order random networks share critical structural properties with real-world networks, but traditional connection-based random networks fail to exhibit these structural properties. For example, as opposed to connection-based random network models, the proposed higher-order random network models can generate networks with power-law higher-order degree distributions, right-skewed degree distributions, and high average clustering coefficients simultaneously. These properties are also observed on the Internet, the Amazon product co-purchasing network, and collaboration networks. Thus, the proposed higher-order random networks are necessary supplements to traditional connection-based random networks.
Thermodynamics of deterministic finite automata operating locally and periodically
Authors: Ouldridge Thomas E , Wolpert David H 
Published: November 2023

Abstract
Real-world computers have operational constraints that cause nonzero entropy production (EP). In particular, almost all real-world computers are ‘periodic’, iteratively undergoing the same physical process; and ‘local’, in that subsystems evolve whilst physically decoupled from the rest of the computer. These constraints are so universal because decomposing a complex computation into small, iterative calculations is what makes computers so powerful. We first derive the nonzero EP caused by the locality and periodicity constraints for deterministic finite automata (DFA), a foundational system of computer science theory. We then relate this minimal EP to the computational characteristics of the DFA. We thus divide the languages recognised by DFA into two classes: those that can be recognised with zero EP, and those that necessarily have non-zero EP. We also demonstrate the thermodynamic advantages of implementing a DFA with a physical process that is agnostic about the inputs that it processes.
Potential-tuned magnetic switches and half-metallicity transition in zigzag graphene nanoribbons
Authors: Li Weijian , Xiao Shi-Chang , Sun Da-Fei , Gong Chang-De , Yu Shun-Li , Zhou Yuan 
Published: November 2023

Abstract
Realizing controllable room-temperature ferromagnetism in carbon-based materials is one of recent prospects. The magnetism in graphene nanostructures reported previously is mostly localized by breaking the local sublattice imbalance. Here, we predict a robustly potential-tuned ferromagnetic domain lying between the inter-chain carbon atoms inside the zigzag graphene nanoribbons. We show that the effective zigzag edges provide the strong correlation background through narrowing the band width, while the internal Van Hove filling (VHF) provides the strong ferromagnetic background inherited from the bulk. The induced ferromagnetism exhibit interesting switching effect when the nominal VHF crosses the intra- and inter-chain region by tuning the potential drops. We further observe a robust half-metallicity transition from one spin channel to another within the same magnetic phase. These novel properties provide promising ways to manipulate the spin degree of freedom in graphene nanostructures.
Multichromatic supercontinuum polarization shaping applied to photoelectron holography
Authors: Köhnke D , Eickhoff K , Bayer T , Wollenhaupt M 
Published: November 2023

Abstract
We present a supercontinuum pulse shaping method specifically designed for the generation of polarization-tailored multichromatic femtosecond laser fields. By combining a 4f-polarization pulse shaper with a custom-made polarizer kit, we independently modulate different spectral bands of a white-light supercontinuum in amplitude, phase, and polarization. The scheme is highly modular, scalable to any number of bands supported by the input spectrum and aims at the physically motivated design of specific laser fields tailored to the relevant transitions and dynamics of the quantum system. The power and versatility of the scheme is showcased in three different scenarios based on atomic multiphoton ionization employing polarization-tailored trichromatic pulse sequences. (1) We demonstrate the creation of an

f

x
(

x
2

−
3

y
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-type free electron wave packet and reconstruct its 3D momentum distribution by a waveplate-free shaper-based photoelectron tomography technique. (2) We utilize the holographic properties of the wave packet to study time-resolved and phase-sensitive ultrafast dynamics of bound states. (3) We investigate the field-free time-evolution of a photoelectron wave packet in the continuum. Our results on an atomic model system demonstrate the great potential of the modular shaping scheme for a wide range of applications on more complex quantum systems, including polyatomic molecules, nanoscopic structures and solids.
Constraints on the rotating self-dual black hole with quasi-periodic oscillations
Authors: Liu Cheng , Siew Hoongwah , Zhu Tao , Wu Qiang , Sun Yi , Zhao Yuanyuan , Xu Haiguang 
Published: November 2023

Abstract
An impressive feature of loop quantum gravity (LQG) is that it can elegantly resolve both the big bang and black hole singularities. By using the Newman-Janis algorithm, a regular and effective rotating self-dual black hole (SDBH) metric could be constructed, which alters the Kerr geometry with a polymeric function P from the quantum effects of LQG geometry. In this paper, we investigate its impact on the frequency characteristics of the X-ray quasi-periodic oscillations (QPOs) from 5 X-ray binaries and contrast it with the existing results of the orbital, periastron precession and nodal precession frequencies within the relativistic precession model. We apply a Monte Carlo Markov Chain (MCMC) simulation to examine the possible LQG effects on the X-ray QPOs. We found that the best constraint result for the rotating self-dual geometry from LQG came from the QPOs of X-ray binary GRO J1655-40, which establish an upper bound on the polymeric function P less than 6.15 × 10-3 at 95% confidence level.
This bound leads to a restriction on the polymeric parameter δ of LQG to be 0.66.
Neutrinos from GRB 221009A: producing ALPs and explaining LHAASO anomalous γ event
Authors: Bernal Nicolás , Farzan Yasaman , Smirnov Alexei Yu. 
Published: November 2023

Abstract
We propose a novel explanation for the 18 TeV gamma ray from GRB 221009A observed by LHAASO. High-energy neutrinos are converted into axion-like particles (ALPs) via their interaction with the cosmic neutrino background. Subsequently, ALPs are converted into high-energy photons in the magnetic field of our galaxy. We compute the fluxes of neutrinos, ALPs, and photons reaching Earth. IceCube's constraints on the neutrino flux from GRB 221009A translate into a severe upper bound on the photon flux. We find a range of parameters where all existing bounds are satisfied and the 18 TeV LHAASO photon can be explained. In the future, the specific correlation between the photon and neutrino flux reaching Earth from powerful neutrino sources with energies larger than 10 TeV such as GRBs or AGNs, can be used as a tool to differentiate our explanation from the alternatives suggested in the literature. We discuss how the interactions of our scenario can be embedded within electroweak gauge-invariant models, avoiding various cosmological and terrestrial bounds. We comment on the possibility of explaining the 251 TeV photon observed by the Carpet-2 detector, taking into account the bounds from the observation of high-energy neutrinos from TXS 0506+056.
Using oscillatory and aperiodic neural activity features for identifying idle state in SSVEP-based BCIs reduces false triggers
Authors: Wang Rui , Zhou Tianyi , Li Zheng , Zhao Jing , Li Xiaoli 
Published: November 2023

Abstract

Objective. In existing studies, rhythmic (oscillatory) components were used as main features to identify brain states, such as control and idle states, while non-rhythmic (aperiodic) components were ignored. Recent studies have shown that aperiodic (1/f) activity is functionally related to cognitive processes. It is not clear if aperiodic activity can distinguish brain states in asynchronous brain–computer interfaces (BCIs) to reduce false triggers. In this paper, we propose an asynchronous method based on the fusion of oscillatory and aperiodic features for steady-state visual evoked potential-based BCIs. Approach. The proposed method first evaluates the oscillatory and aperiodic components of control and idle states using irregular-resampling auto-spectral analysis. Oscillatory features are then extracted using the spectral power of fundamental, second-harmonic, and third-harmonic frequencies of the oscillatory component, and aperiodic features are extracted using the slope and intercept of the first-order polynomial of the spectral fit of the aperiodic component under a log-logarithmic axis. The process produces two types of feature pools (oscillatory, aperiodic features). Next, feature selection (dimensionality reduction) is applied to the feature pools by Bonferroni corrected p-values from two-way analysis of variance. Last, these spatial-specific statistically significant features are used as input for classification to identify the idle state. Main
results. On a 7-target dataset from 15 subjects, the mix of oscillatory and aperiodic features achieved an average accuracy of 88.39% compared to 83.53% when using oscillatory features alone (4.86% improvement). The results demonstrated that the proposed idle state recognition method achieved enhanced performance by incorporating aperiodic features. Significance. Our results demonstrated that (1) aperiodic features were effective in recognizing idle states and (2) fusing features of oscillatory and aperiodic components enhanced classification performance by 4.86% compared to oscillatory features alone.
Concurrent and continuous estimation of multi-finger forces by synergy mapping and reconstruction: a pilot study
Authors: Teng Zhicheng , Xu Guanghua , Zhang Xun , Chen Xiaobi , Zhang Sicong , Huang Hsien-Yung 
Published: November 2023

Abstract

Objective. The absence of intuitive control in present myoelectric interfaces makes it a challenge for users to communicate with assistive devices efficiently in real-world conditions. This study aims to tackle this difficulty by incorporating neurophysiological entities, namely muscle and force synergies, onto multi-finger force estimation to allow intuitive myoelectric control. Approach. Eleven healthy subjects performed six isometric grasping tasks at three muscle contraction levels. The exerted fingertip forces were collected concurrently with the surface electromyographic (sEMG) signals from six extrinsic and intrinsic muscles of hand. Muscle synergies were then extracted from recorded sEMG signals, while force synergies were identified from measured force data. Afterwards, a linear regressor was trained to associate the two types of synergies. This would allow us to predict multi-finger forces simply by multiplying the activation signals derived from muscle synergies with the weighting matrix of initially identified force synergies. To mitigate the false activation of unintended fingers, the force predictions were finally corrected by a finger state recognition procedure. Main results. We found that five muscle synergies and four force synergies are able to make a tradeoff between the computation load and the prediction accuracy for the proposed model; When trained and tested on all six grasping tasks, our method (SYN-II) achieved better performance (R
2 = 0.80 ± 0.04, NRMSE = 0.19 ± 0.01) than conventional sEMG amplitude-based method; Interestingly, SYN-II performed better than all other methods when tested on two unknown tasks outside the four training tasks (R
2 = 0.74 ± 0.03, NRMSE = 0.22 ± 0.02), which indicated better generalization ability. Significance. This study shows the first attempt to link between muscle and force synergies to allow concurrent and continuous estimation of multi-finger forces from sEMG. The proposed approach may lay the foundation for high-performance myoelectric interfaces that allow users to control robotic hands in a more natural and intuitive manner.
The direct and indirect effects of the environmental factors on global terrestrial gross primary productivity over the past four decades
Authors: Chen Yue , Zhu Zaichun , Zhao Weiqing , Li Muyi , Cao Sen , Zheng Yaoyao , Tian Feng , Myneni Ranga B 
Published: November 2023

Abstract
Gross primary productivity (GPP) is jointly controlled by the structural and physiological properties of the vegetation canopy and the changing environment. Recent studies showed notable changes in global GPP during recent decades and attributed it to dramatic environmental changes. Environmental changes can affect GPP by altering not only the biogeochemical characteristics of the photosynthesis system (direct effects) but also the structure of the vegetation canopy (indirect effects). However, comprehensively quantifying the multi-pathway effects of environmental change on GPP is currently challenging. We proposed a framework to analyse the changes in global GPP by combining a nested machine-learning model and a theoretical photosynthesis model. We quantified the direct and indirect effects of changes in key environmental factors (atmospheric CO2 concentration, temperature, solar radiation, vapour pressure deficit (VPD), and soil moisture (SM)) on global GPP from 1982 to 2020. The results showed that direct and indirect absolute contributions of environmental changes on global GPP were 0.2819 Pg C yr−2 and 0.1078 Pg C yr−2. Direct and indirect effects for single environmental factors accounted for 1.36%–51.96% and 0.56%–18.37% of the total environmental effect. Among the direct effects, the positive contribution of elevated CO2 concentration on GPP was the highest; and warming-induced GPP increase counteracted the negative effects. There was also a notable indirect effect, mainly through the influence of the leaf area index. In particular, the rising VPD and declining SM negatively impacted GPP more through the indirect pathway rather than the direct pathway, but not sufficient to offset the boost of warming over the past four decades. We provide new insights for understanding the effects of environmental changes on vegetation photosynthesis, which could help modelling and projection of the global carbon cycle in the context of dramatic global environmental change.
A rare case of Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis mimicking a flare of Systemic Lupus Erythematosus in a middle-aged man: A Case Report
Authors: Omo-Ogboi A C , Shirai S , Buja M , Ederhion J 
Published: November 2023

Abstract

Introduction/Objective
Disseminated histoplasmosis is a progressive granulomatous disease caused by Histoplasmosis capsulatum which is an intracellular dimorphic fungus endemic to Ohio and Mississippi River valleys in the United States. The progressive spread of the infection to organs is thought to be due to the failure of the activation of the T-cell mediated immune response. Hemophagocytic lymphohistiocytosis is a rare but potentially fatal condition in which histiocytes and lymphocytes build up in and damage organs and other blood cells.
Diagnosing Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis in a patient with Systemic Lupus Erythematosus is diagnostically challenging due to the rare presentation. Hence, we are reporting this case to alert physicians to keep a high index of suspicion in such presentations.

Methods/Case Report
We present a 37-year-old man with a past medical history of Systemic Lupus Erythematosus complicated by Lupus Nephritis on immunosuppressive therapy who presented to the emergency department with hypotension and was admitted for acute kidney injury. Prior to the presentation, he had persistent fever, myalgias, cough, mild shortness of breath, and back pain. CT Chest shows “eggshell” calcification and further parasitology evaluation revealed a diagnosis of histoplasmosis using a blood sample where intracellular Histoplasma organisms were identified. A diagnosis of Hemophagocytic lymphohistiocytosis was made clinically after “Clinical and Testing Criteria” was evaluated. Despite further management, he developed coagulopathy and sepsis which led to his death.

Results (if a Case Study enter NA)
At autopsy, we found organomegaly of the liver, spleen, and kidneys.
Microscopically, these enlarged organs show old fibrotic granulomas and granulomatous inflammation with suspected fungal organisms. Periodic Acid Schiff (Fungus) and Gomori's Methenamine Silver special stain confirm these fungal organisms to be consistent with Histoplasma species (3-5 micron budding yeasts).

Conclusion
This case report highlights that physicians should be aware of the diagnostic challenge that Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis could pose in patients with Systemic Lupus Erythematosus, especially those on immunosuppression. The clinical presentation could easily mimic a flare of Systemic Lupus Erythematosus, leading to more aggressive immunosuppression. Failure to recognize the infection promptly could lead to grievous complications and sometimes death.
Ossifying Fibromyxoid Tumor with Atypical Features: A Case Report and Review of Literature
Authors: Belogrivtseva Y , Lazim A , Taraif S 
Published: November 2023

Abstract

Introduction/Objective
Ossifying fibromyxoid tumor (OFMT) is a soft tissue neoplasm usually behaving in a benign fashion, however, it can rarely show atypical or malignant features. It most frequently occurs within the extremities and trunk. Although OFMTs are translocation-associated tumors, and very commonly associated with recurrent gene rearrangements involving the PHF1 gene, their morphologic and immunophenotypic profile can overlap with other soft tissue tumors posing a diagnostic challenge.

Methods/Case Report
Herein we present a case of a 23-year-old woman who had an excision of a subcutaneous shoulder mass. Grossly, the 5.3 cm mass had a thin translucent capsule and a pink, soft-cut surface with scattered calcifications. Microscopic examination revealed a well-circumscribed lesion composed of plump spindle cells with uniform oval nuclei arranged in short fascicles within a mildly collagenous background. There was prominent hemangiopericytoma-like vasculature and foci of ossification. The tumor cells contained moderate cytoplasm and showed a mild degree of nuclear atypia. Mitotic activity was up to 6 per 10 high-power fields. Immunohistochemical stains showed tumor cells are positive for Desmin, SMA, AE1/AE3 (patchy), TLE, and SATB2, while negative for CD31, CD34, S-100, C-kit, DOG-1, CD117, HMB-45, Melan-A, ALK-1, SOX10, Inhibin, and STAT6. Ki-67 proliferation index was low (1-2%). Fluorescence in situ hybridization (FISH) testing was negative for SYT and MDM2 gene amplification. FISH testing for PHF1 gene (using experimental probes) showed a break apart signal in a subset (~ 25%) of tumor cells, which is equivocal but insufficient to establish clonal interchromosomal translocation involving PHF1.

Results (if a Case Study enter NA)
NA

Conclusion
There is a histologic spectrum and morphologic overlap of OFMTs with several other soft tissue neoplasms. OFMT with atypical features (increased cellularity and mitotic activity), as in this case, may harbor the unpredictable biologic potential for recurrence and metastasis. Additional studies are required to discover a morphologic, immunohistochemical, and possibly molecular pattern that will help to differentiate OFMT subtypes.