bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the influence of fineness and content of lithium slag on the performance of cement mortar
Authors: Zhang Wei , Zhang Cheng , Song Hao
Published: August 2024

Lithium slag(LS) is industrial solid waste during the production of lithium carbonate. LS has pozzolanic effect and replace cement to achieve the purpose of protecting the environment and saving resources. In order to clarify the influence of fineness and content of LS on the performance of cement mortar. The effects of different fineness and content of LS powder on the workability, mechanical properties and microscopic properties of cement mortar were studied. The results shown that the grinding time refined the particle size of LS and increased the particle content in the range of 0.95μm~5.68μm. Fineness of LS had little effect on the workability and mechanical properties of cement mortar. Excessive LS had significant negative impact on workability and mechanical properties of cement mortar. When the content of LS was 10 %, the heat release, the production of Ca(OH)2 and ettringite of cement paste increased. Early mechanical property of cement mortar was unreduced and effectively improved later mechanical properties under this content. The research can provide data support for the application of LS in practical engineering.
Synthesis and characterization of Co3O4/Ti3C2 MXene nanocomposite: efficient catalyst for oxygen evolution reaction application
Authors: Kamakshi Pamula , Chandrappan Joshitha , Chella Santhosh , Krishnamoorthy Ganesh Kumar
Published: August 2024

In this investigation, cube-shaped Co3O4 nanoparticles and Co3O4/Ti3C2 MXene nanocomposite were successfully prepared through the solvothermal method. XRD analysis substantiated the cubic structure formation in Co3O4. Morphological and compositional analyses were conducted using FESEM and EDS analysis. The chemical states and surface properties of the materials were explored through XPS analysis. The characterized pristine and composite electro-catalysts were evaluated for oxygen evolution reaction. Co3O4/Ti3C2 MXene nanocomposite catalyst showed reduced over potential of 454 mV. The parameters of Co3O4/Ti3C2 MXene nanocomposite significantly enhanced the kinetics of oxygen evolution reaction than the bare Co3O4 nanoparticles.
Information and thermodynamic entropies of regioisomeric fullerene cycloadducts C60(CH2)n (n = 1, 2) and C70CH2
Authors: Tukhbatullina Alina , Turbin Aleksandr , Sabirov Denis
Published: August 2024

The computations of the thermodynamic and information entropies of regioisomeric mono- and bisadducts of the C60 and C70 fullerenes with cyclopropane addends were performed with the density functional theory method. The regularities between the entropies and symmetry point groups of the molecules are discussed. For isomeric compounds, the calculated thermodynamic and information entropies vary in narrow ranges; the ranges for both entropies are narrower as compared with the ranges observed for these quantities of fullerenes themselves. The information entropy is recommended as a parameter for digital selecting the most and least symmetric structures.
About fractal models of clouds
Authors: Levy Jean-Claude Serge , Perreau Michel
Published: August 2024

In order to deal concretely with the full diversity and complexity of clouds, we propose here a model of clouds issued from fractals and able to deal with both gravity and wind anisotropy. The goal of this approach is to fit with the observations of infrared resonances and diffraction on clouds. These simple models derive from the well-known model of Menger sponges and takes into account both gravity and wind effect. The analysis of the connectivity matrix of this fractal model for different vertical behaviors enables us to derive a classification of these fractal clouds.
Vendace populations on the life table: between-lake variation and the association between early life and mature survival and growth
Authors: Marjomäki Timo J. , Auvinen Heikki , Helminen Harri , Huusko Ari , Huuskonen Hannu , Hyvärinen Pekka , Jurvelius Juha , Karels Aarno , Sarvala Jouko , Valkeajärvi Pentti , Karjalainen Juha
Published: August 2024

The vital rates related to reproduction and survival dictate the resistance and persistence of a population under perturbations. Freshwater fishes perform high levels of phenotypic plasticity thus these rates may differ widely between populations and temporally within a population. Knowledge of their ranges enables understanding the scope of population persistence and predicting the effects of environmental stressors. Time series of vendace (Coregonus albula) catch samples from 22 lakes were applied to estimate the lake-specific average length-at-age and survival in mature age groups (mS). Assuming an age-at-maturity of 2 yr and a constant length–fecundity relationship, survival from spawning to age 1 (firstS) and 2 (premS, prematurity survival) were estimated using a life table assuming a stable state. The average length at age 2 yr (L2) varied two-fold between populations, <100 – > 200 mm, and the estimated fecundity approximately eight-fold. Also, mS varied considerably, <10–70%a−1. L2 and mS were positively associated. The premS estimate varied ∼30-fold among lakes, <0.01 – > 0.2% per 2 yr, being highest in populations with low L2 and fecundity combined with low mS. The range of firstS estimate was even higher, 0.01–2%. This high between-lake variability seems to occur especially after hatching during the first summer. Its level is set by the factors external to the population, e.g., the abundance of key predators. Persistence with low early life survival is possible because of the wide scope of compensation in the size- and fecundity-at-age and mS. Early life survival is expected to decrease due to climate change while the compensation has its limits, increasing the risk of local extinctions.
Evaluation of early marginal bone loss around posterior dental implants placed in axial and non-axial positions: a retrospective cone beam computed tomography (CBCT) analysis
Authors: Sruthima Gottumukkala Naga Venkata Satya , Duddukuri Murali Krishna , Penmetsa Gautami S. , Satyanarayana Raju Mantena , Venkata Ramesh Konathala Santosh , Mohan Kumar Pasupuleti , valli Veluri Sathya
Published: August 2024

Introduction: To retrospectively assess the mesio-distal angular deviation/inclination of single implants restored in the posterior edentulous arches and evaluate the effect of angular deviations on the early bone loss after 12 months of functional implant loading. Materials and methods: This retrospective Cone beam computed tomography (CBCT) analysis assessed 60 single implants including 36 axially placed (AX Group) and 24 non-axially (NAX Group) placed implants of dimension 4.2 × 10 mm. Marginal bone loss (Mesial, Distal) was assessed at 1 year post implant loading in both maxillary and mandibular implants. Independent sample t-test was done for intergroup comparison and paired t-test for intragroup comparisons. Results: Mean MBL was significantly greater (P-0.02) in NAX group compared to AX group on both mesial and distal sides. Maxillary implants showed greater MBL (3.17 ± 1.33, 2.99 ± 1.63 on mesial and distal sides respectively) compared to mandibular implants (1.86 ± 0.53, 2.29 ± 0.90 on mesial and distal sides respectively). Conclusion: Greater mean MBL during first year of functional loading in NAX group and maxillary implants was observed with minimal post-operative complications and good survival rate in both groups.
Chylöser Aszites bei NSCLC: Nicht alles ist maligne, was maligne aussieht
Authors: Uhlenbruch Mark , Bärmann Marie-Kristin , Bertram Volker , Krüger Stefan
Published: August 2024

Die Ätiologie chylöser Aszites ist multifaktoriell. Maligne Grunderkrankungen, Leberzirrhose, Traumata, Lymphanomalien und Mykobakteriosen sind die häufigsten Ursachen. Bei NSCLC wird chylöser Aszites bei einer peritonealen Metastasierung oder abdomineller Lymphknotenmetastasen beobachtet.

RET-Alterationen treten bei 1–2 % der NSCLC-Patienten auf und können seit kurzem zielgerichtet therapiert werden.

Unsere Kasuistik zeigt, dass neue zielgerichtete Therapien die Prognose revolutionieren, uns aber vor die Herausforderung neuer und teils unbekannter Nebenwirkungen stellen.
Notfälle in der Medikamentösen Tumortherapie
Authors: Handke Analena , Hilser Thomas , Bögemann Martin , Schlack Katrin , Grünwald Viktor
Published: August 2024

Hintergrund Immunmodulatorische Therapien gewinnen immer größere Bedeutung in der Uro-Onkologie. Aus diesem Grund werden wir vermutlich immer häufiger mit Nebenwirkungen konfrontiert werden. Hinzu kommt eine immer größere Zahl an Kombinationen mit anderen Wirkmechanismen. Als Folge dieser Therapie können immun-vermittelte Nebenwirkungen auftreten. Diese unterscheiden sich von den Nebenwirkungen einer Chemotherapie und anderen zielgerichteten Therapien und erfordern daher andere Behandlungsstrategien.

Ziel der Arbeit Anhand der aktuellen Literatur werden die Daten zur Graduierung und stadienabhängigen Management dargelegt sowie mit Beispielen aus der Praxis anschaulich dargestellt.

Material und Methoden Literaturrecherche zur Detektion und Therapiemanagement von im Rahmen der immunonkologischen Therapie vermittelten Nebenwirkungen.

Ergebnisse Die behandlungsbezogenen Ereignisse können prinzipiell alle Organsystem betreffen, häufig finden sich Toxizitäten im Bereich der Haut, wie Ausschlag oder Pruritus, Hypo- oder Hyperthyreosen, Arthritiden, Muskelschmerzen und gastrointestinale Symptome. In der Häufigkeit sind die meisten Nebenwirkungen Grad 1 bis 2 zuzuordnen, jedoch auch Grad 3 bis 4. Toxizitäten sind grundsätzlich gut zu therapieren, sofern sie frühzeitig erkannt werden. Seltene Komplikationen wie neurologische Toxizitäten, Pneumonitis oder auch Karditis können bei zu später Diagnose einen fulminanten Verlauf entwickeln.

Diskussion Selbst Notfälle sind gut zu managen, wenn wir die wichtigsten Nebenwirkungen und therapeutischen Optionen kennen. Dabei kommt den immunvermittelten Nebenwirkungen ein besonderer Stellenwert zu, weil sie grundsätzlich jedes Organsystem betreffen können. So lange wir jedoch bei Patienten, die Symptome zeigen, an die Möglichkeit einer Toxizität durch Checkpointinhibitoren denken, sind die meisten Nebenwirkungen gut zu therapieren und daher kontrollierbar.
Anti-CD40-Antikörper stimuliert das Immunsystem
Authors: Kretzschmar Alexander
Published: August 2024

Der Anti-CD40-IgG1-Antikörper Mitazalimab wirkt als Agonist auf die dendritischen Zellen des Immunsystems. Auf dem AACR-Kongress wurden jetzt neue Daten der Studie OPTIMIZE-1 in Kombination mit einer Chemotherapie (mFOLFIRINOX) beim therapienaiven metastasierten Pankreaskarzinom vorgestellt.
Subtypbasierte Therapie des metastasierten triple-negativen Mammakarzinoms
Authors: Lorenz Judith
Published: August 2024

Eine der größten Herausforderungen bei der Therapie triple-negativer Mammakarzinome stellt ihre molekulare Heterogenität dar. Diese ist der Grund für das unterschiedliche Ansprechen der Tumoren auf die systemische Therapie. Ein Forscherteam aus Shanghai entwickelte eine subtypbasierte Erstlinientherapie und testete nun deren Sicherheit und Wirksamkeit im Rahmen einer randomisierten kontrollierten Phase-II-Studie.
Diagnostischer Mehrwert durch Proteogenomik
Authors: Kretzschmar Alexander
Published: August 2024

Die Kenntnisse zur genetischen Variabilität der diffusen großzelligen B-Zell-Lymphome (DLBCL) haben sich in den letzten Jahren deutlich erweitert. Gerade bei Hochrisiko-DLBCL-Patient*innen mit einem hohen Anteil von Chemoimmuntherapie-Resistenzen kann hier nach Ansicht von Prof. Dr. Thomas Oellerich, Frankfurt/Main, die Proteomik über rein genetisch basierte Modelle noch einen wichtigen zusätzlichen Beitrag für einen integrierten proteogenomischen Ansatz zur Verbesserung der klinischen Outcomes liefern. Oellerich stellte die Rationale für den vermehrten Einsatz der Proteogenomik auf dem West German Lymphoma Symposium in Essen vor.
The Effects of Employment Status and Daily Routines on
Fibromyalgia
Authors: Aydin Saliha , Ozsoy-Unubol Tugba
Published: August 2024

Introduction Fibromyalgia (FM) is a complex and debilitating condition
characterised by chronic pain, fatigue, sleep and mood disturbances. This study
aimed to investigate the impact of employment status and daily routines on FM
symptoms.

Methods This cross-sectional study included female FM patients meeting the
diagnostic criteria of the American College of Rheumatology. Participants’
employment status, daily routines, FM symptoms, and psychological well-being
were assessed using various scales. The relationship between the variables was
also examined.

Results Of the 74 female FM patients included, those who were employed
exhibited better health outcomes, including reduced symptom severity and
improved functionality. Engaging in exercise and reading books were associated
with less severe FM symptoms. The frequency of going out during lockdown was
positively correlated with FM symptom severity. House cleaning was linked to
improved emotional well-being, while social media use, watching TV, and
household size had no significant impact on the FM burden.

Conclusion This study highlights the positive effects of employment,
exercise, and reading on FM symptoms and emphasises the importance of a
multi-modal approach to FM management. The findings also suggest that external
stressors such as the frequency of going out during a pandemic may influence the
course of FM. These insights may inform strategies to enhance the quality of
life for individuals living with FM.
Intracranial compliance in patients with COVID-19: a multicenter observational study
Authors: Silveira Ana Flávia , Santos Marcella Barreto , Collange Nelci Zanon , Hayashi Cintya Yukie , Vilela Gustavo Henrique Frigieri , Almeida Samantha Longhi Simões de , Andrade João Brainer Clares de , Rojas Salómon , Moraes Fabiano Moulin de , Veiga Viviane Cordeiro , Flato Uri Adrian Prync , Russo Thiago Luiz , Silva Gisele Sampaio
Published: August 2024

Background Patients with severe coronavirus disease-19 (COVID-19) may require the use of invasive mechanical ventilation (MV) for prolonged periods. Aggressive MV parameters have been associated with changes in intracranial pressure (ICP) in patients with acute intracranial disorders. Significant ICP elevation could compromise intracranial compliance (ICC) and cerebrovascular hemodynamics (CVH). However, the effects of these parameters in individuals without neurological disorders have not yet been evaluated.

Objective To evaluate ICC in patients on MV with COVID-19 infection compared to other diagnoses, to better characterize the effects of MV and COVID-19 upon ICC. We also compared between the ICC in patients with COVID-19 who did not require MV and healthy volunteers, to assess the isolated effect of COVID-19 upon ICC.

Methods This was an exploratory, observational study with a convenience sample. The ICC was evaluated with a noninvasive ICP monitoring device. The P2/P1 ratio was calculated by dividing the amplitude of these two points, being defined as “abnormal” when P2 > P1. The statistical analysis was performed using a mixed linear model with random effects to compare the P2/P1 ratio in all four groups on the first monitoring day.

Results A convenience sample of 78 subjects (15 MV-COVID-19, 15 MV non-COVID-19, 24 non-MV-COVID-19, and 24 healthy participants) was prospectively enrolled. There was no difference in P2/P1 ratios between MV patients with and without COVID-19, nor between non-MV patients with COVID-19 and healthy volunteers. However, the P2/P1 ratio was higher in COVID-19 patients with MV use than in those without it.

Conclusion This exploratory analysis suggests that COVID-19 does not impair ICC.
Potentially preventing pericyte contraction in low-oxygen environments
Authors: Shapiro Maura
Published: August 2024

Contraction cytometry used to investigate pericyte mechanics and revealed a potential to reduce lasting damage from ischemic strokes.
Exploring new logic devices: Unlocking potential with floating-gate transistor
Authors: Lee Chungryeol , Choi Junhwan , Lee Changhyeon , Yoo Hocheon , Im Sung Gap
Published: August 2024

Floating-gate devices occupy a pivotal position in contemporary electronic systems, owing to their versatile capabilities in nonvolatile memory storage, analog circuit design, and emerging applications in neuromorphic computing. These devices leverage a distinctive floating-gate structure isolated from the surrounding circuitry, enabling the storage and manipulation of charge. The ability to retain charges even without external power makes them ideal for the applications requiring persistent data storage. This review explores the fundamental principles of floating-gate devices, focusing on their application in emerging logic devices combining floating-gate structures such as (i) reconfigurable logics, (ii) multi-valued logics, (iii) neuromorphic logics, and (iv) in-sensor computing. Various types of floating-gate devices for these new concept logics are examined, highlighting their key characteristics and advantages. Potential solutions and future research directions are also discussed. Based on the comprehensive review of recent three-year studies, we aim to provide an overview of floating-gate-based logic devices, emphasizing their significance in modern electronics and their potential to enable innovative applications in the fields of logic and memory devices.
Topology during magnetic reconnection events in RFX-mod
Authors: Porcu P. , Spizzo G. , Veranda M. , Zuin M. , Agostini M. , Gobbin M. , Terranova D. ,   RFX-mod Team
Published: August 2024

This paper is devoted to the characterization of magnetohydrodynamics (MHD) tearing modes causing plasma–wall interaction (PWI) in the Reversed-Field eXperiment (RFX-mod) reversed-field pinch (RFP) device. We study an example of a magnetic reconnection event in a high plasma current discharge. The PWI is measured via a fast camera looking at the graphite-covered inner wall, showing two separated footprints of neutral carbon radiation. A first, simple analysis shows that the phase-locking of m=1 tearing modes is the principal cause of enhanced PWI, as it is well documented in literature. Many modes contribute to the phase-locking, actually more than those measured with the magnetic sensors. A more refined analysis is based on calculation of the Connection Length to the wall and of the loss time of Maxwellian ions via the Hamiltonian guiding center code Orbit. This analysis confirms the importance of the m=1 phase-locking as a loss channel of high-energy particles, which is the mechanism that dominates the PWI pattern, but an additional role of the m=0, n=7 mode is highlighted, which is a new result for the RFP. The PWI mediated by the m=0 islands is milder, which is a good outlook for the RFX-mod2 upgraded device, currently in the assembly phase.
X-ray imaging and electron temperature evolution in laser-driven magnetic reconnection experiments at the national ignition facility
Authors: Valenzuela-Villaseca Vicente , Molina Jacob M. , Schaeffer Derek B. , Malko Sophia , Griff-McMahon Jesse , Lezhnin Kirill , Rosenberg Michael J. , Hu S. X. , Kalantar Dan , Trosseille Clement , Park Hye-Sook , Remington Bruce A. , Fiksel Gennady , Uzdensky Dmitri , Bhattacharjee Amitava , Fox William
Published: August 2024

We present results from x-ray imaging of high-aspect-ratio magnetic reconnection experiments driven at the National Ignition Facility. Two parallel, self-magnetized, elongated laser-driven plumes are produced by tiling 40 laser beams. A magnetic reconnection layer is formed by the collision of the plumes. A gated x-ray framing pinhole camera with micro-channel plate detector produces multiple images through various filters of the formation and evolution of both the plumes and current sheet. As the diagnostic integrates plasma self-emission along the line of sight, two-dimensional electron temperature maps ⟨Te⟩Y are constructed by taking the ratio of intensity of these images obtained with different filters. The plumes have a characteristic temperature ⟨Te⟩Y=240 ± 20 eV at 2 ns after the initial laser irradiation and exhibit a slow cooling up to 4 ns. The reconnection layer forms at 3 ns with a temperature ⟨Te⟩Y=280 ± 50 eV as the result of the collision of the plumes. The error bars of the plumes and current sheet temperatures separate at 4 ns, showing the heating of the current sheet from colder inflows. Using a semi-analytical model, we survey various heating mechanisms in the current sheet. We find that reconnection energy conversion would dominate at low density (ne≲7×1018 cm−3) and electron-ion collisional drag at high-density (≳1019 cm−3).
Analysis of space charge and current characters of oil-immersed-paper with simultaneous measurement
Authors: Ma Yuntong , Lv Zepeng , Zhang Yining , Peng Jinyang , Ge Yi , Wu Kai , Cheng Yonghong
Published: August 2024

To study the current response to space charge in oil–paper insulation, a simultaneous space charge and external current measurement system are developed for a solid–liquid sample. The space charge and external current of oil-immersed paper are tested under different applied voltages. In the oil–paper sample, it accumulates heterocharge at 0.25 kV and homocharge at a higher voltage. The external currents first decrease and then increase with time. The changing timepoint decreases with the applied voltage. It shows that dynamic space charge evolution influences external current development. An unusual phenomenon is observed that the charge on both electrodes increases without heterocharge accumulation in a certain time range after voltage application, resulting in an increase in the average electric field. The transient electric field and displacement current at the cathode are calculated according to the amount of surface charge at the cathode. It indicates that displacement current takes up the main part of external current and decreases to zero when the surface charge amount stops increasing. After this stage, the conduction current is almost equal to the external current. The correlation between conduction current and electric field is analyzed. It reveals that when the electric field is lower than 5 kV/mm, the conduction current of oil–paper seems to be linear to the electric field strength, following Ohm’s law. When the electric field is higher than 5 kV/mm, the conduction current of oil–paper follows the Fowler–Nordheim law that the ln(jc/E2) is linear to 1/E. The transient external current has great potential in diagnosing electrical equipment.
Deep-learning design of electronic metasurfaces in graphene for quantum control and Dirac electron holography
Authors: Han Chen-Di , Ye Li-Li , Lin Zin , Kovanis Vassilios , Lai Ying-Cheng
Published: August 2024

Metasurfaces are sub-wavelength patterned layers for controlling waves in physical systems. In optics, metasurfaces are created by materials with different dielectric constants and are capable of unconventional functionalities. We develop a deep-learning framework for Dirac-material metasurface design for controlling electronic waves. The metasurface is a configuration of circular graphene quantum dots, each created by an electric potential. Employing deep convolutional neural networks, we show that the original scattering wave can be reconstructed with fidelity over 95%, suggesting the feasibility of Dirac electron holography. Additional applications such as plane wave generation and designing broadband and multi-functionality electronic metasurface in graphene are illustrated.
dxtb—An efficient and fully differentiable framework for extended tight-binding
Authors: Friede Marvin , Hölzer Christian , Ehlert Sebastian , Grimme Stefan
Published: August 2024

Automatic differentiation (AD) emerged as an integral part of machine learning, accelerating model development by enabling gradient-based optimization without explicit analytical derivatives. Recently, the benefits of AD and computing arbitrary-order derivatives with respect to any variable were also recognized in the field of quantum chemistry. In this work, we present dxtb—an open-source, fully differentiable framework for semiempirical extended tight-binding (xTB) methods. Developed entirely in Python and leveraging PyTorch for array operations, dxtb facilitates extensibility and rapid prototyping while maintaining computational efficiency. Through comprehensive code vectorization and optimization, we essentially reach the speed of compiled xTB programs for high-throughput calculations of small molecules. The excellent performance also scales to large systems, and batch operability yields additional benefits for execution on parallel hardware. In particular, energy evaluations are on par with existing programs, whereas the speed of automatically differentiated nuclear derivatives is only 2 to 5 times slower compared to their analytical counterparts. We showcase the utility of AD in dxtb by calculating various molecular and spectroscopic properties, highlighting its capacity to enhance and simplify such evaluations. Furthermore, the framework streamlines optimization tasks and offers seamless integration of semiempirical quantum chemistry in machine learning, paving the way for physics-inspired end-to-end differentiable models. Ultimately, dxtb aims to further advance the capabilities of semiempirical methods, providing an extensible foundation for future developments and hybrid machine learning applications. The framework is accessible at https://github.com/grimme-lab/dxtb.
Unveiling the electron-induced ionization cross sections and fragmentation mechanisms of 3,4-dihydro-2H-pyran
Authors: Wasowicz Tomasz J. , Jurkowski Michal K. , Harris Allison L. , Ljubić Ivan
Published: August 2024

The interactions of electrons with molecular systems under various conditions are essential to interdisciplinary research fields extending over the fundamental and applied sciences. In particular, investigating electron-induced ionization and dissociation of molecules may shed light on the radiation damage to living cells, the physicochemical processes in interstellar environments, and reaction mechanisms occurring in combustion or plasma. We have, therefore, studied electron-induced ionization and dissociation of the gas phase 3,4-dihydro-2H-pyran (DHP), a cyclic ether appearing to be a viable moiety for developing efficient clinical pharmacokinetics and revealing the mechanisms of biofuel combustion. The mass spectra in the m/z = 10–90 mass range were measured at several different energies of the ionizing electron beam using mass spectrometry. The mass spectra of DHP at the same energies were simulated using on-the-fly semi-classical molecular dynamics (MD) within the framework of the QCxMS formalism. The MD settings were suitably adjusted until a good agreement with the experimental mass spectra intensities was achieved, thus enabling a reliable assignment of cations and unraveling the plausible fragmentation channels. Based on the measurement of the absolute total ionization cross section of DHP (18.1 ± 0.9) × 10−16 cm2 at 100 eV energy, the absolute total and partial ionization cross sections of DHP were determined in the 5–140 eV electron energy. Moreover, a machine learning algorithm that was trained with measured cross sections from 25 different molecules was used to predict the total ionization cross section for DHP. Comparison of the machine learning simulation with the measured data showed acceptable agreement, similar to that achieved in past predictions of the algorithm.
Considerations for ultrafast photomagnetism in manganese(III)-based single-molecule magnets
Authors: Barlow K. , Johansson J. O.
Published: August 2024

Manipulation of magnetic materials is a cornerstone of digital data storage technologies. Recently, it has been shown that femtosecond laser pulses are capable of switching the magnetization in a material between two stable configurations faster than ever before. One state-of-the-art method is to use laser pulses to control the magnetic anisotropy by photoexciting crystal-field transitions. The photoinduced change in anisotropy applies a torque to the magnetic moment, which reorientates it in a different direction. So far, research has focused solely on condensed matter materials. However, there is a huge variety of molecule-based magnetic materials that have been and continue to be developed. In particular, single-molecule magnets (SMMs) provide a highly tunable platform and have the added advantage of operating on nanometer length scales. This review discusses recent research in the area of ultrafast magnetism in SMMs, with a focus on manganese(III)-based transition metal complexes. Experimental data are reviewed, showing that control of the strength of the photoinduced anisotropy, the lifetime of excited states, and the dephasing times are possible and can be used to develop some design criteria for the best optically controllable SMMs.
Enhancing device characteristics of pentacene-based organic transistors through graphene integration: A simulation study and performance analysis
Authors: Singh Manish Kumar , Anusha Kadiyam , Dwivedi A. D. D.
Published: August 2024

Transistors find application within various integrated circuits (ICs) alongside a multitude of electronic devices. These ICs have become integral components in contemporary systems. When organic semiconducting materials constitute the active layer, transistors are termed “organic transistors.” The enhancement of diverse device characteristics is achievable through the modeling and simulation of these organic transistors. This study focuses on the simulation of different configurations of pentacene-based organic transistors. To augment device performance, an active layer comprising pentacene is coupled with 5 and 15 nm graphene. Notably, the top gate configuration yields an increase in ON/OFF ratio from 102 to 107, accompanied by an enhancement in sub-threshold swing from 276 to 59 mV/decade. Similarly, the bottom gate configuration exhibits an ON/OFF ratio improvement from 105 to 109, alongside a sub-threshold swing enhancement from 108 to 59 mV/decade. Leveraging graphene as the active layer material results in substantial benefits. These encompass a heightened on-current of 210 mA, a reduced sub-threshold swing of 58 mV/decade, and a significantly enhanced ON/OFF ratio of 1017.
A gradient-improved sampling plan for surrogate-based aerodynamic shape optimization using discontinuous Galerkin methods
Authors: Feng Yiwei , Lv Lili , Yan Xiaomeng , Ai Bangcheng , Liu Tiegang
Published: August 2024

Surrogate-based optimization (SBO) is a powerful approach for global optimization of high-dimensional expensive black-box functions, commonly consisting of four modules: design of experiment, function evaluation, surrogate construction, and infill sampling criterion. This work develops a robust and efficient SBO framework for aerodynamic shape optimization using discontinuous Galerkin methods as the computational fluid dynamics evaluation. Innovatively, the prior adjoint gradient information of the baseline shape is used to improve the performance of the sampling plan in the preliminary design of the experiment stage and further improve the robustness and efficiency of the construction of surrogate(s). Specifically, the initial sample points along the direction of objective rise have a high probability of being transformed into feasible points in a subspace of objective descending. Numerical experiments verified that the proposed gradient-improved sampling plan is capable of stably exploring the design space of objective descending and constraint satisfaction even with limited sample points, which leads to a stable improvement of the resultant aerodynamic performance of the final optimized shape.
Effect of grain boundary segregation of rare earth element on deformation behavior of Mg alloys
Authors: Li S. , Song H. Y.
Published: August 2024

Alloying with rare earth (RE) elements is an effective way to improve the mechanical properties of the Mg alloys. However, the strengthening mechanism of RE element Y on the Mg alloys still needs to be further revealed. The effect of grain boundary (GB) segregation of RE element Y on the mechanical properties and the GB stability of the Mg alloys are investigated by the molecular dynamics simulation method. The results show that the GB segregation of Y atoms can significantly increase the yield strength and GB stability of the Mg alloys. The higher the content of Y atoms at the GB, the stronger the stability of the GB and the higher the strength of the alloys. The results also show that the GBs thicken significantly with increasing Y content at the GBs, which is attributed to the diffusion of Y atoms, leading to the solid-state amorphization of the Mg alloys. The results indicate that with the increase of Y content at the GBs, the Mg alloys undergo a transition from the plastic deformation dominated by the co-sliding of GBs and dislocations to the slip of dislocations only. This work provides a theoretical basis for the design and preparation of high-performance Mg alloys.
Experiment and numerical investigation on internal ballistic characteristics of L-type impulse thruster
Authors: Su Dongjian , An Qingwei , Xue Shao , Wang Hao , Tao Ruyi
Published: August 2024

The impulse thruster exhibits the advantages of the simplistic structure and rapid response speed. It is often used for the attitude adjustment and orbit control of the aircraft and space vehicle. In order to study the internal ballistic variation law and the flow characteristics of the gunpowder gas, the interior working process of the L-type impulse thruster was investigated by the numerical simulation and experimental verification. First, an internal ballistic test was designed and conducted, and the change process of the thrust and pressure over time was measured, and the feasibility and rationality of the impulse thruster design were verified. Second, a three-dimensional internal ballistic model of the L-type impulse thruster including the ignition process was established. With the help of the dynamic mesh technology and secondary development capability of the user-defined function in the software Fluent, the coupling process of the propellant combustion and internal flow field change of the gunpowder gas was realized. The calculated results were in good agreement with the test data. Finally, the distribution of the pressure and velocity in the flow field was analyzed in detail, and the variation law of the thrust characteristics with the nozzle length and the expansion ratio was studied, which could provide the essential data for further optimization design research. The outcomes from this paper can offer technical means for advancing studies on the internal ballistic changing law of the L-type impulse thruster.
Regarding the extension of metaplectic geometrical optics to modeling evanescent waves in ray-tracing codes
Authors: Lopez N. A. , Højlund R. , Senstius M. G.
Published: August 2024

Metaplectic geometrical optics (MGO) is a recently developed ray-tracing framework to accurately compute the wavefield behavior near a caustic (turning point or focal point), where traditional ray-tracing breaks down. However, MGO has thus far been restricted to having real-valued wavevectors. This is disadvantageous because often upon crossing a caustic from the “illuminated” region to the “shadow” region, two real-valued rays coalesce into one complex-valued ray corresponding to the transition from propagating to evanescent behavior. One can distinguish caustics as having either “illuminated shadows” or “proper shadows”—the former corresponds to when the shadow still contains real-valued rays (albeit in a fewer quantity than in the illuminated region), while the latter corresponds to when the shadow contains no real-valued rays. Here, by means of examples, we show how MGO can be used to model both types of shadows. First, for illuminated shadows, we show that MGO can actually be used “as is,” provided a corrected integration scheme is used compared to that proposed in the original references. This is then implemented and demonstrated in a recently developed MGO ray-tracing code. Second, we show that for proper shadows, the MGO formalism can still be used if the symplectic rotation matrix that removes caustics along rays is allowed to be complex-valued. In both cases, strong agreement is seen between the MGO and the exact solution, demonstrating the potential of MGO for improving the predictive capability of ray-tracing codes and laying the foundations for modeling more complicated evanescent phenomena such as tunneling with MGO.
Simulation of Kitaev chain using one-dimensional chain of superconducting qubits and environmental effects on topological states
Authors: Zhang Yang , Ge Yun-Qiu , Liu Yu-xi
Published: August 2024

Kitaev chain is one of the important physical models for studying topological quantum states and quantum computing. We here propose an approach to simulate the one-dimensional Kitaev chain via a circuit of superconducting qubits. In our approach, all coupling parameters can be controlled independently, and a nontrivial gauge phase is constructed. We also study the environmental effects on the topological states of the Kitaev chain. In addition to the independent environment surrounding each qubit, we consider the common environment shared by neighboring qubits. Such an environment can generate effective non-Hermitian dissipative coupling between qubits. Through analysis and numerical calculation, we demonstrate that the common environment can significantly affect the topological properties of the qubit chain. Moreover, we observe that dissipative couplings at the edges of the Kitaev chain affect the topological states more strongly than those located elsewhere. Our work may provide a new way to explore topological phase transitions and environmental effects on topological physics using superconducting qubit circuits.
The desmosome comes into focus
Authors: Bharathan Navaneetha Krishnan , Mattheyses Alexa L. , Kowalczyk Andrew P.
Published: August 2024

The desmosome is a cell–cell adhesive junction that provides integrity and mechanical resistance to tissues through its attachment to the intermediate filament cytoskeleton. Defects in desmosomes cause diseases impacting the heart, epidermis, and other epithelia. In this review, we provide a historical perspective on the discovery of the desmosome and how the evolution of cellular imaging technologies revealed insights into desmosome structure and function. We also discuss recent findings using contemporary imaging approaches that have informed the molecular order, three-dimensional architecture, and associations of desmosomes with organelles such as the endoplasmic reticulum. Finally, we provide an updated model of desmosome molecular organization and speculate upon novel functions of this cell junction as a signaling center for sensing mechanical and other forms of cell stress.
Spontaneous anomalous Hall effect in magnetic and non-magnetic systems
Authors: Vedyayev A V , Tao L L , Zhuravlev M Ye
Published: August 2024

We consider two cases of spontaneous anomalous Hall current. In a non-magnetic system with spin–orbit coupling (SOC), the applied bias results in the appearance of non-equilibrium magnetization and an anomalous Hall current. The latter demonstrates non-linear dependence on the applied bias. In a magnetic system with SOC, an anomalous current appears without applied bias. We perform the calculations in the framework of the free-electron model, whereas the common approach to this type of phenomenon is based on Berry connection. We demonstrate that anomalous currents acquire a measurable magnitude for reasonable model parameters.
Morphological characterization of concave particle based on convex decomposition
Authors: Du Libing , Li Zirui , Liu Xinrong , Yang Zhongping
Published: August 2024

Particle morphology is an important factor affecting the mechanical properties of granular materials. However, it is difficult to quantify the morphology characteristics of the complex concave particle. Fortunately, complex particle can be segmented by convex decomposition, so a new shape index named convex decomposition coefficient (CDC) related to the number of segmentations is proposed. First, the pocket concavity was introduced to simplify the morphology hierarchically. Second, the cut weight linked to concavity was defined and convex decomposition was linearly optimised by maximizing the total cut weights. Third, the CDC was defined as the minimum block number where the block area ratio cumulatively exceeded 0.9 in descending order. Finally, the proposed index was used to quantify the particle morphology of coral sand. The results demonstrate that the CDC of coral sands mainly ranges from 2 to 6, with a positively skewed distribution. Furthermore, CDC correlates well with three shape indices: sphericity, particle size, and convexity. Larger CDC is associated with smaller sphericity, larger particle size, and smaller convexity. The index has certain scientific research value and practical significance.
A convenient analytical parametrization of a tokamak plasma last closed flux surface for use in shape and discharge design
Authors: Fable E
Published: August 2024

An analytical parametrization of the last closed flux surface of a tokamak plasma is proposed, based on a reduced list of global shape parameters that are conveniently defined. This parametrization can reproduce a variety of shapes, from limited to diverted, lower and upper single null, double null, and diverted negative triangularity plasmas. The choice of the parameters is well suited to be used for easy shape and more generally discharge design, in view of fitting the coil currents that are required to form the desired shape.
Design of a novel intelligent adaptive fractional-order proportional-integral-derivative controller for mitigation of seismic vibrations of a building equipped with an active tuned mass damper
Authors: Jafarzadeh Ommegolsoum , Sabetahd Rasoul , Mousavi Ghasemi Seyyed Arash , Zahrai Seyed Mehdi
Published: August 2024

The primary objective of this study is to introduce a novel adaptive fractional order proportional–integral–derivative (FOPID) controller. The adaptive FOPID controller’s parameters are dynamically adjusted in real-time using five distinct multilayer perceptron neural networks. The extended Kalman filter (EKF) is employed to facilitate the parameter-tuning process. A multilayer perceptron neural network, trained using the error Backpropagation algorithm, is employed to identify the structural system and estimate the plant. The real-time estimated Jacobian is applied to the controller to control the model. The stability and robustness of the adaptive interval type-2 fuzzy neural networks controller are enhanced by utilizing the EKF and the feedback error learning strategy for compensator tuning. This improvement increases resilience against estimation errors, seismic disturbances, and unknown nonlinear functions. The primary objective is to address the challenges posed by maximum displacement, acceleration, and drift, as well as the uncertainties arising from variations in stiffness and mass. In order to validate the reliability of the proposed controller, the performance investigation is carried out on an 11-story building equipped with an active tuned mass damper under far and near-field earthquakes. Numerical findings show the remarkable effectiveness of the proposed controllers compared to their predecessors. In addition, it is revealed that the inclusion of the adaptive interval type-2 fuzzy neural networks compensator has increased the performance of the proposed controller and shows significant capabilities in reducing the seismic responses of structures during severe earthquake events.
Admittance-based equivalent circuit modeling of multi-patch piezoelectric energy harvesting plate
Authors: Simsek Mehmet , Aghakhani Amirreza , Basdogan Ipek
Published: August 2024

Harvesting energy from mechanical vibration using piezoelectric material is a common method to power small electronics and batteries. Implementation of multiple piezo-patches to plate-like structures increases the power capacity and frequency bandwidth of the energy harvester since multiple patches can capture more vibrational modes of the dense plate dynamics. To optimize the harvested electrical output using advanced harvesting circuits, equivalent circuit modeling (ECM) is a useful technique for representing the entire electromechanical system in circuit- simulator-software (LTspice). The ECM technique based on finite-element (FE) simulation has been used for plate-like structures with only one single-piezo-patch-harvester in the literature. However, when multiple patches are integrated into a plate-like structure, their coupling can cause charge cancelation, resulting in complex dynamics that cannot be handled by the existing ECM methods. This paper presents three new methodologies for extracting a multi-mode ECM of the harvesters (e.g.: multi-patch piezo-harvesters integrated into a plate), using an admittance-based system identification approach utilizing FE results. The first method incorporates the ECM of multi-patch harvester into a single ECM, so called OGC. It includes a circuit branch where multiple patches have only one ECM branch for each vibration mode, which requires less equivalent circuit elements and hence less computational cost. The second and third so-called respective ground uncoupled (RGU) and respective ground coupled (RGC) ECM methods generate circuit branches for each piezo-patch and for each vibration mode, whereby their electrical connection (e.g. parallel or series) is later configured in LTspice. The RGU method provides a general multi-patch modeling approach while RGC method provides ECM parameters for each patch simultaneously when they are all connected which is the case in network harvester analysis. The ECMs of parallel multi-patch harvesters are validated by system-level FE simulations. The proposed admittance-based ECM methods are reliable for deriving the system parameters of multi-patch harvesters.
SuperSIM: a comprehensive benchmarking framework for neural networks using superconductor Josephson devices
Authors: Zhu Guangxian , Kan Yirong , Zhang Renyuan , Nakashima Yasuhiko , Luo Wenhui , Takeuchi Naoki , Yoshikawa Nobuyuki , Chen Olivia
Published: August 2024

This paper introduces SuperSIM, a benchmarking framework tailored for neural networks using superconducting Josephson devices, specifically focusing on Adiabatic Quantum Flux Parametron (AQFP) based Processing-in-Memory (PIM) architectures. Our framework offers in-depth architecture-level simulations and performance assessments to enhance AQFP PIM chip development. It supports single and multi-bit PIM designs, various AQFP memory cell types, and diverse clocking methods. Additionally, it integrates circuit-level models for precise energy, delay, and area measurements, ensuring accurate performance evaluation. The framework includes application, device, and architectural layers for versatile configurations and cycle-accurate energy, latency, and area simulations. Experiments validate our framework, with case studies on algorithm and architecture-level features, examining data precision, crossbar size, operating frequency and clocking scheme impacts on computational accuracy, energy use, overall latency and hardware cost.