bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantum simulation of Maxwell’s equations via Schrödingerisation
Authors: Jin Shi , Liu Nana , Ma Chuwen
Published: June 2024

We present quantum algorithms for electromagnetic fields governed by Maxwell’s equations. The algorithms are based on the Schrödingerisation approach, which transforms any linear PDEs and ODEs with non-unitary dynamics into a system evolving under unitary dynamics, via a warped phase transformation that maps the equation into one higher dimension. In this paper, our quantum algorithms are based on either a direct approximation of Maxwell’s equations combined with Yee’s algorithm, or a matrix representation in terms of Riemann–Silberstein vectors combined with a spectral approach and an upwind scheme. We implement these algorithms with physical boundary conditions, including perfect conductor and impedance boundaries. We also solve Maxwell’s equations for a linear inhomogeneous medium, specifically the interface problem. Several numerical experiments are performed to demonstrate the validity of this approach. In addition, instead of qubits, the quantum algorithms can also be formulated in the continuous variable quantum framework, which allows the quantum simulation of Maxwell’s equations in analog quantum simulation.
Patient-specific input data for predictive modelling of the Fontan procedure
Authors: Dobroserdova Tatiana , Yurpolskaya Lyudmila , Vassilevski Yuri , Svobodov Andrey
Published: June 2024

Personalized blood flow models are used for optimization of the Fontan procedure. In this paper we discuss clinical data for model initialization. Before the Fontan procedure patients undergo CT or MRI examination. Computational domain of interest is reconstructed from this data. CT images are shown to have a better spatial resolution and quality and are more suitable for segmentation. MRI data gives information about blood flow rates and it is utilized for setting boundary conditions in local 3D hemodynamic models. We discovered that the MRI data is contradictory and too inaccurate for setting boundary conditions: the error of measured velocities is comparable with blood velocities in veins. We discuss a multiscale 1D3D circulation model as potentially suitable for prediction of the Fontan procedure results. Such model may be initialized with more reliable data (MR measurements of blood flow in aorta and ultrasound examination of easily accessible vessels) and take into account collateral and fenestration blood flows which are typical for Fontan patients. We have calculated these flow rates for several patients and demonstrated that such flows occur systematically.
Daumensattelgelenk – eine Trendwende
Authors: Mühldorfer-Fodor Marion
Published: June 2024

In dieser Ausgabe der HaMiPla habe ich einige Beiträge zum Thema Sattelgelenk
zusammengefasst, die sehr gut eine Trendwende in den deutschsprachigen Ländern
widerspiegeln: In der Behandlung der Rhizarthrose wird der Endoprothetik erst in den
letzten 5 Jahren wieder großflächig Interesse entgegengebracht. Nach 2000 fand nach
den Fehlschlägen der ersten Prothesengeneration die Sattelgelenksprothese kaum
Befürworter: Daecke und Mitarb. publizierten 2005 einen Artikel zum „Stellenwert der
Endoprothetik im Bereich der Handchirurgie“ 1.
In einer Umfrage unter 150 handchirurgischen Klinik-Abteilungen und Praxen in
Deutschland standen 1556 traditionelle Operationen zur Behandlung der Rhizarthrose
nur 96 endoprothetische Eingriffen gegenüber, davon 53 Kugelkopf-Prothesen. 90,3+%
der Teilnehmer gaben an, der Endoprothetik des Sattelgelenks keine Zukunftschancen
beizumessen. Dagegen wurde in den französischsprachigen Ländern deren
Weiterentwicklung erfolgreich vorangetrieben. Die in den letzten 12 Jahren
publizierten Langzeitergebnisse verschiedener Prothesenmodelle der 2. Generation
überzeugten durch 10 Jahres-Standzeiten von deutlich über 90+%. Zwischenzeitlich
wurde die 3. Prothesengeneration implementiert. Rund 2000* Sattelgelenksprothesen
wurden 2022 in Deutschland schätzungsweise implantiert, 2023 bereits ca. 3800*,
wobei die Zahlen unserer westeuropäischen Nachbarländer nicht erreicht werden. Wie
bei vielen vielversprechenden Neuerungen ist auch für die Sattelgelenksendoprothetik
zu erwarten, dass in den nächsten Jahren dieser Trend einen Zenit überschreiten
wird. Sinnvolle Indikationen und Grenzen des Verfahrens und somit dessen Stellenwert
unter den verschiedenen Therapieoptionen gilt es nun auszuloten. Hierbei dürfte auch
die aktuell validierte deutsche Fassung des patienten-orientierten Fragebogens
„Thumb Disability Examination“ (TDX) zur spezifischen Diagnostik und
Verlaufskontrolle bei Rhizarthrose hilfreich sein, der kürzlich in der HaMiPla
6/2023 publiziert wurde 2. Im aktuellen Heft
vergleichen Windhofer und Kollegen in ihrem Beitrag relevante Fakten zur
Indikationsstellung von Resektionsarthroplastik und Endoprothetik. Herren und
Mitarb. sowie Daeschler und Mitarb. befassen sich mit Operationstechnik der
Sattelgelenksprothesen. Tosun und Mitarb. lenken mit Ergebnissen der
Resektionsarthroplastik nochmals den Blick auf den Stellenwert der traditionellen
Verfahren.
Pfannenplatzierung bei Daumensattelgelenksprothesen: Die Rolle des
Führungsdrahts
Authors: Daeschler Simeon C. , Sommer Jan , Tu Thomas Jing Zhi , Jaeger Sebastian , Knappe Kevin , Harhaus Leila , Panzram Benjamin
Published: June 2024

Hintergrund Die zunehmende Anwendung von Daumensattelgelenksprothesen bei
fortgeschrittener Rhizarthrose reflektiert den Erfolg der jüngsten
Prothesengenerationen durch ihre verbesserten funktionellen Ergebnisse und
geringeren Komplikationsraten. Eine präzise Ausrichtung der Prothesenpfanne
parallel zur proximalen Gelenkoberfläche des Trapeziums ist hierbei für die
Stabilität und Vermeidung von Luxationen essenziell. Dies stellt gerade für den
unerfahrenen „Beginner“ dieser Technik erfahrungsgemäß das größte Problem dar.
Trotz adäquater Positionierung des Führungsdrahtes können Fehlplatzierungen der
Pfanne auftreten, die eine intraoperativen Revision notwendig machen.

Material und Methoden Diese Studie untersucht die Abweichungen der
Pfannen- und Führungsdrahtpositionierung bei
Daumensattelgelenksprothesenimplantationen durch unerfahrene und erfahrene
Operateure mittels radiologischer Analyse an 65 Prothesen.

Ergebnisse Sowohl unerfahrene als auch erfahrene Operateure erreichten
eine präzise Führungsdrahtpositionierung mit mittleren Abweichungen von<2,2°.
Unerfahrene zeigten signifikant größere Pfannenabweichungen im dorsopalmaren und
lateralen Strahlengang (7,6±6,1° und 7,3±5,9°) im Vergleich zu erfahrenen
Operateuren (3,6±2,7° und 3,6±2,5°; p=0,012, p=0,017). Die Abweichung der Pfanne
zeigte bei unerfahrenen Operateuren eine jeweils entgegengesetzte
Richtungstendenz zum Führungsdraht (p<0,0038).

Schlussfolgerung Die Ergebnisse verdeutlichen die aktuellen
Herausforderungen bei der Pfannenpositionierung abhängig vom Erfahrungsgrad des
Chirurgen und hinterfragen die Zuverlässigkeit des aktuellen
Führungsdrahtsystems bei Prothesenimplantationen.
Analyzing single-action bias in dynamic climate change environments: insights from feedback and probability
Authors: Choudhary Gitanshu , Dutt Varun
Published: June 2024

“Single action bias” (SAB) characterizes individuals’ inclination to undertake only one preventive measure against climate change, disregarding potentially more effective alternatives. This bias poses a significant obstacle to comprehensive responses to climate change. While dynamic climate simulators have been developed to raise awareness of climate change and encourage pro-environmental behaviors, the prevalence of SAB within these tools remains unexplored. This study introduces the “Single Action Bias-Interactive Climate Change Simulator” (SAB-ICCS) to investigate SAB’s manifestation in dynamic scenarios. Utilizing the framework of the Interactive Climate Change Simulator (ICCS), known for its efficacy in fostering pro-environmental actions, the SAB-ICCS explores how feedback, probability, and their interplay influence SAB prevalence during climate mitigation and adaptation decision-making. A total of 160 participants were randomly assigned to four conditions in the SAB-ICCS, varying feedback presence and climate change probability. Participants engaged in climate mitigation and adaptation actions, simulating the repercussions of climate change through investment choices in climate mitigation and adaptation (consisting of three insurance plans). The study’s dependent variables were the participants’ actions towards climate mitigation and adaptation. Results revealed a substantial prevalence of single action proportion (42%) compared to other action proportions. Furthermore, the total monetary investment was significantly higher when taking optimal actions than when exhibiting SAB. Moreover, a higher probability of climate change resulted in a higher prevalence of SAB (49%) than a lower probability (35%). Interestingly, feedback availability did not significantly impact SAB prevalence. Though both feedback and the probability of climate change influenced how participants exhibited SAB, and the absolute monetary investment was also significantly affected. This research enhances our comprehension of SAB within educational climate simulations, which is vital for informing climate education and policymaking. It offers insights for policymakers and educators to develop interventions addressing SAB, enhancing climate action strategies by understanding probability and feedback influences.
Unraveling intrinsic mobility limits in two-dimensional (AlxGa1−x)2O3 alloys
Authors: Duan Xinlei , lqbal Safdar , Shi Min , Wang Bao , Liu Linhua , Yang Jia-Yue
Published: June 2024

β-(AlxGa1−x)2O3 presents a diverse material characterization exhibiting exceptional electrical and optical properties. Considering the miniaturization of gallium oxide devices, two-dimensional (AlxGa1−x)2O3 alloys, as a critical component in the formation of two-dimensional electron gases, demand an in-depth examination of their carrier transport properties. Herein, we investigate the temperature-dependent carrier mobility and scattering mechanisms of quasi-two-dimensional (2D) (AlxGa1−x)2O3 (x ≤ 5) by solving the Boltzmann transport equation from first-principles. Anisotropic electron mobility of 2D (AlxGa1−x)2O3 is limited to 30−80 cm2/Vs at room temperature, and it finds that the relatively large ion-clamped dielectric tensors (Δɛ) suggest a major scattering role for polar optical phonons. The mobility of 2D (AlxGa1−x)2 is less than that of bulk β-(AlxGa1−x)2O3 and shows no quantum effects attributed to the dangling bonds on the surface. We further demonstrate that the bandgap of 2D (AlxGa1−x)2O3 decreases with the number of layers, and the electron localization function also shows an anisotropy. This work comprehensively interprets the scattering mechanism and unintentional doping intrinsic electron mobility of (AlxGa1−x)2O3 alloys, providing physical elaboration and alternative horizons for experimental synthesis, crystallographic investigations, and power device fabrication of 2D (AlxGa1−x)2O3 atomically thin layered systems.
Numerical investigation on effects of low Reynolds number conditions on fan shaped film cooling performances
Authors: Liu Haibin , Zhang Dingcheng , Chen Pingting , Han Xingsi
Published: June 2024

This study investigates the effects of low Reynolds number (Re) conditions on the cooling performance of fan-shaped film cooling holes in the gas turbine engines of high-altitude long-endurance Unmanned Aerial Vehicles (UAVs). The significance of film cooling technology becomes paramount due to the low Re operational environment of UAVs. A novel Very Large Eddy Simulation (VLES) method was employed to systematically analyze a range of mainstream Reynolds numbers (ReD) from 480 to 32 000 and blowing ratios (M) from 1.0 to 2.5 while keeping the density ratio (DR) constant at 1.75. Compared to other turbulence models, the VLES model showed the highest similarity in predicting thermal field distributions and the most accurate prediction of film cooling performance at low Re. The results reveal that at low ReD, significant flow concentration within the hole leads to reduced velocity uniformity at the outlet, resulting in poor film coverage downstream. Additionally, the coolant jet tends to detach from the wall, adversely affecting cooling performance. In contrast, higher ReD exhibited improved coolant jet adhesion to the wall and cooling efficiency, attributed to the reduced intensity of counter-rotating vortex pair and decreased hot gas entrainment, thereby enhancing cooling effectiveness. Notably, for the same ReD values, cases with M = 1.5 consistently showed better cooling effectiveness compared to other M conditions. This study provides new insight into the cooling performance of fan-shaped film cooling holes under low Reynolds number conditions, which is crucial for enhancing the cooling efficiency of gas turbines in high-altitude UAVs.
Demonstration of proton acceleration using laser-driven EMP field in dispersion-free slow wave tube
Authors: Li Y. Z. , Li C. T. , Yan Y. , Fang Y. L. , Cheng H. , Yan Y. T. , Huang M. F. , Wu M. J. , Geng Y. X. , Zhao Y. Y. , Lin C. , Yan X. Q.
Published: June 2024

We demonstrate the laser-driven post-acceleration experiment, utilizing a miniature slow-wave structure. Experiments on a terawatt laser system showed a significant increase in proton cutoff energy, highlighting the technique's potential, especially for high-power laser systems. The slow-wave structure consists of a helix and a shielded metallic shell covered on the outside. The transmission properties of electromagnetic pulses (EMPs) generated by laser–foil interactions along the structure are studied. Through an electromagnetic field perspective, we derived dispersion relations for helices with and without metallic shield. Our findings, supported by theory, simulations, and experiments, demonstrate the structure's ability to transmit high-frequency EMPs with limited dispersion.
Linking wall shear stress and vorticity topologies: Toward a unified theory of cardiovascular flow disturbances
Authors: Mazzi Valentina , Gallo Diego , Calò Karol , Steinman David A. , Morbiducci Umberto
Published: June 2024

Broadening current knowledge about the complex relationship at the blood-vessel wall interface is a main challenge in hemodynamics research. Moving from the consideration that wall shear stress (WSS) provides a signature for the near-wall velocity dynamics and vorticity is considered the skeleton of fluid motion, here we present a unified theory demonstrating the existing link between surface vorticity (SV) and WSS topological skeletons, the latter recently emerged as a predictor of vascular disease. The analysis focused on WSS and SV fixed points, i.e., points where the fields vanish, as they play a major role in shaping the main vector field features. The theoretical analysis proves that: (i) all SV fixed points on the surface must necessarily be WSS fixed points, although with differences in nature and stability and (ii) a WSS fixed point is not necessarily a SV fixed point. In the former case, WSS fixed points are the consequence of flow patterns where only shear contributes to vorticity; in the latter case, WSS fixed points are the consequence of flow impingement to/emanation from the vessel wall. Moreover, fluid structures interacting with the wall characterized by zero or non-zero rotational momentum generate WSS fixed points of different nature/stability. High-fidelity computational fluid dynamics simulations in intracranial aneurysm models confirmed the applicability of the theoretical considerations. The presented unified theory unambiguously explains the mechanistic link between near-wall flow disturbances and the underlying intravascular flow features expressed in terms of vorticity, ultimately facilitating a clearer interpretation of the role of local hemodynamics in vascular pathophysiology.
The impact of porous structure on oil–water two-phase flow under CO2 environment in continental shale reservoirs
Authors: Meng Yufan , Song Zhaojie , Song Yilei , Zhang Yunfei
Published: June 2024

CO2 applications for enhanced oil recovery and storage in continental shale reservoirs are promising, and there is a need to evaluate the impact of porous structure on oil–water two-phase flow under CO2 environment. In this study, first, digital cores of quartz-rich, carbonate-rich, and clay-rich shales are established using Focused Ion Beam Scanning Electron Microscopy scanning data processed through generative adversarial networks. Subsequently, the pore networks generated by digital cores are quantitatively analyzed using the generalized extreme value distribution. Finally, pore network modeling is carried out to elucidate the effect of porous structural differences on oil–water flow considering CO2 dissolution and capillary forces. The results show that quartz-rich shale, characterized by nanopore intergranular dominance and the highest pore network connectivity, demonstrates the highest relative permeability of the oil phase. Carbonate-rich shale exhibits intermediate relative permeability of oil phase, while clay-rich shale exhibits the worst. The dissolution of CO2 reduces oil–water interfacial tension and oil viscosity, enhances oil mobilization within nanopores, and notably increases the relative permeability of the oil phase. The permeability of the oil phase is governed by pore structure, displaying positive correlations with core heterogeneity, pore radius, coordination number, and throat length, and negative correlations with throat radius.
Shallow-water waves through two new generalized multi-dimensional variable coefficient equations
Authors: Palamara Valerio , Neal Bryson , Akinyemi Lanre , Erebholo Francis , Bogale Meaza
Published: June 2024

The objective of this study is to propose and investigate two new forms of generalized variable coefficients within multi-dimensional equations describing shallow-water waves. We employ the Mathematica program to rigorously establish Painlevé's integrability for these two nonlinear equations. Subsequently, we constructed their bilinear forms and utilized Hirota's bilinear method to examine the dispersion relations and phase shifts of these two models that enable the derivative of multi-soliton solutions. Furthermore, diverse forms of lump-wave solutions are also considered. To illustrate the physical characteristics of these two models, we establish several graphical representations of the discovered solutions. These visualizations offer insights into the behavior, shape, and dynamics of both the multi-soliton, Peregrine soliton, lump wave, and rogue wave, enhancing our understanding of their physical significance. The two soliton solutions effectively replicate the shallow water waves, encompassing the T-, X-, and Y-types, along with other intricate interactions. Additionally, the lump and rogue wave structures are displayed to visually represent their spatial structures. These graphical representations offer a comprehensive view of the diverse wave phenomena observed in shallow water systems, aiding in the understanding of their spatial characteristics and interactions. Therefore, our findings indicate that the introduction of the two newly proposed integrable nonlinear evolution equations enhances the repertoire of integrable system models and aids in comprehending the distinctive characteristics of nonlinear dynamics in real-world applications.
Revisit the classical theories of the conductance of unassociated electrolytes. Is there reality in relaxation?
Authors: Kimura Keisaku
Published: June 2024

The experimental results of the ionic conductance of the electrolytic solution can be explained without the use of relaxation until almost 2M concentration of the NaCl solution within 97% agreement with two parameters: the hydrated ion radii for cations and anions. No other fitting parameters were introduced, and no ion association was assumed. The theory is based on a newly introduced electrochemical potential that incorporates the interaction between ions and fluctuations in electrolyte concentration in the nanosized region. It was found that the concept of local chemical potential, fluctuation in the nanosized area, and symmetry of the system are closely related to the Boltzmann distribution of ions. Extending the concept of a local chemical potential to the case of an external field, the derived ionic mobility automatically includes the effect of electrophoresis. The so-called electrophoretic retardation was found to be equivalent to the shielding effect of the external field. Relaxation bears a minor effect and may contribute to the ion transport of electrolytic solution at most 3%, if exists.
A parametric study of precession driven dynamos inside a sphere
Authors: Liao Zi-Ju , Su Wei-Dong
Published: June 2024

The dynamo actions of an electrically conducting fluid in a precessing sphere are investigated over a wide range of parameters by direct numerical simulation using a Galerkin spectral method. The focus of this work is to identify the most promising parameter regimes for the dynamo action and to investigate the characteristics of the magnetic field generated by precession. The influence of different nutation angles (30°,60°,90°) and different precession ratios on the ability to drive dynamo action are investigated. The optimal angle for dynamo actions is found at 90°, followed by 60° with retrograde precession. A moderate precession ratio around 0.3 is shown to be more feasible for dynamo actions. A rich set of self-sustained dynamo solutions are obtained in the parameter space we explored, including steady, periodic, quasi-periodic, and turbulent dynamos. The structure of the generated magnetic fields is analyzed by using helical wave decomposition. None of the precession driven dynamos we obtained produce a predominantly dipolar field, contrary to the convection driven dynamos. The long-time evolution of the magnetic dipole moment is investigated and different types of polarity reversals are observed.
Physical aspects of vortex-shock dynamics in delta wing configurations
Authors: Rajkumar K. , Fabbio T. Di , Tangermann E. , Klein M.
Published: June 2024

Delta wing configurations with double- and triple-leading edges introduced within the North Atlantic Treaty Organization Applied Vehicle Technology -316 task group are examined to investigate the dynamics of vortices and shocks, with potential implications for the preliminary aircraft design. The numerical simulations are conducted for the configurations at Ma∞=0.85 and Re∞=12.53×106 using the Reynolds-averaged Navier–Stokes k−ω shear stress transport (SST) model across a range of incidence angles. The detailed analysis focuses on the case with α=20° using the scale-adaptive simulation based on the k−ω SST model. This study considers shock-vortex interaction and breakdown with buffeting to study the transient flow physics over the wing. Additionally, insights into vorticity strength and destruction are gained through the enstrophy transport equation. The findings reveal that the inboard vortex (IBV) development is impeded by counter-rotating secondary vortices from IBV and the midboard vortex. A key distinction is observed for the first time between the double-delta and triple-delta wings, in that the double-delta wing experiences shock-induced vortex breakdown, with the transient nature of this breakdown leading to an adjustment in the shock position, causing a shock buffet. In contrast, the breakdown in the triple-delta wing is linked to a stationary shock induced by the kink in the planform. This study highlights the crucial role of the orientation of the shock relative to the vortex axis in characterizing the aerodynamic performance of the planforms.
Characteristics of the gas diffusion in water-bearing coal with different damage degree and its influence mechanism
Authors: Han Qijun , Shi Biming , Yue Jiwei , Sun Yongxin , Liang Yuehui , Zhang Chengcheng
Published: June 2024

The moisture content and degree of damage in water-bearing coal affect the gas diffusion characteristics in coal, which limits the effect of gas extraction. The experiments were carried out on water-bearing coal with different damage degrees using a self-built coal and gas adsorption–desorption system to study the gas diffusion characteristics of water-bearing coal with varying degrees of damage. The results show that the pore volume of tectonic coal is positively correlated with the degree of damage. The increased moisture content in coal decreases gas desorption performance, embodied in the simultaneous reduction of desorption amount, desorption speed, and diffusion coefficient. Under the same water content condition, the gas desorption amount, gas desorption rate, and gas diffusion coefficient of coal with different damage degrees all show a downward trend, and the decline range is positively correlated with the water content. The relation between the amount of gas desorption, the time, and the moisture content of the water-bearing coal with different damage degrees has been set up. The study results provide a solid theoretical foundation for evaluating and predicting the gas extraction characteristics of coal seams with varying degrees of damage.
Estimation of SARS-CoV-2 fitness gains from genomic surveillance data without prior lineage classification
Authors: Donker Tjibbe , Papathanassopoulos Alexis , Ghosh Hiren , Kociurzynski Raisa , Felder Marius , Grundmann Hajo , Reuter Sandra
Published: June 2024

The emergence of SARS-CoV-2 variants with increased fitness has had a strong impact on the epidemiology of COVID-19, with the higher effective reproduction number of the viral variants leading to new epidemic waves. Tracking such variants and their genetic signatures, using data collected through genomic surveillance, is therefore crucial for forecasting likely surges in incidence. Current methods of estimating fitness advantages of variants rely on tracking the changing proportion of a particular lineage over time, but describing successful lineages in a rapidly evolving viral population is a difficult task. We propose a method of estimating fitness gains directly from nucleotide information generated by genomic surveillance, without a priori assigning isolates to lineages from phylogenies, based solely on the abundance of single nucleotide polymorphisms (SNPs). The method is based on mapping changes in the genetic population structure over time. Changes in the abundance of SNPs associated with periods of increasing fitness allow for the unbiased discovery of new variants, thereby obviating a deliberate lineage assignment and phylogenetic inference. We conclude that the method provides a fast and reliable way to estimate fitness advantages of variants without the need for a priori assigning isolates to lineages.
Collaborative imagination synchronizes representations of the future and fosters social connection in the present
Authors: Fowler Zoë , Palombo Daniela J. , Madan Christopher R. , O’Connor Brendan Bo
Published: June 2024

From close friends to people on a first date, imagining a shared future appears fundamental to relationships. Yet, no previous research has conceptualized the act of imagination as a socially constructed process that affects how connected we feel to others. The present studies provide a framework for investigating imagination as a collaborative process in which individuals cocreate shared representations of hypothetical events—what we call collaborative imagination. Across two preregistered studies (
N
= 244), we provide evidence that collaborative imagination of a shared future fosters social connection in novel dyads—beyond imagining a shared future individually or shared experience in general. Subjective ratings and natural language processing of participants’ imagined narratives illuminate the representational features of imagined events shaped by collaborative imagination. Together, the present findings have the potential to shift how we view the structure and function of imagination with implications for better understanding interpersonal relationships and collective cognition.
A viral E3 ubiquitin ligase produced by herpes simplex virus 1 inhibits the NLRP1 inflammasome
Authors: Parameswaran Pooja , Payne Laurellee , Powers Jennifer , Rashighi Mehdi , Orzalli Megan H.
Published: June 2024

Guard proteins initiate defense mechanisms upon sensing pathogen-encoded virulence factors. Successful viral pathogens likely inhibit guard protein activity, but these interactions have been largely undefined. Here, we demonstrate that the human pathogen herpes simplex virus 1 (HSV-1) stimulates and inhibits an antiviral pathway initiated by NLRP1, a guard protein that induces inflammasome formation and pyroptotic cell death when activated. Notably, HSV-1 infection of human keratinocytes promotes posttranslational modifications to NLRP1, consistent with MAPK-dependent NLRP1 activation, but does not result in downstream inflammasome formation. We identify infected cell protein 0 (ICP0) as the critical HSV-1 protein that is necessary and sufficient for inhibition of the NLRP1 pathway. Mechanistically, ICP0’s cytoplasmic localization and function as an E3 ubiquitin ligase prevents proteasomal degradation of the auto-inhibitory NT-NLRP1 fragment, thereby preventing inflammasome formation. Further, we demonstrate that inhibiting this inflammasome is important for promoting HSV-1 replication. Thus, we have established a mechanism by which HSV-1 overcomes a guard-mediated antiviral defense strategy in humans.
High-Resolution Recognition of Orbital Angular Momentum Modes in Asymmetric Bessel Beams Assisted by Deep Learning
Authors: Xu 徐 Pengfei 鹏飞 , Tong 童 Xin 鑫 , Zeng 曾 Zishuai 子帅 , Liu 刘 Shuxi 书悉 , Zhao 赵 Daomu 道木
Published: June 2024

Fractional orbital angular momentum (OAM) vortex beams present a promising way to increase the data throughput in optical communication systems. Nevertheless, high-precision recognition of fractional OAM with different propagation distances remains a significant challenge. We develop a convolutional neural network (CNN) method to realize high-resolution recognition of OAM modalities, leveraging asymmetric Bessel beams imbued with fractional OAM. Experimental results prove that our method achieves a recognition accuracy exceeding 94.3% for OAM modes, with an interval of 0.05, and maintains a high recognition accuracy above 92% across varying propagation distances. The findings of our research will be poised to significantly contribute to the deployment of fractional OAM beams within the domain of optical communications.
Do black holes remember what they are made of?
Authors: Bandyopadhyay Harshraj , Radice David , Prakash Aviral , Dhani Arnab , Logoteta Domenico , Perego Albino , Kashyap Rahul
Published: June 2024

We study the ringdown signal of black holes formed in prompt-collapse binary neutron star mergers. We analyze data from 47 numerical relativity simulations. We show that the

(
ℓ
=
2
,
m
=
2
)

and

(
ℓ
=
2
,
m
=
1
)

multipoles of the gravitational wave signal are well fitted by decaying damped exponentials, as predicted by black-hole perturbation theory. We show that the ratio of the amplitude in the two modes depends on the progenitor binary mass ratio q and reduced tidal parameter

Λ
~

. Unfortunately, the numerical uncertainty in our data is too large to fully quantify this dependency. If confirmed, these results will enable novel tests of general relativity in the presence of matter with next-generation gravitational-wave observatories.
Superspace worldline formalism approach to quantum gravity: dimensional reduction and holography
Authors: Roux J-B
Published: June 2024

Using the ADM formalism, we demonstrate that the Hamiltonian formulation of Quantum Gravity is exactly in the form of a worldline formalism in the superspace. We then show that the Keldysh partition function reduces to the partition function of Euclidean 3D gravity. After discussing the meaning of the time parameter, we show that in the gauge fields formalism, our Keldysh partition function reduces to a generating functional of a 2D conformal field theory. This functional exhibits a minimal time-lapse proportional to the square root of the cosmological constant. From the viewpoint of the Chern–Simons/Liouville correspondence, we calculate the exchange of virtual gravitons between two massive probes from the cosmological boundary.
Application and prospect of 2D materials in photodetectors
Authors: Liu Xiangzhi , Yang Xiaozhan , Tang Qian , Lv Yue , Zhang Gang , Feng Wenlin
Published: June 2024

With the continuous development of modern information technology, higher requirements are put forward for photoelectric detection technology. Two-dimensional (2D) materials have excellent optical, electrical and mechanical properties, and easy to process and integrate, which is expected to make up for the shortcomings of traditional devices. 2D materials, which cover material systems ranging from metals, semiconductors to insulators, are one of the main material choices for new photodetectors. In recent years, great progress has been made in the preparation of 2D photoelectricity device applications. In this paper, the latest research progress of 2D materials photodetectors is summarized, including the unique physical and chemical properties of 2D materials and the key parameters of photodetector. The research progress of photodetectors based on graphene, black phosphorus and transition metal dichalcogenides is highlighted. Finally, we give an outlook on the challenges of realizing high-performance photodetectors.
Quantifying the thermal effect and methyl radical production in nanosecond repetitively pulsed glow discharges applied to a methane-air flame
Authors: M Alkhalifa Ammar , Di Sabatino Francesco , A Steinmetz Scott , Pfaff Sebastian , Huang Erxiong , H Frank Jonathan , J Kliewer Christopher , A Lacoste Deanna
Published: June 2024

In this work, we investigated non-equilibrium plasma produced by nanosecond repetitively pulsed glow discharges applied across a lean premixed methane-air flame. The flame is stationary, axisymmetric, and laminar. The discharges are applied on the symmetry axis crossing the reactant gases, flame front, and product gases, allowing phase-locked averaged measurements and comparisons with axisymmetric numerical simulations. The thermal effect and methyl radical production are quantified in the discharge in the reactant gas region. One-dimensional, two-beam, hybrid, femtosecond-picosecond, coherent anti-Stokes Raman scattering is used to acquire spatial and temporal profiles of temperature and oxygen-to-nitrogen concentration ratio. Photo-fragmentation laser-induced fluorescence is used to acquire quantitative two-dimensional profiles of methyl radicals in the discharge providing the first quantitative imaging of methyl produced ahead of a flame by plasma-induced methane dissociation. The spatial profiles of temperature and oxygen-to-nitrogen concentration ratio are in steady state, indicating that individual discharges have an insignificant heating effect. Upper and lower bounds of the produced mole fraction of methyl radicals in the plasma are obtained due to uncertainties in the collisional quenching rates of excited state methylidyne radicals in the plasma. The discharges produce a maximum of 600–1100 ppm of methyl radicals upstream of the flame front within 25 ns. This amount is similar to the predicted methyl mole fraction for the flame without plasma and thus represents a significant chemical perturbation to the reactants upstream of the flame front. The produced methyl follows an exponential decay in the first microsecond after the discharge with a decay constant of 8 µs close to the flame, and 0.8 µs further from the flame. The decay then deviates from the exponential curve and the methyl persists for tens of microseconds. The results suggest that for the tested configuration, the thermal effect of individual discharges through fast gas heating is negligible, while active chemical species are produced in large quantities in the reactant gases, upstream of the flame front.
Lagrangian particle tracking in the atmospheric surface layer
Authors: Conlin Nicholas , Even Hannah , Wei Nathaniel J , Balantrapu N Agastya , Hultmark Marcus
Published: June 2024

Field measurements in the atmospheric surface layer (ASL) are key to understanding turbulent exchanges in the atmosphere, such as fluxes of mass, water vapor, and momentum. However, current field measurement techniques are limited to single-point time series or large-scale flow field scans. Extending image-based laboratory measurement techniques to field-relevant scales is a promising route to more detailed atmospheric flow measurements, but this requires significant increases in the attainable measurement volume while keeping the spatiotemporal resolution high. Here, we present an adaptable particle tracking system using helium-filled soap bubbles, mirrorless cameras, and high-power LEDs enabling volumetric ASL field measurements. We conduct analyses pertinent to image-based field measurement systems and develop general guidelines for their design. We validate the particle tracking system in a field experiment. Single-point Eulerian velocity statistics are presented and compared to data from concurrently operated sonic anemometers. Lagrangian displacement statistics are also presented with a comparison to Taylor’s theory of dispersion. The system improves the state-of-the-art in field measurements in the lower atmosphere and enables unprecedented insights into flow in the ASL.
Research on internal leakage detection of the ball valves based on stacking ensemble learning
Authors: Shi Mingjiang , Deng Liyuan , Yang Bohan , Qin Liansheng , Gu Li
Published: June 2024

Natural gas is an important clean energy source that is mainly transported through pipelines. The ball valve is a crucial piece of control equipment for the pipeline transportation system for natural gas, and the failure of internal leakage of the ball valve will seriously affect the natural gas transmission and increase the risk of sudden safety accidents. In response to the problems of the limitations of a single machine learning model in the traditional ball valve internal leakage rate prediction methods and failure to qualitatively analyze unilateral and bilateral internal leakage recognition of ball valve, a study of ball valve internal leakage detection based on Stacking ensemble learning is proposed. A total of 15 time and frequency domain feature parameters were obtained by feature extraction of 125 and 96 sets of raw acoustic emission signals from the ball valve; the parameters of a single machine learning model were adjusted by Bayesian optimization grid search. An internal leakage rate prediction model and an internal leakage recognition model are constructed, and the proposed model is compared and analyzed with a single model through a field ball valve internal leakage test. The results indicate that the Stacking ensemble learning model outperforms each single machine learning model in terms of SMAPE (17.2583), RMSE (1.1009), and MAE (0.9375) for internal leakage rate prediction. The Stacking ensemble learning model outperformed the single machine learning model in terms of accuracy (1.0000), recall (1.0000), precision (1.0000), FAR(0), and F1-score (1.0000) for internal leakage recognition. Stacking ensemble learning significantly enhances the model’s ability to detect internal ball valve leaks.
A multi-strategy improved sparrow search algorithm for mobile robots path planning
Authors: Fan Jingkun , Qu Liangdong
Published: June 2024

Path planning for mobile robots plays a vital role in task execution, given the constraints imposed by environments and energy resources. It poses a significant challenge for mobile robots, requiring them to find a feasible path between the start point and target point that is obstacle-free and as short as possible. To address the challenge of path planning, a multi-strategy improved sparrow search algorithm with chaos operator (CMISSA) is proposed. Firstly, Tent chaos mapping and reverse learning are introduced into the population initialization of sparrow search algorithm (SSA) to enhance the uniformity and effectiveness of the initial population distribution. Secondly, adaptive parameters are applied in SSA to maintain a balance between exploitation and exploration. Thirdly, to prevent SSA from getting trapped in local optima, the chaos operator is used to perturb the population position. Finally, a novel adaptive boundary control strategy is introduced to handle the location of individuals that have crossed the boundary. In addition, the experimental results on 15 classical benchmark functions show that CMISSA has better optimization performance than other 10 comparison algorithms. Furthermore, in the path planning experimental results, the results of comparing CMISSA with 5 comparison algorithms on 5 different environments reveal CMISSA’s average path shortening rates were 34.90%, 20.11%, 29.01%, 51.97%, 37.42%, respectively. It is further demonstrated that CMISSA has superior availability for solving mobile robots path planning.
Validation and reliability of the 3D calibration evaluation algorithm for SPM
Authors: Xu Min , Hemmleb Matthias , Dai Gaoliang
Published: June 2024

Novel marker-based 3D standards, in the form of cascading step-slope pyramids, enable the calibration of three scaling factors and three coupling factors of scanning probe microscopes using only a single sample and a single measurement. They offer better convenience than conventional methods and are therefore increasingly applied. From a quality management perspective, it is of high importance to validate the evaluation algorithm of the 3D calibration strategy and analyze its error contribution. This paper proposes and develops a new software validation method based on both synthetic data and measurement data. Finally, results of our study are discussed, and the impact of the computational error on the measurement uncertainty is examined.
The mechanism of enhanced electrocatalytic water splitting on S-doped NiFe2O4/Ni–Fe alloy@copper foams
Authors: Wang Wenbin , Yang Wei , Xu Ruidong , Feng Suyang , Wang Xiaozhe
Published: June 2024

The development of bifunctional catalysts with subtle structures, high efficiencies, and good durabilities for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is crucial for overall water splitting. In this work, a multicomponent S-doped NiFe2O4/Ni–Fe micro nano flower electrocatalyst was synthesized rapidly on foam copper using a simple one-step constant current electrodeposition method. The introduction of S leads to the transformation of the microsphere structure of the Ni–Fe alloy into a cauliflower-like morphology and induces changes in the surface electronic structure, significantly enhancing the catalytic performance for the HER and OER. The S-NiFe2O4/Ni–Fe alloy/CF showed low overpotentials of 220 and 66 mV at 10 mA cm−2 in 1.0 M KOH for the OER and HER, respectively. High durability OER and HER performances were demonstrated through 60 h of chronopotentiometry and 6000 CV cycles test. Excellent overall water splitting electrocatalytic activity was observed in the S-NiFe2O4/Ni–Fe alloy/CF‖S-NiFe2O4/Ni–Fe alloy/CF two-electrode system. In particular, active-phase NiOOH, a highly active substance for OER, can be controllably formed in the reaction process owing to the nanoflower structure of multi-layer sulfur which slows down the dissolution of NiFe2O4/Ni–Fe alloy. These results suggest that this composite structure is a promising bifunctional electrocatalyst.
Laser patterned graphene pressure sensor with adjustable sensitivity in an ultrawide response range
Authors: Zhang Siyuan , Yang Chao , Qi Zhengpan , Wang Yao , Cheng E , Zhao Libin , Hu Ning
Published: June 2024

Flexible pressure sensors have attracted wide attention because of their applications in wearable electronic, human-computer interface, and healthcare. However, it is still a challenge to design a pressure sensor with adjustable sensitivity in an ultrawide response range to satisfy the requirements of different application scenarios. Here, a laser patterned graphene pressure sensor (LPGPS) is proposed with adjustable sensitivity in an ultrawide response range based on the pre-stretched kirigami structure. Due to the out-of-plane deformation of the pre-stretched kirigami structure, the sensitivity can be easily tuned by simply modifying the pre-stretched level. As a result, it exhibits a maximum sensitivity of 0.243 kPa−1, an ultrawide range up to 1600 kPa, a low detection limit (6 Pa), a short response time (42 ms), and excellent stability with high pressure of 1200 kPa over 500 cycles. Benefiting from its high sensitivity and ultrawide response range, the proposed sensor can be applied to detect physiological and kinematic signals under different pressure intensities. Additionally, taking advantage of laser programmable patterning, it can be easily configured into an array to determine the pressure distribution. Therefore, LPGPS with adjustable sensitivity in an ultrawide response range has potential application in wearable electronic devices.
Proton CT on biological phantoms for x-ray CT calibration in proton treatment planning
Authors: Fogazzi Elena , Bruzzi Mara , D’Amato Elvira , Farace Paolo , Righetto Roberto , Scaringella Monica , Scarpa Marina , Tommasino Francesco , Civinini Carlo
Published: June 2024

Objective. To present and characterize a novel method for x-ray computed tomography (xCT) calibration in proton treatment planning, based on proton CT (pCT) measurements on biological phantoms. Approach. A pCT apparatus was used to perform direct measurements of 3D stopping power relative to water (SPR) maps on stabilized, biological phantoms. Two single-energy xCT calibration curves—i.e. tissue substitutes and stoichiometric—were compared to pCT data. Moreover, a new calibration method based on these data was proposed, and verified against intra- and inter-species variability, dependence on stabilization, beam-hardening conditions, and analysis procedures. Main results. Biological phantoms were verified to be stable in time, with a dependence on temperature conditions, especially in the fat region: (−2.5 土 0.5) HU °C−1. The pCT measurements were compared with standard xCT calibrations, revealing an average SPR discrepancy within ±1.60% for both fat and muscle regions. In the bone region the xCT calibrations overestimated the pCT-measured SPR of the phantom, with a maximum discrepancy of about +3%. As a result, a new cross-calibration curve was directly extracted from the pCT data. Overall, the SPR uncertainty margin associated with this curve was below 3%; fluctuations in the uncertainty values were observed across the HU range. Cross-calibration curves obtained with phantoms made of different animal species and anatomical parts were reproducible with SPR discrepancies within 3%. Moreover, the stabilization procedure did not affect the resulting curve within a 2.2% SPR deviation. Finally, the cross-calibration curve was affected by the beam-hardening conditions on xCTs, especially in the bone region, while dependencies below 2% resulted from the image registration procedure. Significance. Our results showed that pCT measurements on biological phantoms may provide an accurate method for the verification of current xCT calibrations and may represent a tool for the implementation of a new calibration method for proton treatment planning.