bluuebunny/crossref_metadata_2025 huggingface dataset:
Geodesic tasks of global monitoring
Authors: Dimitrova A. , Samsonova N. , Shevchenko O.
Published: February 2023

The rapidly developing anthropogenic impact on the environment generates a need for a monitoring system based on aerospace methods of Earth observation. The foundation of monitoring feasibility study is cartographic materials based on aerospace information as well as traditional geodetic methods. One of the main elements of any sectoral and global monitoring system is the definition of the list of objects, with allocation of qualitative and quantitative characteristics. In the context of global monitoring, this process is performed more appropriately on the basis of remote sensing materials. In this case structural analysis of aerospace monitoring information support becomes very important. Detailed elaboration of monitoring object interpretation features allows increasing information content of cartographic materials. When interpreting boundaries of monitoring objects, the most important are plan outlines and internal structure of the researched object. Effective investigation of environmental monitoring problems on a global scale is based on integrated use of aerospace, topographic and geodetic methodology. The author's concept of classification of cartographic support for global monitoring expands the research tools for the assessment of global processes of change in the Earth's surface. The use of predictive cartographic materials in the step-by-step monitoring of global exogenous processes is the most effective tool for fixing changes in landforms.
Search for the Chiral Magnetic Wave in Pb–Pb collisions using the ALICE detector
Authors: Wu Wenya
Published: March 2023

The interplay of the chiral anomaly and the strong magnetic field (∼1015 T) created in heavy-ion collisions could give rise to a collective excitation in the quark–gluon plasma called the Chiral Magnetic Wave (CMW). This effect can be experimentally sought by the charge asymmetry (Ach) dependence of elliptic flow v2. However, non-CMW mechanisms such as local charge conservation (LCC) coupled with collective flow can also lead to a similar dependence of v2 on Ach. The triangular flow (v3) measurement serves as a reference as it is not expected to be affected by the CMW. The v2 and v3 of charged hadrons as a function of Ach measured in Pb–Pb collisions at √SNN=2.76 and 5.02 TeV are presented. In addition, the event-shape engineering (ESE) technique is adopted for the first time to quantitatively disentangle the CMW signal and the LCC background. The results indicate that the background effects dominate the CMW measurements.
Seventh and eighth-order cumulants of net-proton multiplicity distributions in heavy-ion collisions at RHIC-STAR
Authors: Pandav Ashish
Published: March 2023

We report the first measurements of seventh and eighth-order cumulants of net-proton distributions in Au+Au collisions at √SNN=27,54.4, and 200 GeV. The measurements are performed at mid-rapidity |y| < 0.5 within 0.4 < pT < 2.0 GeV/c using the Time Projection Chamber and Time-of-Flight detector. Motivation for the measurements comes from lattice-QCD and QCD based model calculations that predict their negative signs for a crossover quark-hadron transition. While 0-40% centrality measurements at √SNN=54.4 and 200 GeV are consistent with zero within large uncertainties, at √SNN=27 GeV, they are negative with ≤ 1.4σ significance. The peripheral 70-80% measurements are either positive or consistent with zero for the three energies.
Elliptic and triangular flow of (multi-)strange hadrons and ɸ mesons in BES-II energies at STAR
Authors: Liu Li-Ke
Published: March 2023

In these proceedings, we present the measurements of elliptic (v2) and triangular (v3) flow of (multi-)strange hadrons and ϕ mesons in 19.6 and 14.6 GeV Au+Au collisions from the STAR. The number of constituent quark (NCQ) scaling of v2 and v3 holds well at √SNN=19.6 GeV, which indicates the collective flow is built up in the partonic stage. At these energies, the anti-particles show better NCQ scaling than the particles for both v2 and v3, which may be caused by the different contributions from the produced and transported quarks.
Measurements of quarkonium production and polarization in Pb–Pb collisions with ALICE
Authors: Bai Xiaozhi
Published: March 2023

Quarkonia are excellent probes of deconfinement in heavy-ion collisions. For J/ψ, a bound state of cc¯ quarks, the (re-)generation is found to be the dominant production mechanism at the LHC energies. Production measurements of non-prompt J/ψ, originating from beauty-hadron decays, allow one to access the interaction of beauty-quarks with the quark-gluon plasma (QGP). Polarization and spin alignment measurements can be used to investigate the characteristics of the formed medium. Moreover, it has been hypothesized that quarkonium states can be polarized by the strong magnetic field generated in the initial state of the collision and by the large angular momentum of the medium in non-central heavy-ion collisions.

In these proceedings, the measurements of the inclusive, prompt, and non-prompt J/ψ nuclear modification factor RAA in Pb–Pb collisions at √SNN = 5.02 TeV are shown. The measured non-prompt J/ψ fraction extends down to very low pT with a significantly improved precision compared to previous publications. The results from the first publication on the J/ψ polarization with respect to the event-plane in Pb–Pb collisions at √SNN = 5.02 TeV at forward rapidity are presented as well. The results are compared with available calculations.
Results on system size dependence of strangeness production in the CERN SPS energy range from NA61/SHINE
Authors: Podlaski Piotr
Published: March 2023

NA61/SHINE is a multipurpose fixed-target facility at the CERN Super Proton Synchrotron. The main goals of the NA61/SHINE strong interactions program are to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. To reach these goals, hadron production measurements are performed in the form of a two-dimensional scan by varying collision energy and system size. The Collaboration has recently finished data acquisition for its original program on strong interactions, accumulating broad data samples on hadron production in various systems in the SPS energy range.

In this contribution, the NA61/SHINE results on identified charged kaon and pion production in p+p, Be+Be and Ar+Sc collisions at the SPS energy range (√SNN = 5.1 - 17.3 GeV) are presented. The NA61/SHINE measurements of small and intermediate-mass ion collisions establish an interesting system size dependence, showing a rapid change of hadron production properties that starts when moving from Be+Be to Ar+Sc system. In particular, Ar+Sc is the smallest system for which a significant enhancement of K+/π+ ratio with respect to p+p collisions is observed. Obtained energy and system size dependence of the measured charged hadron multiplicities are compared with available world data and various theoretical models.
Production of pions, kaons, and (anti-)protons in Au+Au collisions at √SNN = 54.4 GeV at RHIC
Authors: Gopal Krishan
Published: March 2023

We report systematic measurements of bulk properties of the system created in Au+Au collisions at √SNN = 54.4 GeV recorded by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The transverse momentum spectra of π±, K±, and p(p¯) are studied at mid-rapidity (|y| < 0.1) for different centrality classes. We also present mid-rapidity measurement of particle yields (dN/dy) and particle ratios in Au+Au collisions at √SNN = 54.4 GeV. The kinetic freeze-out parameters (Tkin and β>) are extracted from particle spectra using the blast-wave model, and all the results are compared with previously published experimental results.
Measurements on the production and properties of light hypernuclei at STAR
Authors: Ji Yuanjing
Published: March 2023

The hyperon-nucleon (Y-N) interaction, an important ingredient for the nuclear equation-of-state (EoS), remains poorly constrained. Precise measurements of hypernucei intrinsic properties and production yields in heavy-ion collisions are crucial for the understanding of their production mechanisms and the strength of the Y-N interaction. Thanks to the high statistics data taken from the STAR BES II program, a series of hypernuclei measurements are carried out at low energies. In these proceedings, we present the kinematic and centrality dependence of light hypernuclei production yields and strangeness population factor (S3, S4) in Au+Au collisions at √SNN = 3 GeV. We also report the energy dependence of Λ3H yields and S3 at mid-rapidity from 3 to 27 GeV Au+Au collisions. Precise measurements of Λ4He lifetime and Λ3H branching ratio are also reported. These results are compared with model calculations and physics implications are discussed.
Joint ATLAS/CMS ZDC upgrade project for the High Luminosity LHC
Authors: Longo Riccardo
Published: March 2023

The High Luminosity LHC (HL-LHC) provides the opportunity to study heavy ion, proton-nucleus, photon-nucleus and photon-photon collisions with unprecedented luminosities at the TeV scale. The LHC heavy ion community has mapped out an extensive range of physics measurements at the HLLHC that will push forward our understanding of both QCD, QED and even electroweak physics. The measurement of forward neutrons and photons in Zero Degree Calorimeters (ZDCs) is essential for event classification and triggering. In order to reach the required luminosities, the LHC interaction regions will be redesigned, necessitating the need to build new ZDCs that will be both narrower and much more radiation tolerant. This challenge motivated the formation of a joint project between ATLAS and CMS to build new ZDCs for Run 4, JZCaP. The ZDCs are based on radiation-hard fused silica rods that produce Cherenkov light. These rods have been developed by Heraeus Quartzglas in collaboration with JZCaP and the LHC BRAN and FLUKA groups. The Run 4 ZDCs (HL-ZDCs) are the first joint detector project between CMS and ATLAS. This talk will present the capabilities of the new ZDCs and recent R&D highlights.
Causality violations in realistic simulations of relativistic nuclear collisions
Authors: Plumberg Christopher , Almaalol Dekrayat , Dore Travis , Noronha Jorge , Noronha-Hostler Jacquelyn
Published: March 2023

We show that relativistic causality is violated in the early stages of state-of-the-art heavy-ion hydrodynamic simulations of nuclear collisions. Up to 75% of the initial fluid cells violate nonlinear causality constraints, while superluminal propagation is observed by up to 15% the speed of light. Only after 2-3 fm/c of evolution, do 50% of the fluid cells become definitely causal. Inclusion of pre-equilibrium evolution significantly reduces the number of acausal cells, but it does not eliminate them. Relativistic causality thus imposes constraints on the model parameter space of heavy-ion collision simulations.
Thermal radiation and direct photon production measurements with dielectrons in Pb–Pb and pp collisions
Authors: Murakami Hikari ,   for the ALICE Collaboration
Published: March 2023

The latest ALICE results on dielectron measurements in Pb–Pb collisions at √SNN = 5.02 TeV, and in minimum-bias (MB) and high-multiplicity (HM) pp collisions at √S = 13 TeV with LHC Run 2 data are reported. The results are compared to the predictions of dielectron yields from known hadronic sources and thermal radiation from the medium. The contribution of virtual direct photons is extracted from the data by fitting the measured invariant mass distributions. We present the direct to inclusive photon ratio, as well as the direct photon yield in both pp and central Pb–Pb collisions.
Probing neutron skin and symmetry energy with relativistic isobar collisions
Authors: Xu Hao-jie
Published: March 2023

In these proceedings, we present the three proposed observables to probe the neutron skin and symmetry energy with relativistic isobar collisions, namely, the isobar ratios of the produced hadron multiplicities (Nch), the mean transverse momenta (〈p⊥〉), and the net charge multiplicities (ΔQ). Our findings suggest potentially significant improvement to neutron skin and symmetry energy determination over traditional low energy methods.
Myocardial Evaluation in Patients with Aortic Stenosis by Cardiac Computed Tomography
Authors: Gama Francisco F. , Patel Kush , Bennett Jonathan , Aziminia Nikoo , Pugliese Francesca , Treibel Thomas
Published: March 2023

Background Aortic valve stenosis (AVS) is one of the most prevalent pathologies affecting the heart that can curtail expected survival and quality of life if not managed appropriately.

Current Status Cardiac computed tomography (CT) has long played a central role in this subset, mostly for severity assessment and for procedural planning. Although not as widely accepted as other imaging modalities for functional myocardial assessment [i. e., transthoracic echocardiogram (TTE), cardiac magnetic resonance (CMR)], this technique has recently increased its clinical application in this regard.

Future Outlook The ability to provide morphological, functional, tissue, and preprocedural information highlights the potential of the “all-in-one” concept of cardiac CT as a potential reality for the near future for AVS assessment. In this review article, we sought to analyze the current applications of cardiac CT that allow a full comprehensive evaluation of aortic valve disease.

Key Points: 

Citation Format
The Effectiveness Of Trigger Point Treatment In Chronic Pelvic Pain;
A Pilot Randomised Controlled Trial
Authors: Atas Kubra , Mutlu Ebru Kaya , Yasa Cenk , Ugurlucan Funda Gungor
Published: March 2023

Objective To investigate the effectiveness of ischemic compression and
low-level laser therapy methods combined with exercise on the myofascial trigger
points in women with Chronic Pelvic Pain and to determine which method is more
effective.

Methods It was a parallel designed, single-blind pilot randomized clinical
trial. Patients were recruited at physiotherapy laboratory of the Istanbul
University from September 2017 to June 2019. Twenty-eight women patients with
Chronic Pelvic Pain were included into the trial. Patients were randomized into
two groups. Group 1 received ischemic compression and Group 2 received low-level
laser therapy twice a week for 6 weeks. Both groups received the same standard
exercise program. Pain, range of motion, pelvic floor symptom severity, quality
of life, satisfaction, anxiety, and depression were assessed after 6 weeks, and
1-year follow up.

Results Following the treatment, significant differences were observed
within both group subjects in pain, range of motion, symptom severity, quality
of life, and anxiety-depression (p<0.05). This significant improvement
in pain, symptom severity, symptoms related quality of life and pain subgroup of
Short Form 36, continued after 1-year follow up (p<0.05). In comparison
between group, Group 1 have more significant improvement than Group 2 in terms
of symptoms related quality of life (p<0.05).

Conclusion Both methods have shown efficacy and can be used safely in
chronic pelvic pain patients. Because it is more effective on symptoms related
quality of life, the ıschemic compression method may be preferred for
primary use.
Nachruf auf
Frau Dr. Christa Maar
Authors: Birkner Berndt
Published: March 2023

Der Name Christa Maar ist in Deutschland auf das engste verbunden mit der
Darmkrebsfrüherkennung. Frau Dr. Maar, die sich als Kunsthistorikerin
promovierte, wurde durch das Schicksal ihres einzigen Sohnes Felix, der 2001 an
einem Darmtumor starb, zu einer profunden Kennerin der medizinischen
Prävention.
Radiologic Evolution after Scapholunate Dorsal Capsulodesis for Chronic Tears
Authors: Borrel François , Gras Mathilde , Arnaout Ahlam , Mathoulin Christophe , Merlini Lorenzo
Published: March 2023

Background Many debates are still ongoing for the management of chronic scapholunate (SL) injuries. We have proposed an arthroscopic technique of dorsal capsulodesis with good clinical results. We now propose a radiological follow-up.

Purpose To determine if arthroscopic dorsal capsulodesis can improve the radiographic SL angle and maintain this correction over time.

Methods From January 2020 to January 2021, we included every patient with an SL instability and sorted them according to the European Wrist Arthroscopy Society (EWAS) classification. All patients had bilateral X-rays with a measurement of the radiolunate (RL) and SL angles for both the pathologic and healthy side. We also included patients with lunotriquetral or triangular fibrocartilage complex lesions. The exclusion criteria were the presence of arthritis and persistent intraoperative SL instability after capsulodesis. An arthroscopic dorsal capsulodesis was performed in all patients as originally described by Mathoulin. The RL and SL angles were then again measured on the immediate postoperative X-ray, and then again at 3, 6, and 12 months postoperatively. The statistical analysis was done using a paired Student's t-test with 145 degrees of freedom and α = 0.05.

Results We included a total of 146 patients with a 1-year follow-up. Both the RL angle and the SL angles approach the healthy side at 12 months postoperatively. The RL angle has increased from −7.23 degrees to 4.37 degrees; the difference is still statistically significative, but it is almost equal to the healthy side (5.16 degrees). The SL angle has lowered from 74.55 to 54.95; the difference is still statistically and radiologically significative (6.788 degrees) but has been lowered by 74.3%.

Conclusion This study shows that this technique can normalize the dorsal intercalated segment instability (DISI) over time without the need for any pinning or invasive ligament reconstructive surgery.

Level of Evidence Level IV, cohort study.

Clinical Relevance Dorsal capsulodesis should be considered in all reducible SL injuries, even when DISI is present.
Tunneling from general Smith–Volterra–Cantor potential
Authors: Narayan Singh Vibhav , Umar Mohammad , Hasan Mohammad , Prasad Mandal Bhabani
Published: March 2023

We study the tunneling problem from the general Smith–Volterra–Cantor (SVC) potential of finite length L characterized by the scaling parameter ρ and stage G. We show that the SVC(ρ) potential of stage G is a special case of the super periodic potential (SPP) of order G. By using the SPP formalism developed by us earlier, we provide the closed form expression of the tunneling probability TG(k) with the help of the q-Pochhammer symbol. The profile of TG(k) with wave vector k is found to saturate with increasing stage G. Very sharp transmission resonances are found to occur in this system, which may find applications in the design of sharp transmission filters.
Deceleration of ion and plasma flows in Hall-effect electrostatic systems
Authors: Melnikov Andrey , Obukhov Vladimir
Published: March 2023

The paper presents the results of a theoretical and experimental study of the deceleration of ion and plasma flows in ion decelerators operating on the basis of an E→×B→ discharge with the Hall effect. For quantitative computational analysis of the deceleration process, an analytical model of the electric deceleration layer (E-layer) is proposed; it is based on a diffusion model of a discharge with closed electron drift, in the approximation of classical electron mobility transverse to the magnetic field, taking into account the electron current escape out of the ion beam region. Estimated dependences of the E-layer parameters and the efficiency of ion kinetic energy conversion into electrical energy on the parameters of the incident ion flow are given. The experimental results on the deceleration of plasma and ion flows with the xenon ion energy from 0.15 to 2 keV and ion current density in the range of 1–30 A/m2 are presented. The E-layer properties such as its thickness, the efficiency of the ion kinetic energy conversion into electrical energy, and the layer position in the deceleration channel were determined by test. We studied the effect of partial closure of the electron drift current in the deceleration channel outside the plasma flow volume on the efficiency of energy conversion. The study results can be used to build a detailed phenomenological pattern of plasma flow deceleration in devices with an E→×B → discharge with the Hall effect and to assess the possibility of developing various ion decelerators.
Magnetization dynamics of a CoFe/Co2MnSi magnetic bilayer structure
Authors: Kim Sujung , Guo Yawen , Yang Weigang , Joshi Toyanath , Lederman David , Schmidt Holger
Published: March 2023

Half-metallic Heusler alloys are receiving significant attention for spintronic applications utilizing magnetic tunnel junctions and requiring large spin polarization. Co2MnSi (CMS) is one of the most promising candidates for this purpose. Here, we report the magnetization dynamics of a thin, epitaxial CMS film in a magnetic CoFe/CMS bilayer structure sputtered on an MgO substrate. The magnetic precession frequency response of the CoFe/CMS bilayer shows a fourfold symmetry with respect to the azimuthal applied field angle, reflecting the crystal symmetry of the CMS layer and not the underlying CoFe film. Moreover, the effective Gilbert damping parameter exhibits inhomogeneous broadening at lower applied magnetic fields. At large fields, however, the azimuthal angle dependence disappears, and the intrinsic Gilbert damping is observed. This study provides insight into the dynamics of a magnetic bilayer structure that forms an integral element in spintronic applications.
Synthesis and characterization of bismuth ferrite particles using a nano-agitator bead mill
Authors: Smith Lyndon , Shield Jeffrey , Ahmadi Zahra , Jeelani Shaik , Rangari Vijaya
Published: March 2023

Bismuth ferrite (BiFeO3) nanocomposites were synthesized using a novel nano-agitator bead milling method followed by calcination. Bismuth oxide and iron oxide nanoparticles were mixed in a stoichiometric ratio and milled for 3 h and calcined at 650 °C in air. X-ray diffraction with Rietveld refinement, scanning electron microscopy, and transmission electron microscopy techniques were used to elucidate the structure of BiFeO3. The particle diameter was found to be ∼17 nm. Magnetic and electrical measurements were performed, and these results were compared with those of similar methods. Mostly, BiFeO3 was obtained with minor secondary phase formation. The resulting powder was weakly ferromagnetic with a remnant magnetization of 0.078 emu/g. This can be attributed to residual strain and defects introduced during the milling process. Electrical testing revealed a high leakage current density that is typical of undoped bismuth ferrite.
3D particle-in-cell study of the electron drift instability in a Hall Thruster using unstructured grids
Authors: Villafana W. , Cuenot B. , Vermorel O.
Published: March 2023

In a Hall Thruster, the E×B current generates a strong electron drift with respect to the ions, which can trigger plasma instabilities, such as the electron drift instability (EDI), also called the electron cyclotron drift instability. The EDI has drawn a great deal of attention in the E×B community as previous one- and two-dimensional Particle-In-Cell (PIC) studies suggest it plays a major role in the anomalous transport of electrons across the magnetic barrier. However, experiments showed that the EDI has an inherent three-dimensional nature, which cannot be accurately described in a 1D or 2D configuration. Unfortunately, due to their prohibitive computational cost, needed 3D PIC simulations remained inaccessible without scaling plasma parameters, which inevitably modified the physics in a Hall Thruster. Thanks to recent computational developments, this paper presents a 3D fully kinetic investigation of the EDI in a typical Hall Thruster channel and near plume region. The study was conducted using an unstructured grid, thus demonstrating the feasibility to model more complicated geometries in the future. The growth and development of the EDI are described along with other plasma fluctuations, possibly the signature of another plasma instability, the modified-two-stream-instability. 3D effects on the anomalous transport are also assessed and found to be lower than in an analogous 2D simulation. This is due to lower losses in 2D, which lead to the saturation of the EDI occurring at higher energy levels.
An optimization-based algorithm for obtaining an optimal synchronizable network after link addition or reduction
Authors: Parastesh Fatemeh , Sriram Sridevi , Natiq Hayder , Rajagopal Karthikeyan , Jafari Sajad
Published: March 2023

Achieving a network structure with optimal synchronization is essential in many applications. This paper proposes an optimization algorithm for constructing a network with optimal synchronization. The introduced algorithm is based on the eigenvalues of the connectivity matrix. The performance of the proposed algorithm is compared with random link addition and a method based on the eigenvector centrality. It is shown that the proposed algorithm has a better synchronization ability than the other methods and also the scale-free and small-world networks with the same number of nodes and links. The proposed algorithm can also be applied for link reduction while less disturbing its synchronization. The effectiveness of the algorithm is compared with four other link reduction methods. The results represent that the proposed algorithm is the most appropriate method for preserving synchronization.
Dirac field in AdS2 and representations of SL̃(2,R)
Authors: Serrano Blanco David
Published: March 2023

We analyze a massive spinor field satisfying the Dirac equation in the universal covering space of two-dimensional anti-de Sitter space. In order to obtain well-defined dynamics for the classical field despite the lack of global-hyperbolicity of the spacetime, we impose a suitable set of boundary conditions that render the spatial component of the Dirac operator self-adjoint. Then, we find which of the solution spaces obtained by imposing the self-adjoint boundary conditions are invariant under the action of the isometry group of the spacetime manifold, namely, the universal covering group of SL(2,R). The invariant solution spaces are then identified with unitary irreducible representations of this group using the classification given by Pukánszky [Math. Ann. 156, 96–143 (1964)]. We determine which of these correspond to invariant positive- or negative-frequency subspaces and, thus, result in a vacuum state invariant under the isometry group after canonical quantization. Additionally, we examine the invariant theories obtained from the self-adjoint boundary conditions, which result in a non-invariant vacuum state, identifying the unitary representation this state belongs to.
A novel architecture for room temperature microwave optomechanical experiments
Authors: Kumar Sumit , Spence Sebastian , Perrett Simon , Tahir Zaynab , Singh Angadjit , Qi Chichi , Perez Vizan Sara , Rojas Xavier
Published: March 2023

We have developed a novel architecture for room temperature microwave cavity optomechanics, which is based on the coupling of a 3D microwave re-entrant cavity to a compliant membrane. Device parameters have enabled resolving the thermomechanical motion of the membrane and observing optomechanically induced transparency/absorption in the linear regime for the first time in a microwave optomechanical system operated at room temperature. We have extracted the single-photon coupling rate (g0) using four independent measurement techniques and, hence, obtained a full characterization of the proposed cavity optomechanical system.
First self-consistent simulations of trapped electron clouds in a gyrotron gun and comparison with experiments
Authors: Le Bars G. , Loizu J. , Hogge J.-Ph. , Alberti S. , Romano F. , Genoud J. , Pagonakis I. G.
Published: March 2023

We report on the initial validation of the novel code FENNECS, which simulates the spontaneous formation of trapped electron clouds in coaxial geometries with strong externally applied azimuthal flows and in the presence of a residual neutral gas. For this purpose, a realistic gyrotron electron gun geometry is used in the code, and a self-consistent electron cloud build-up is simulated. The predicted electronic current resulting from these clouds that is collected on the gun electrodes is simulated and successfully compared with the previous experimental results for configurations with different externally applied electric and magnetic fields. These different configurations effectively modify the size and depth of the trapping potential wells responsible for the confinement of the electron clouds. This investigation also provides further insight into the link between potential well depth and resulting electronic current.
Determining the impact of gold nanoparticles on amyloid aggregation with 2D IR spectroscopy
Authors: Hess Kayla A. , Spear Nathan J. , Vogelsang Sophia A. , Macdonald Janet E. , Buchanan Lauren E.
Published: March 2023

As nanomaterials become more prevalent in both industry and medicine, it is crucial to fully understand their health risks. One area of concern is the interaction of nanoparticles with proteins, including their ability to modulate the uncontrolled aggregation of amyloid proteins associated with diseases, such as Alzheimer’s disease and type II diabetes, and potentially extend the lifetime of cytotoxic soluble oligomers. This work demonstrates that two-dimensional infrared spectroscopy and 13C18O isotope labeling can be used to follow the aggregation of human islet amyloid polypeptide (hIAPP) in the presence of gold nanoparticles (AuNPs) with single-residue structural resolution. 60 nm AuNPs were found to inhibit hIAPP, tripling the aggregation time. Furthermore, calculating the actual transition dipole strength of the backbone amide I’ mode reveals that hIAPP forms a more ordered aggregate structure in the presence of AuNPs. Ultimately, such studies can provide insight into how mechanisms of amyloid aggregation are altered in the presence of nanoparticles, furthering our understanding of protein–nanoparticle interactions.
Unusual mechanical strengths of Ta2O5 stable phases: A first-principles calculation study
Authors: He Yuxi , Sun Hong
Published: March 2023

Tantalum, in its most stable Ta2O5 oxide form, has long been recognized as a superior coating material in orthopedic applications. In this study, the ideal mechanical strengths of I41/amd, Cmmm, C2/c, Pm, and Pbam phases of Ta2O5 are investigated from first-principles calculation, where the stress–strain curves under various deformation strains are obtained and the structural evolution in terms of atomic bonding is analyzed. The results reveal that these stable Ta2O5 polymorphs show unusual mechanical strengths on their high symmetric crystalline planes. Shear super-plasticity is found on the (001) crystalline plane of the I41/amd phase in any shear direction. Shear strain-stiffening exists on the (100) crystalline plane of the Pm phase in the shear direction within an angle of ±18° along the [001] direction. Both shear super-plasticity and shear strain-stiffening make these crystalline planes be able to sustain excessively large shear deformations. Large and isotropic shear strengths are predicted on the (010) crystalline planes of Pm and Pbam phases with nearly identical maximum and minimum peak shear stresses approaching 15 GPa. Much stronger compression and tensile strengths are obtained normal to the (010) crystalline plane of the C2/c phase due to its special spring-like bonding structure, which can endure the compression deformation up to 30%. These findings provide guidance for selecting suitable phases of Ta2O5 and growth directions with crystalline planes possessing excellent mechanical properties in applications of Ta2O5 as a coating material on Ti alloys for biomedical replacements of damaged human organs, such as hip joints, dental implants, and artificial hearts.
Precessing cylinder as high-shear-rate mixer: Application to emulsification
Authors: Goto Susumu , Horimoto Yasufumi , Kaneko Takuro , Oya Kohei , Sugitani Yuji , Aritsu Shota , Yoshida Masato , Ohyama Haruka , Eguchi Kento , Kukimoto Shota , Matsuyama Kazuo , Nishimura Toru , Fukuda Kimikazu , Onoda Keiichi
Published: March 2023

Through laboratory experiments of oil-in-water emulsification, we show that we can construct a high-shear-rate mixer (precession mixer) by using the precession of a cylindrical container without any mixing blades. For high-shear-rate mixing, a container with a larger diameter and its faster spin are preferable so that the wall velocity becomes large enough. Then, emulsification is most efficient when we set the Poincaré number Po=Ωp/Ωs, which is the ratio of the spin and precession rotation speeds, about 0.2–0.3. When Po is smaller than these values, shear rates in the mixer get much lower, though mixing in the bulk of the container is enhanced. On the other hand, when Po is larger, shear rates near the cylindrical wall get higher but mixing in the bulk drastically declines. Through our systematic parameter survey for efficient emulsification by the precession mixer, we have also discovered an experimental law describing the maximum shear rate in the mixer. Since we can use it to appropriately choose the driving conditions of the mixer according to the properties of the materials to be mixed, this experimental law gives useful information for the practical use of the mixer.
Resonance control method to suppress the self and mutual inductances of a 3-phase magnetic navigation system for fast drilling motion of micro helical robots
Authors: Kwon J. , Sa J. , Lee D. , Jang G.
Published: March 2023

We developed a resonance control method to generate a high-speed rotating magnetic field in a three-phase magnetic navigation system composed of three electromagnets. The proposed resonance control method calculates the amplitudes and phases of voltages, while the capacitances suppressing the self and mutual inductances of the electromagnets to keep the currents and the magnitude of the rotating magnetic field constant, even if the frequency of the rotating magnetic field increases. Finally, we prototyped the three-phase magnetic navigation system and the variable capacitor module to validate the effectiveness of the proposed resonance control method experimentally.
Ionocaloric refrigeration makes its debut
Authors: Wilson R. Mark
Published: March 2023

Adding salt to a material lowers its melting point and removes heat. New work describes how to make that process reversible and cyclic.
Splitting atoms together
Authors: Kleemans Machiel , Wilschut Hans
Published: March 2023

Despite the US’s strict postwar limitations on sharing nuclear knowledge, Norway and the Netherlands together were able to build a nuclear reactor several years after World War II ended.
Fine-grained transfer learning based on deep feature decomposition for rotating equipment fault diagnosis
Authors: Dong Jingchuan , Su Depeng , Gao Yubo , Wu Xiaoxin , Jiang Hongyu , Chen Tao
Published: March 2023

The study of transfer learning in rotating equipment fault diagnosis helps overcome the problem of low sample marker data and accelerates the practical application of diagnostic algorithms. Previously reported methods still require numerous fault data samples; however, it is unrealistic to obtain information about the different health states of rotating equipment under all operating conditions. In this paper, a two-stage, fine-grained, fault diagnosis framework is proposed for implementing fault diagnosis across domains of rotating equipment under the condition of no target domain data. Considering that the target domain is completely unknown, the main idea of this paper is to decompose multiple source domain depth features to identify domain-invariant categorical features common under different source domains and classify unknown target domains. More impressively, the problems of data imbalance and low signal-to-noise ratio can be properly solved in our network. Extensive experiments are conducted in two different case studies of rotating devices to validate the proposed method. The experiments show that the method in this paper achieves significant results on both bearing and gearbox health status classification tasks, outperforming other deep transfer learning methods.
Hydrogenated cove-edge aluminum nitride nanoribbons for ultrascaled resonant tunneling diode applications: a computational DFT study
Authors: Kharwar Saurabh , Singh Sangeeta , Kaushik Brajesh Kumar
Published: March 2023

While synthesizing quasi-one-dimensional nanoribbons, there is a finite probability that edges have cove-edge defects. This paper focuses on the structural, electronic, and transport properties of cove-edge aluminum nitride nanoribbons (AlNNR) using density functional theory and the non-equilibrium Green’s function (NEGF) method. The cove-edge AlNNRs are thermodynamically stable and exhibit metallic behavior. Interestingly, the calculated current–voltage characteristics of the cove-edge AlNNR-based nanodevices show negative differential resistance (NDR). The H-AlN-Cove nanodevice exhibits high peak-to-valley current ratio (PVCR) of the order of 107. The calculated PVCR of the H-AlN-Cove nanodevice is 106 times higher than that of the silicene nanoribbon (SiNR) and graphene nanoribbon (GNR), and 104 times higher than that of the phosphorene nanoribbon (PNR) and arsenene nanoribbons (ANR)-based devices respectively. The NDR feature with high PVCR provides a prospect for the cove-edge AlNNR in nanodevice applications.
CuSCN/Si heterojunction near-infrared photodetector based on micro/nano light-trapping structure
Authors: Liu Biao , Shen Honglie , Zhang Jingzhe , Chen Dewen , Mao Weibiao
Published: March 2023

In this paper, high-performance CuSCN/Si heterojunction near-infrared photodetectors were successfully prepared using nanoscale light-trapping optical structures. Various light-trapping structures of ortho-pyramids, inverted pyramids and silicon nanowires were prepared on silicon substrates. Then, CuSCN films were spin-coated on silicon substrates with high crystalline properties for the assembly of CuSCN/Si photodetectors. Their reflectance spectra and interfacial passivation properties were characterized, demonstrating their superiority of light-trapping structures in high light response. Under the irradiation of 980 nm near-infrared light, a maximum responsivity of 2.88 A W−1 at −4 V bias and a specific detectivity of 5.427 × 1010 Jones were obtained in the CuSCN/Si heterojunction photodetectors prepared on planner silicon due to 3.6 eV band gap of CuSCN. The substrates of the light-trapping structure were then applied to the CuSCN/Si heterojunction photodetectors. A maximum responsivity of 10.16 A W−1 and a maximum specific detectivity of 1.001 × 1011 Jones were achieved under the 980 nm near-infrared light irradiation and −4 V bias, demonstrating the advanced performance of CuSCN/Si heterojunction photodetectors with micro-nano light-trapping substrates in the field of near-infrared photodetection compared to other silicon-based photodetectors.
Ferromagnetic and metamagnetic transitions in itinerant electron systems: a microscopic study
Authors: Yamase Hiroyuki
Published: March 2023

We perform a microscopic study of itinerant ferromagnetic systems. We reveal a very rich phase diagram in the three-dimensional space spanned by the chemical potential, a magnetic field, and temperature beyond the Landau theory analyzed so far. Besides a generic wing structure near a tricritical point upon introducing the magnetic field, we find that an additional wing can be generated close to a quantum critical end point (QCEP) and also even from deeply inside the ferromagnetic phase. A tilting of the wing controls the entropy jump associated with the metamagnetic transition. Ferromagnetic and metamagnetic transitions are usually accompanied by a Lifshitz transition at low temperatures, i.e. a change of Fermi surface topology including the disappearance of the Fermi surface. In particular, the Fermi surface of either spin band vanishes at the QCEP. These rich phase diagrams are understood in terms of the density of states and the breaking of particle-hole symmetry in the presence of a next nearest-neighbor-hopping integral tʹ, which is expected in actual materials. The obtained phase diagrams are discussed in a possible connection to itinerant ferromagnetic systems such as UGe2, UCoAl, ZrZn2, and others including materials exhibiting the magnetocaloric effect.
Observational constraints on warm natural inflation
Authors: Montefalcone Gabriele , Aragam Vikas , Visinelli Luca , Freese Katherine
Published: March 2023

Warm natural inflation is studied for the case of the original cosine potential. The
radiation bath during inflation induces a dissipation (friction) rate in the equation of motion
for the inflaton field, which can potentially reduce the field excursion needed for an
observationally viable period of inflation. We examine if the dissipation thus provides a
mechanism to avoid the large decay constant f ≳ M
pl of cold cosine natural
inflation. Whereas temperature independent dissipation has previously been shown to alleviate the
need for a trans-Planckian decay constant f, we illustrate here the difficulties of
accommodating a significantly sub-Planckian decay constant (f < 10-1
M
pl) for the
case of a temperature dependent dissipation rate in the form Γ ∝ Tc
, with
 c = {1,3}. Such dissipation rates represent physically well-motivated constructions in the
literature. For each model, we map its location in the r-ns
plane and compare with cosmic
microwave background (CMB) data. For c = 1 (c = 3), we find that agreement with CMB data requires
that dissipation be in the weak (moderate) regime and that the minimum allowed value of the decay
constant in the potential is f
min = 0.3 (0.8) M
pl, respectively.
Extraction energy from charged Vaidya black hole via the Penrose process
Authors: Vertogradov Vitalii
Published: March 2023

In this paper, we consider the analogy of the Penrose process in charged Vaidya spacetime. We calculate the border of the generalized ergosphere, in which the charged particles with negative energy might exist, and show that it is temporary. We show that there are no closed orbits for particles with negative energy inside the generalized ergosphere. We investigate the question about the efficiency of the Penrose process and show that one cannot extract large energies from a black hole if the velocities of ingoing and outgoing particles are of the same order. In the case of the extremal black hole, we show that the upper limit is restricted by the absolute value of the electric charge per mass.
Mass spectra of doubly heavy tetraquarks in diquark−antidiquark picture*
Authors: Song Yong-Xing , Jia Duo-Jie
Published: March 2023

Inspired by the recent observation of the first doubly charmed tetraquark T

cc
, we apply the linear Regge relation and mass scaling to study low-lying mass spectra of the doubly heavy tetraquark in a heavy-diquark−light-antidiquark picture. The measured data and other compatible estimates of ground-state masses of doubly heavy baryons are employed to evaluate masses of heavy diquark M

QQ
(Q = c, b) and the D/D

s
meson masses are used in mass scaling to determine the hyperfine mass splitting. Our mass computation indicates that all low-lying states of doubly heavy tetraquarks are unstable against strong decays to two heavy-light mesons, except for the ground states of nonstrange bb tetraquarks.
Development and application of absorbed dose primary standard for 60Co and high-energy photon beams using water calorimetry
Authors: Wang Zhipeng , Wang Kun , Jin Sunjun , Wang Feifei , Zhang Xi , Liu Fubin , Yao Jintao , Huang Ji , Qi Yaping , Zhang Jian
Published: March 2023

Several new glass vessels, thermistor probes, and water phantoms have been designed and built at the National Institute of Metrology (China) to upgrade and develop the existing water calorimeter. The increased plane-parallel vessels have shorter thermal stability times and shallower positioning depths (∼1.3 cm) than the previous cylindrical vessels, which makes them suitable for electron beams. The sensitivity of the new probes is 10% greater than the previous ones. In this study, detailed experimental and theoretical investigations of various factors affecting the new water calorimeter are performed. The system uncertainty of the water calorimeter is reduced and the robustness of the determination of the absorbed-dose-to-water D
w is improved using a variety of geometric detector vessels and two kinds of high-purity water systems saturated with high-purity gases. This new calorimeter is employed as a primary standard for determining the D
w, has achieved a combined standard uncertainty of 0.24% for a 60Co beam, 0.27% for 6 MV and 10 MV photon beams and 0.30% for a 25 MV photon beam. The beam quality conversion factors kQ
of ten cylindrical and three plane-parallel ionization chambers are measured using the new calorimeter to improve the reference dosimetry accuracy of high-energy clinical photon beams.
Collaborative Planning Model of PV-Battery Storage System for Microgrid Considering Demand Response
Authors: Shen Weijie , Zeng Ming
Published: March 2023

The configuration of energy storage with reasonable capacity in the photovoltaic microgrid is a powerful way to promote the local consumption of distributed photovoltaic and improve the efficiency of photovoltaic system. DSM can effectively reduce grid investment and become an important regulation means for efficient operation of power system. The main innovation of this research is to consider the utilization of demand side resources in microgrid planning, which is rarely deployed in previous studies. Firstly, the models of renewable energy output characteristics and energy storage SOC characteristics are established, and the demand response mechanism is analysed; Secondly, taking the minimization of the comprehensive cost of the system as the objective function and the energy balance, equipment characteristics as constraints, a collaborative planning model of PV-Battery storage system for microgrid considering demand response is constructed. Finally, the rationality and effectiveness of the proposed optimization model are verified by the actual data of a microgrid in Fuzhou.
Metric Mutation Anomaly Detection Method of the Power Grid Dispatching Automatic System Based on Machine Learning and Statistics
Authors: Huang Xinjian , Zhai Mingyu , Gao Shang , Ji Kun , Li Hao , Zhang Pan
Published: March 2023

With the increase of the scale, function and complexity of power grid dispatching automatic system, the difficulty of system operation and maintenance increases significantly. This paper presents a metric mutation anomaly detection method based on the combination of machine learning and statistical algorithm. First, the system data is smoothed by machine learning algorithm, and the difference between the smoothed value and the real value is calculated. Then, the difference was used to detect data anomaly by ensemble of statistical method. The effectiveness and accuracy of the method is verified by the test data of the power grid dispatching automatic system. The method can quickly locate the anomaly components of the system and assist the system maintenance personnel in making decisions.