bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of N-tosylaziridines from substituted alkenes via zirconooxaziridine catalysis
Authors: Pinarci Ali A. , Daniecki Noah , TenHoeve Tyler M. , Dellosso Brandon , Madiu Rufai , Mejia Liliana , Bektas Seda E. , Moura-Letts Gustavo
Published: March 2022

Novel zirconooxaziridine complex for the catalytic and highly stereospecific aziridination of unactivated alkenes.
Transition structures for the oxy–ene reaction
Authors: Yang Shengwen , Miaskiewicz Solène , Bour Christophe , Alix Aurélien , Gandon Vincent
Published: March 2022

Can this occur naturally? This study offers the theoretical background of an overlooked pericyclic reaction.
Structural, dynamical, and electronic properties of the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide
Authors: Ishisone Kana , Ori Guido , Boero Mauro
Published: March 2022

A first-principles dynamical study of the ionic liquid EMIM-TFSI with cutting-edge time and size scale modeling provides a thorough investigation of the structural, dynamical, electronic, bonding and dielectric properties of the material.
Fluorescence sensing by carbon nanoparticles
Authors: Santonocito Rossella , Intravaia Manuelamaria , Caruso Ivana Maria , Pappalardo Andrea , Trusso Sfrazzetto Giuseppe , Tuccitto Nunzio
Published: March 2022

Herein, a summary of the fluorescent sensing applications of carbon nanoparticles for the detection of chemicals and ions is reported.
Assembly of gold nanorods functionalized by zirconium-based metal–organic frameworks for surface enhanced Raman scattering
Authors: Li Juan , Liu Zhenfeng , Tian Dehua , Li Baojun , Shao Lei , Lou Zaizhu
Published: March 2022

Assembly of gold nanorods functionalized by zirconium-based metal–organic frameworks (Au nanorod@Zr-MOF) for superior SERS detection.
A bioinspired solar evaporator with a horizontal channel-like framework for efficient and stable high-salinity brine desalination
Authors: Zhang Shuqian , Wei Han , Zhang Zhijian , Zhang Jianzhong , Bao Hua , Zhang Wang
Published: March 2022

Bioinspired solar evaporators simultaneously exhibited high evaporation efficiency and salt resistance due to their unique horizontal channel-like framework.
Dearomative [4 + 3] cycloaddition of furans with vinyl-N-triftosylhydrazones by silver catalysis: stereoselective access to oxa-bridged seven-membered bicycles
Authors: Liu Zhaohong , Yang Yong , Jiang Xinyu , Song Qingmin , Zanoni Giuseppe , Liu Shaopeng , Bi Xihe
Published: March 2022

A practical dearomative [4 + 3] cycloaddition of furans with vinylcarbenes to access oxa-bridged seven-membered carbocycles, with complete and predictable stereoselectivity, is achieved by merging silver catalysis and vinyl-N-triftosylhydrazones.
Acetylene containing 2-(2-hydrazinyl)thiazole derivatives: design, synthesis, andin vitroandin silicoevaluation of antimycobacterial activity againstMycobacterium tuberculosis
Authors: Maganti Lakshmi Haritha Bharathi , Ramesh Deepthi , Vijayakumar Balaji Gowrivel , Khan Mohd Imran K. , Dhayalan Arunkumar , Kamalraja Jayabal , Kannan Tharanikkarasu
Published: March 2022

In an attempt to find novel anti-mycobacterial agents, novel acetylene containing 2-(2-hydrazinyl)thiazole derivatives have been synthesized and evaluated againstMycobacterium tuberculosis.
A two-photon ratiometric fluorescent probe for real-time imaging and quantification of NO in neural stem cells during activation regulation
Authors: Liang Mengyu , Liu Zhichao , Zhang Zhonghui , Mei Yuxiao , Tian Yang
Published: March 2022

Developing a novel tool capable of real-time monitoring and accurate quantification of NO is critical to understanding its role in physiological and pathological processes.
Graphitic-N-doped graphene quantum dots for photothermal eradication of multidrug-resistant bacteria in the second near-infrared window
Authors: Geng Bijiang , Li Yuan , Hu Jinyan , Chen Yuanyuan , Huang Junyi , Shen Longxiang , Pan Dengyu , Li Ping
Published: March 2022

The synthesis procedures of graphitic-N-doped graphene quantum dots (GQDs) and their applications for photothermal eradication of MDR bacterial infection in the second near-infrared window.
Spatial sequestration of misfolded proteins in neurodegenerative diseases
Authors: Rolli Sarah , Sontag Emily Mitchell
Published: March 2022

Properly folded, functional proteins are essential for cell health. Cells sustain protein homeostasis, or proteostasis, via protein quality control (PQC) mechanisms. It is currently hypothesized that a breakdown in proteostasis during ageing leads to the accumulation of protein aggregates in the cell and disease. Sequestration of misfolded proteins into PQC compartments represents one branch of the PQC network. In neurodegenerative diseases, certain proteins form abnormal protein deposits. Which PQC compartments house misfolded proteins associated with neurodegenerative diseases is still being investigated. It remains unclear if sequestration of these misfolded proteins is toxic or protective to the cell. Here, we review the current knowledge on various PQC compartments that form in the cell, the kinds of protein aggregates found in neurodegenerative diseases, and what is known about their sequestration. Understanding how protein sequestration occurs can shed light on why aggregates are toxic to the cell and are linked to neurodegenerative diseases like Huntington's, Alzheimer's, and Parkinson's diseases.
The MURALES survey
Authors: Balmaverde B. , Capetti A. , Baldi R. D. , Baum S. , Chiaberge M. , Gilli R. , Jimenez-Gallardo A. , Marconi A. , Massaro F. , Meyer E. , O’Dea C. , Speranza G. , Torresi E. , Venturi G.
Published: March 2022

This is the sixth paper presenting the results of the MUse RAdio Loud Emission line Snapshot survey. We observed 37 radio sources from the 3C sample with z < 0.3 and a declination < 20° with the Multi Unit Spectroscopic Explorer optical integral field spectrograph at the Very Large Telescope. Here, we focus on the properties of the extended emission line regions (EELRs) that can be studied with unprecedented detail thanks to the depth of these observations. Line emission in the ten FR Is is, in most cases, confined to within ≲4kpc, while large-scale (≳4 kpc) ionized gas is seen in all but two of the 26 FR IIs. It usually takes the form of elongated or filamentary structures, typically extending between 10 and 30 kpc, but also reaching distances of ∼80 kpc. We find that the large-scale ionized gas structures show a tendency to be oriented at large angles from the radio axis, and that the gas on a scale of a few kiloparsecs from the nucleus often shows ordered rotation with a kinematical axis forming a median angle of 65° with the radio axis. We also discuss the velocity field and ionization properties of the EELRs. The observed emission line structures appear to be associated with gaseous “superdisks” that formed after a gas-rich merger. The different properties of the EELR can be explained with a combination of the source evolutionary state and the orientation of the superdisk with respect to the radio axis. The general alignment between the superdisks and radio axis might be produced by stable and coherent accretion maintained over long timescales.
The fundamental plane in the hierarchical context
Authors: D’Onofrio M. , Chiosi C.
Published: March 2022

Context. The fundamental plane (FP) relation and the distribution of early-type galaxies (ETGs) in the FP projections cannot be easily explained in the hierarchical framework, where galaxies grow up by merging and as a result of star formation episodes.

Aims. We want to show here that both the FP and its projections arise naturally from the combination of the virial theorem (VT) and a new time-dependent relation, describing how luminosity and stellar velocity dispersion change during galaxy evolution. This relation has the form of the Faber-Jackson relation, but a different physical meaning: the new relation is L = L0′(t)σβ(t), where its coefficients L0′ and β are time-dependent and can vary considerably from object to object, at variance with those obtained from the fit of the L − σ plane.

Methods. By combining the VT and L = L0′(t)σβ(t) law, we derived an equation for each galaxy that is identical in form to the FP, but with coefficients depending on β. This allowed us to extract the solutions for β as a function of the structural parameters of ETGs and consequently calculate the coefficients of the FP-like equations.

Results. We demonstrate that the observed properties of ETGs in the FP and its projections can be understood in terms of variations of β and L0′. These two parameters encrypt the history of galaxy evolution across the cosmic epochs and determine the future aspect of the FP and its projections. In particular, we show that the FP coefficients are simple averages of those in the FP-like equations valid for each galaxy, and that the variations of β naturally explain the distributions of ETGs observed in the FP projections and the direction of the border of the Zone of Exclusion.
Detection of periodic flares in 6.7 GHz methanol masers G45.804−0.356 and G49.043−1.079
Authors: Olech M. , Durjasz M. , Szymczak M. , Bartkiewicz A.
Published: March 2022

Context. Periodicity in 6.7 GHz methanol maser sources is a rare phenomenon that was discovered during long-term monitoring programmes. Understanding the underlying processes that lead to periodic variability might provide insights into the physical processes in high-mass star-forming regions.

Aims. We aim to identify and describe new periodic methanol masers.

Methods. The observations were obtained with the Torun 32 m antenna. Time series analysis was conducted using well-proven statistical methods. Additionally, NEOWISE data were used to search for a correlation between infrared and maser fluxes.

Results. We found two new periodic sources, G45.804−0.356 and G49.043−1.079, with periods of 416.9 and 469.3 days, respectively. For G49.043−1.079, infrared variability is simultaneous with methanol flares.

Conclusions. A most likely cause of the periodicity in G49.043−1.079 is modulated accretion. For G45.804-0.356, the periodicity cannot be explained with the available data, and further research is needed.
Research on air material configuration technology of domestic civil aircraft under air material sharing
Authors: Feng Yunwen , Pan Weihuang , Liu Jiaqi , Lu Cheng , Xue Xiaofeng
Published: March 2022

In order to improve the comprehensive logistics support capability of domestic and foreign civil aircraft markets, and reduce the number of air materiel configuration and the cost of air materiel operation support, this paper proposes an air materiel configuration method based on air materiel sharing mode, considering the air materiel inventory and response time of each terminal. The Poisson process is used to describe the probabilities of different demand quantities of aviation materials during the study time; the aviation materials sharing group is constructed according to the transportation time relationship between the terminals; the marginal analysis method is used to expect largest number short-term aviation materials of all terminals in the sharing group to carry out air material configuration until the fleet availability needs are met, and the air material configuration technology under the sharing of air materials is realized. Studies have shown that under the specified fleet availability, the use of air material configuration technology under the condition of air material sharing can reduce the number of air materials in each terminal; the availability of the fleet can be improved under the same configuration number; The initial inventory can be maintained at a low level in the terminal group under the sharing condition. the research work has certain reference significance for improving the maintenance and support system of Chinese civil aircraft.
Virtual beam generation and guidance command calculation in FLS advanced approach process
Authors: Zhai Shaobo , Li Guangwen , Xue Guanglong , Jia Qiuling , Sun Xiaomin
Published: March 2022

FLS approach is an effective means to improve approach perception and reduce operational risk, and it is one of the key functions of flight management system of advanced commercial aircraft. This paper studies the generating virtual beam, calculating beam deviation and guidance command in FLS advanced approach guidance technology, and proposes a method of generating virtual beam based on navigation database information and a method of calculating beam deviation based on spatial geometric relationship. The guidance law was constructed based on angle deviation and lateral distance between the actual path and FLS beam, and the simulation test examle was designed to verity the deviation and guidance command calculation algorithm. The simulation results show that the FLS guidance algorithm proposed in this paper can achieve high-accuracy approach guidance.
Quantifying microstructural changes in chocolate under shear, heating
Authors: Piccone Ashley
Published: March 2022

Heating followed by cooling and shearing impacts the crystalline network structure of chocolate differently, significantly influencing the product quality.
Electron–neutral collisions effects on Langmuir probe in the lower E-region ionosphere
Authors: Brask S. M. , Marholm S. , Di Mare F. , Adhikari S. , Spicher A. , Takahashi T. , Miloch W. J.
Published: March 2022

We present the first set of particle-in-cell simulations including Monte Carlo collisions between charged and neutral particles used to simulate a cylindrical Langmuir probe in the electron saturation regime with a collisional electron sheath. We use a setup focused on the E-region ionosphere; however, the results of these simulations are analyzed in a general sense using dimensionless values. We find that the electron currents get enhanced as the collision frequency for electrons increases and the values of λe/λD→1, where λe is the electron mean free path and λD is the electron Debye length. In addition, we apply the simulation results to a sounding rocket experiment and show how we can correct the currents for the Investigation of Cusp Irregularities-4 sounding rocket due to collisions while it flies through the E-region.
VO2-metallic hybrid metasurfaces for agile terahertz wave modulation by phase transition
Authors: Zhu Hongfu , Li Jiang , Du Lianghui , Shan Lijun , Li Peng , Lu Xueguang , Feng Tangdong , Das Sujit , Huang Wanxia , Shi Qiwu , Zhu Liguo
Published: March 2022

The combination of VO2 and metasurfaces has opened an attractive route to dynamically control terahertz (THz) waves based on the giant conductivity change. However, the high-precision control of microfabrication and single performance of conductivity change limit the multifunctional application of VO2-based metasurfaces. Here, we proposed a VO2-metallic hybrid metasurface by in situ depositing high-quality VO2 thin films onto a metasurface composed of asymmetric Fano resonance units. It exhibits agile frequency and amplitude modulation for THz transmission across tuning the dielectric constant and conductivity of VO2. The metallic metasurface is designed as a matrix to achieve high transmission at 0.61 and 0.78 THz due to the split-ring resonance. During the thermally triggered phase transition of VO2, we found that the resonance frequency and amplitude can be tuned dominantly by the change of dielectric constant and conductivity, respectively. In particular, the increased dielectric constant enables red shift of the frequency by around 0.48 THz and the conductivity increases lead to a giant THz amplitude modulation of 88%. These results provide a route for developing VO2-based THz smart devices combined with functional metasurfaces and hold great promise for applications in THz sensor and modulation.
Broadband acoustic insulation via gradient impedance boundary waveguide
Authors: Liu Ming-Hao , Li Xin , Zou Xin-Ye , Cheng Jian-Chun
Published: March 2022

In this work, we analytically and experimentally present a perfect and broadband acoustic insulation waveguide composed of gradient impedance boundaries. With these designed impedance boundaries, the incident plane wave will be converted into the surface wave mode and be absorbed or reflected back. The transmission rate reaches nearly zero in a broadband (1800–7000 Hz, typically), and the bandwidth is adjustable to fit different noise spectra. Our results may contribute more possible designs for noise reduction challenges in the waveguide.
On the similarities between the simplified Phan-Thien–Tanner model and the finitely extensible nonlinear elastic dumbbell (Peterlin closure) model in simple and complex flows
Authors: Davoodi M. , Zografos K. , Oliveira P. J. , Poole R. J.
Published: March 2022

For many commonly used viscoelastic constitutive equations, it is well known that the limiting behavior is that of the Oldroyd-B model. Here, we compare the response of the simplified linear form of the Phan-Thien–Tanner model (“sPTT”) [Phan-Thien and Tanner, “A new constitutive equation derived from network theory,” J. Non-Newtonian Fluid Mech. 2, 353–365 (1977)] and the finitely extensible nonlinear elastic (“FENE”) dumbbell model that follows the Peterlin approximation (“FENE-P”) [Bird et al., “Polymer solution rheology based on a finitely extensible bead—Spring chain model,” J. Non-Newtonian Fluid Mech. 7, 213–235 (1980)]. We show that for steady homogeneous flows such as steady simple shear flow or pure extension, the response of both models is identical under precise conditions (ε=1/L2). The similarity of the “spring” functions between the two models is shown to help understand this equivalence despite a different molecular origin of the two models. We then use a numerical approach to investigate the response of the two models when the flow is “complex” in a number of different definitions: first, when the applied deformation field is homogeneous in space but transient in time (so-called “start-up” shear and planar extensional flow), then, as an intermediate step, the start-up of the planar channel flow; and finally, “complex” flows (through a range of geometries), which, although being Eulerian steady, are unsteady in a Lagrangian sense. Although there can be significant differences in transient conditions, especially if the extensibility parameter is small L2>100,ε<0.01, under the limit that the flows remain Eulerian steady, we once again observe very close agreement between the FENE-P dumbbell and sPTT models in complex geometries.
Spin-state-controlled chemi-ionization reactions between metastable helium atoms and ground-state lithium atoms
Authors: Sixt Tobias , Stienkemeier Frank , Dulitz Katrin
Published: March 2022

We demonstrate the control of 4He(23S1)–7Li(22S1/2) chemi-ionization reactions by all-optical electron-spin-state preparation of both atomic species prior to the collision process. Our results demonstrate that chemi-ionization is strongly suppressed (enhanced) for non-spin-conserving (spin-conserving) collisions at thermal energies. These findings are in good agreement with a model based on spin angular momentum coupling of the prepared atomic states to the quasi-molecular states. Small deviations from the model indicate the contribution of the 4Σ+ channel to the reaction rate, which is in violation of spin conservation.
Self-diffusiophoresis of Janus particles that release ions
Authors: Asmolov Evgeny S. , Nizkaya Tatiana V. , Vinogradova Olga I.
Published: March 2022

Catalytic Janus swimmers demonstrate a diffusiophoretic motion by self-generating the gradients of concentrations and electric potential. Recent work has focused on simplified cases, such as a release of solely one type of ions or low surface fluxes of ions, with limited theoretical guidance. Here, we consider the experimentally relevant case of particles that release both types of ions, and obtain a simple expression for a particle velocity in the limit of the thin electrostatic diffuse layer. Our approximate expression is very accurate even when ion fluxes and surface potentials are large and allows one to interpret a number of intriguing phenomena, such as the reverse in the direction of the particle motion in response to variations of the salt concentration or self-diffusiophoresis of uncharged particles.
Satellite magnetic data reveal interannual waves in Earth’s core
Authors: Gillet Nicolas , Gerick Felix , Jault Dominique , Schwaiger Tobias , Aubert Julien , Istas Mathieu
Published: March 2022

Significance

The physics responsible for most of the interannual geomagnetic field changes, continually recorded by satellites for 20 years, is a long-standing open issue. By analyzing magnetic data, we detect Magneto–Coriolis waves in the Earth’s outer core that account for a significant part of this signal. We further propose theoretical advances in the physical characterization of these waves, enabling a deeper understanding of the dynamics behind the geomagnetic signal. It should allow one to better sketch the heterogeneous magnetic field deep within the core, shedding further light on the mechanisms that sustain the geodynamo. Our interpretation does not require the presence of a stratified layer at the top of the core, with potent consequences regarding the Earth’s thermal history.
Photopharmacological modulation of native CRAC channels using azoboronate photoswitches
Authors: Udasin Ronald , Sil Anwesha , Zomot Elia , Achildiev Cohen Hadas , Haj Jozafina , Engelmayer Nurit , Lev Shaya , Binshtok Alexander M. , Shaked Yuval , Kienzler Michael A. , Palty Raz
Published: March 2022

Significance

Calcium release–activated calcium (CRAC) channels play key roles in the regulation of cellular signaling, transcription, and migration. Here, we describe the design, chemical synthesis, and characterization of photoswitchable channel inhibitors that can be switched on and off depending on the wavelength of light used. We use the compounds to induce light-dependent modulation of channel activity and downstream gene expression in human immune cells. We further expand the usage of the compounds to control seeding of cancer cells in target tissue and regulation of response to noxious stimuli in vivo in mice.
The age of the opening of the Ice-Free Corridor and implications for the peopling of the Americas
Authors: Clark Jorie , Carlson Anders E. , Reyes Alberto V. , Carlson Elizabeth C. B. , Guillaume Louise , Milne Glenn A. , Tarasov Lev , Caffee Marc , Wilcken Klaus , Rood Dylan H.
Published: March 2022

Significance

The Ice-Free Corridor (IFC) has long played a key role in hypotheses about the peopling of the Americas. Earlier assessments of its age suggested that the IFC was available for a Clovis-first migration, but subsequent developments now suggest a pre-Clovis occupation of the Americas that occurred before the opening of the IFC, thus supporting a Pacific coastal migration route instead. However, large uncertainties in existing ages from the IFC cannot preclude its availability as a route for the first migrations. Resolving this debate over migration route is important for addressing the questions of when and how the first Americans arrived. We report cosmogenic nuclide exposure ages that show that the final opening of the IFC occurred well after pre-Clovis occupation.
sEH-derived metabolites of linoleic acid drive pathologic inflammation while impairing key innate immune cell function in burn injury
Authors: Bergmann Christian B. , McReynolds Cindy B. , Wan Debin , Singh Nalin , Goetzman Holly , Caldwell Charles C. , Supp Dorothy M. , Hammock Bruce D.
Published: March 2022

Significance

Oxylipins alter immune cell function and potentially drive pathophysiology in burn and sepsis patients. Past and recent data reveal a correlation between increased systemic EpOME levels and reduced survival in human burn trauma and sepsis. This work extends these studies and provides evidence that the downstream sEH-derived metabolites, DiHOMEs, are driving worsening outcomes by altering the immune response. Inhibiting DiHOME metabolite formation with the sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), restored immune function by increasing immune cell survival and function. These data support the hypothesis that sEH-derived linoleic acid diols are responsible for increased mortality in burn and sepsis patients and also provide a rationale for testing the therapeutic blockage of DiHOME generation in burn and sepsis patients to improve their outcomes.
A sociopragmatic account of religiosity and secularity in fictional narratives
Authors: Elsaadany Kamel Abdelbadie
Published: March 2022

This paper investigates the religiosity/secularity dichotomy in Naguib Mahfouz’s novels, which is shaped by cultural narratives that convey his ideas. It analyzes a defined corpus of Mahfouz’s narratives that articulate his notions of religiosity/secularity. Through an interdisciplinary methodology combining the application of pragmatics, interactional sociolinguistics, and contextual analysis, it aims to determine Mahfouz’s potentiality for perceiving and narrativizing religiosity and secularity in twentieth-century Egypt. It discusses how Mahfouz adopts sociopragmatic techniques to give a bright picture of the secularist discourse but a negative one for the Islamist one presented as inevitably incapable, crude, schizophrenic and idiosyncratic. Mahfouz openly destabilizes the religious/secular dichotomy by juxtaposing religious and secular discourses in his early and later narratives, where he scrutinizes secularity, advocating it as the only way out of and uprooting, religiosity. The adoption of an interdisciplinary framework proves to be theoretically and empirically motivated in order to show how Mahfouz’s narratives reflect their originator’s own beliefs and those of the narrated society, including its value systems.
A mathematical model to quantify RYR Ca2+ leak and associated heat production in resting human skeletal muscle fibers
Authors: Barclay Christopher J. , Launikonis Bradley S.
Published: March 2022

Cycling of Ca2+ between the sarcoplasmic reticulum (SR) and myoplasm is an important component of skeletal muscle resting metabolism. As part of this cycle, Ca2+ leaks from the SR into the myoplasm and is pumped back into the SR using ATP, which leads to the consumption of O2 and generation of heat. Ca2+ may leak through release channels or ryanodine receptors (RYRs). RYR Ca2+ leak can be monitored in a skinned fiber preparation in which leaked Ca2+ is pumped into the t-system and measured with a fluorescent dye. However, accurate quantification faces a number of hurdles. To overcome them, we developed a mathematical model of Ca2+ movement in these preparations. The model incorporated Ca2+ pumps that move Ca2+ from the myoplasm to the SR and from the junctional space (JS) to the t-system, Ca2+ buffering by EGTA in the JS and myoplasm and by buffers in the SR, and Ca2+ leaks from the SR into the JS and myoplasm and from the t-system into the myoplasm. The model accurately simulated Ca2+ uptake into the t-system, the relationship between myoplasmic [Ca2+] and steady-state t-system [Ca2+], and the effect of blocking RYR Ca2+ leak on t-system Ca2+ uptake. The magnitude of the leak through the RYRs would contribute ∼5% of the resting heat production of human muscle. In normal resting fibers, RYR Ca2+ leak makes a small contribution to resting metabolism. RYR-focused pathologies have the potential to increase RYR Ca2+ leak and the RYR leak component of resting metabolism.
Improved stabilization scheme for extreme ultraviolet quantum interference experiments
Authors: Uhl Daniel , Wituschek Andreas , Bangert Ulrich , Binz Marcel , Callegari Carlo , Di Fraia Michele , Plekan Oksana , Prince Kevin Charles , Cerullo Giulio , Giannessi Luca , Danailov Miltcho , Sansone Giuseppe , Laarmann Tim , Michiels Rupert , Mudrich Marcel , Piseri Paolo , Squibb Richard James , Feifel Raimund , Stranges Stefano , Stienkemeier Frank , Bruder Lukas
Published: March 2022

Interferometric pump–probe experiments in the extreme ultraviolet (XUV) domain are experimentally very challenging due to the high phase stability required between the XUV pulses. Recently, an efficient phase stabilization scheme was introduced for seeded XUV free electron lasers (FELs) combining shot-to-shot phase modulation with lock-in detection Wituschek et al (2020 Nat. Commun.
11 883). This method stabilized the seed laser beampath on the fundamental ultraviolet wavelength to a high degree. Here, we extend this scheme including the stabilization of the XUV beampath, incorporating phase fluctuations from the FEL high gain harmonic generation process. Our analysis reveals a clear signal improvement with the new method compared to the previous stabilization scheme.
Exploring temperature dependent electron–electron interaction of rocksalt SnS and SnSe within Matsubara-time domain
Authors: Sihi Antik , Pandey Sudhir K
Published: March 2022

Both experimental and theoretical studies show non-trivial topological behaviour in native rocksalt phase for SnS and SnSe and categorize these materials in topological crystalline insulators. Here, the detailed electronic structures studies of SnS and SnSe in the rocksalt phase are carried out using many-body GW based theory and density functional theory both for ground states and temperature dependent excited states. The estimated values of fundamental direct bandgaps around L-point using G
0
W
0 (mBJ) are ∼0.27 (∼0.13) eV and ∼0.37 (∼0.17) eV for SnS and SnSe, respectively. The strength of hybridization between Sn 5p and S 3p (Se 4p) orbitals for SnS (SnSe) shows strong k-dependence. The behaviour of

W

¯

(ω), which is the averaged value of diagonal matrix elements of fully screened Coulomb interaction, suggests to use full-GW method for exploring the excited states because the correlation effects within these two materials are relatively weak. The temperature dependent electronic structure calculations for SnS and SnSe provide linearly decreasing behaviour of bandgaps with rise in temperatures. The existence of collective excitation of quasiparticles in form of plasmon is predicted for these compounds, where the estimated values of plasmon frequency are ∼9.5 eV and ∼9.3 eV for SnS and SnSe, respectively. The imaginary part of self-energy and mass renormalization factor (Z

k
(ω)) due to electron–electron interaction (EEI) are also calculated along W–L–Γ direction for both the materials, where the estimated ranges of Z

k
(ω) are 0.70 to 0.79 and 0.71 to 0.78 for SnS and SnSe, respectively, along this k-direction. The present comparative study reveals that the behaviour of temperature dependent EEI for SnS and SnSe are the almost same and EEI is important for high temperature transport properties.
Reducing leakage current and enhancing polarization in multiferroic 3D super-nanocomposites by microstructure engineering
Authors: Enriquez Erik , Lu Ping , Li Leigang , Zhang Bruce , Wang Haiyan , Jia Quanxi , Chen Aiping
Published: March 2022

Multiferroic materials have generated great interest due to their potential as functional device materials. Nanocomposites have been increasingly used to design and generate new functionalities by pairing dissimilar ferroic materials, though the combination often introduces new complexity and challenges unforeseeable in single-phase counterparts. The recently developed approaches to fabricate 3D super-nanocomposites (3D‐sNC) open new avenues to control and enhance functional properties. In this work, we develop a new 3D‐sNC with CoFe2O4 (CFO) short nanopillar arrays embedded in BaTiO3 (BTO) film matrix via microstructure engineering by alternatively depositing BTO:CFO vertically-aligned nanocomposite layers and single-phase BTO layers. This microstructure engineering method allows encapsulating the relative conducting CFO phase by the insulating BTO phase, which suppress the leakage current and enhance the polarization. Our results demonstrate that microstructure engineering in 3D‐sNC offers a new bottom–up method of fabricating advanced nanostructures with a wide range of possible configurations for applications where the functional properties need to be systematically modified.
Fe3O4-doped silk fibroin-polyacrylamide hydrogel for selective and highly efficient absorption of cationic dyes pollution in water
Authors: Hu Yongqin , Hou Chen , An Jia , Fang Junan , Shi Yuxia , Fan Qianxi , Liu Guoyi , Liu Yufei
Published: March 2022

Overuse of organic dyes has caused serious threats to the ecosystem and human health. However, the development of high-efficient, environmentally friendly, selective, and degradable cationic dye adsorbents remains a huge challenge. In this work, a novel Fe3O4 nanoparticles doped silk fibroin-polyacrylamide magnetic hybrid hydrogel (Fe3O4@SF-PAAM) was successfully fabricated by combining free radical polymerization to prepare hydrogels and in situ co-precipitation to prepare nanoparticles. The obtained Fe3O4@SF-PAAM hydrogel shows strong magnetic performance with saturated magnetic of 10.2 emu mg−1 and excellent swelling properties with a swelling ratio of 55867%. In addition, Fe3O4@SF-PAAM can adsorb cationic dyes such as methylene blue (MB), crystal violet, and Rhodamine B, but has no adsorption effect on anionic dyes such as methyl orange, congo red, and carmine, indicating that Fe3O4@SF-PAAM has good selective adsorption properties for cationic dyes. Interestingly, the adsorption capacity of Fe3O4@SF-PAAM was approached 2025 mg g–1 for MB (MB, a typical cation dye) at 25 °C and neutral. Meanwhile, the hybrid hydrogel is reusable, the removal rate for MB is still over 90% after the five adsorption–desorption cycles. The fabricated magnetic hybrid hydrogel is a kind of a highly-efficiency and eco-friendly adsorbent and presents great potential applications in water purification and environmental protection.
Individual pulse monitoring and dose control system for pre-clinical implementation of FLASH-RT
Authors: Ashraf M Ramish , Rahman Mahbubur , Cao Xu , Duval Kayla , Williams Benjamin B , Jack Hoopes P , Gladstone David J , Pogue Brian W , Zhang Rongxiao , Bruza Petr
Published: March 2022

Objective. Existing ultra-high dose rate (UHDR) electron sources lack dose rate independent dosimeters and a calibrated dose control system for accurate delivery. In this study, we aim to develop a custom single-pulse dose monitoring and a real-time dose-based control system for a FLASH enabled clinical linear accelerator (Linac). Approach. A commercially available point scintillator detector was coupled to a gated integrating amplifier and a real-time controller for dose monitoring and feedback control loop. The controller was programmed to integrate dose for each radiation pulse and stop the radiation beam when the prescribed dose was delivered. Additionally, the scintillator was mounted in a solid water phantom and placed underneath mice skin for in vivo dose monitoring. The scintillator was characterized in terms of its radiation stability, mean dose-rate (

D
̇

m

), and dose per pulse (D
p) dependence. Main results. The D
p exhibited a consistent ramp-up period across ∼4–5 pulse. The plastic scintillator was shown to be linear with

D
̇

m

(40–380 Gy s−1) and D
p (0.3–1.3 Gy Pulse−1) to within +/− 3%. However, the plastic scintillator was subject to significant radiation damage (16%/kGy) for the initial 1 kGy and would need to be calibrated frequently. Pulse-counting control was accurately implemented with one-to-one correspondence between the intended and the actual delivered pulses. The dose-based control was sufficient to gate on any pulse of the Linac. In vivo dosimetry monitoring with a 1 cm circular cut-out revealed that during the ramp-up period, the average D
p was ∼0.045 ± 0.004 Gy Pulse−1, whereas after the ramp-up it stabilized at 0.65 ± 0.01 Gy Pulse−1. Significance. The tools presented in this study can be used to determine the beam parameter space pertinent to the FLASH effect. Additionally, this study is the first instance of real-time dose-based control for a modified Linac at ultra-high dose rates, which provides insight into the tool required for future clinical translation of FLASH-RT.
Painlevé analysis and higher-order rogue waves of a generalized (3+1)-dimensional shallow water wave equation
Authors: Singh Sudhir , Sakkaravarthi K , Tamizhmani T , Murugesan K
Published: March 2022

Considering the importance of ever-increasing interest in exploring localized waves, we investigate a generalized (3+1)-dimensional Hirota-Satsuma-Ito equation describing the unidirectional propagation of shallow-water waves and perform Painlevé analysis to understand its integrability nature. We construct the explicit form of higher-order rogue wave solutions by adopting Hirota’s bilinearization and generalized polynomial functions. Further, we explore their dynamics in detail, depicting different pattern formation that reveal potential advantages with available arbitrary constants in their manipulation mechanism. Particularly, we demonstrate the existence of singly-localized line-rogue waves and doubly-localized rogue waves with multiple (single, triple, and sextuple) structures generating triangular and pentagon type geometrical patterns with controllable orientations that can be altered appropriately by tuning the parameters. The presented analysis will be an essential inclusion in the context of rogue waves in higher-dimensional systems.
Primordial black hole dark matter in the presence of p-wave WIMP annihilation
Authors: Kadota Kenji , Tashiro Hiroyuki
Published: March 2022

We study the allowed primordial black hole (PBH) dark matter abundance in the mixed dark matter scenarios consisting of PBHs and self-annihilating weakly interacting massive particles (WIMPs) with a velocity dependent annihilation cross section. We first briefly illustrate how the WIMP dark matter halo profile changes for the velocity suppressed p-wave annihilation scenarios, compared with the familiar s-wave annihilation scenarios, and then discuss the PBH mass dependent upper bound on the allowed PBH dark matter abundance.

The WIMPs can accrete onto a PBH to form an ultracompact minihalo with a spiky density profile. Such a spike is moderated in the central region of a halo because the WIMPs are annihilated away and this moderation is less effective for a smaller annihilation cross section. The WIMP core density becomes larger while the core radius becomes smaller for a velocity suppressed p-wave annihilation cross section than those for the s-wave annihilation scenarios.
The annihilation cross section is dependent on the velocity which varies across the halo, and, in addition to the change of the WIMP density profile, another interesting feature is the PBH mass dependent bound on PBH dark matter abundance. This is in stark contrast to the s-wave annihilation scenarios where the PBH abundance bound is independent of the PBH mass. The allowed PBH dark matter fraction (with respect to the total dark matter abundance) is of order f
PBH ≲ 𝒪(10−7)(M⊙/MPBH)(−6+2γsp)/(3γsp+3) for the thermal relic p-wave dark matter with the mass 100 GeV where γsp is the slope index of the spike profile, to be compared with f
PBH ≲ 𝒪(10−9) for the corresponding thermal relic s-wave dark matter scenarios.
Influence of triangularity on the plasma response to resonant magnetic perturbations
Authors: Gu S. , Paz-Soldan C. , Liu Y.Q. , Sun Y. , Lyons B.C. , Ryan D.A. , Weisberg D. , Leuthold N. , Willensdorfer M. , Suttrop W. , Park J.-K. , Logan N.C. , Shafer M.W. , Wang H.H. , Ma Q. , Kirk A. , Tal B. , Griener M.
Published: March 2022

The effect of the axisymmetric plasma shape on the non-axisymmetric plasma response to resonant magnetic perturbations is investigated in experiment and modeling for the DIII-D, EAST and ASDEX Upgrade tokamaks. Systematically modeling the effect of the triangularity, whilst keeping other equilibrium quantities largely unchanged, reveals that the plasma response is strongly suppressed at high triangularity compared to that at low triangularity. This is validated through targeted comparison with experiments at DIII-D, EAST, and ASDEX Upgrade. DIII-D and EAST magnetic measurements are used to validate simulations, while at ASDEX Upgrade the plasma edge displacement is measured. Both experiments and modeling find a reduced magnetic plasma response on the high-field side at high triangularity across devices. Multi-modal analysis of the simulation results extracts the mode structure and applied spectrum dependence of each mode. The amplitude of the dominant mode reveals similar trends with the edge resonance and radial displacement near the X-point, which suggests that the multi-mode plasma response provides another way to understand the edge localized mode (ELM) control physics. The plasma response is strongly reduced at high triangularity compared to that at low triangularity, which implies different ELM control effects as shaping is varied. These findings indicate that the plasma shape should be taken into consideration when designing an RMP-ELM control strategy in experiment, and that predictive plasma response calculations can be used to maximize access to RMP-ELM control in future devices by maximizing the coupling between coils and the plasma.
Finite magnetic well effects on resistive and drift-resistive ballooning modes in a shaped tokamak
Authors: Brunetti D. , Ham C.J. , Saarelma S. , Graves J.P. , Connor J.W. , Kleiner A.
Published: March 2022

The impact of plasma shaping through magnetic well modifications on the stability of resistive ballooning modes (RBMs) in tokamaks is analysed, also including finite diamagnetic flows. Various limiting cases of the dispersion relation, obtained by matching the ballooning equation across the ideal and resistive layers, are analysed. It is found that stability is generally improved by the combination of vertical elongation and positive triangularity, although, in some cases, the growth rate of the unstable mode can be enhanced by these effects. Usually, vertically elongated plasmas with no triangularity are prone to exhibit worse stability properties. A value for the critical β above which RBMs are driven unstable is identified, and a connection with type-III ELM activity is established.
Line crossing’s effect on the hatching performance of Japanese quail
Authors: Mirnita D A I , Dewanti R , Cahyadi M , Wati A K
Published: March 2022

Seedlings are one of the factors affecting egg production in quails and the possible efforts to obtain superior seeds include crossing. Therefore, this study was conducted to observe the hatching performance of Japanese quails subjected to line crossing. The materials used were hatching eggs produced by a crossbreeding between the brown male and black female species. Twenty brown male and eighty black female quails were used to produce hatching eggs with a male-to-female ratio of 1: 4. Up to 242 and 239 hatching eggs obtained from Cross 1 and 2 respectively were used. The t-test analysis results were not significantly different (P>0.05), where egg weight = 0.155 and hatching weight = 0.6405. However, the egg index of 0.02617 and the hatching length of 0.02589 were significantly different (P<0.05). At Cross 1, the low hatching mortality was 9.2%, and the high hatching quality was 83.88%. Generally, it was discovered that the products in Cross 1 and 2 have the same performance in terms of hatching weight, mortality, and quality, as well as the egg weight but the line crossing affected the egg index and hatching time. These results are expected to assist the development of a quail breeding strategy in the future.
Frequency control strategies in a renewable energy intensive power system: options for South Africa
Authors: Mzamo Ntombizodwa V. , Manditereza Patrick T.
Published: March 2022

Inertia reduction due to high-level penetration of converter interfaced components may result in frequency stability issues. The paper analyses different frequency strategies for both solar photovoltaic (PV) and wind generators to support inertia, and also evaluates the contribution of synchronous condensers (SCs) to the system inertia of the power grid. Decommissioned power plants can potentially be retrofitted to SC mode in order to provide inertia support after they are retired. This paper investigates the various frequency control strategies available to the South Africa power grid in the face of increasing renewable energy integration, and makes a case for the modification of the many mothballed coal-fired power plants to SC mode.
Engineering an effective three-spin Hamiltonian in trapped-ion systems for applications in quantum simulation
Authors: Andrade Bárbara , Davoudi Zohreh , Graß Tobias , Hafezi Mohammad , Pagano Guido , Seif Alireza
Published: March 2022

Trapped-ion quantum simulators, in analog and digital modes, are considered a primary candidate to achieve quantum advantage in quantum simulation and quantum computation. The underlying controlled ion–laser interactions induce all-to-all two-spin interactions via the collective modes of motion through Cirac–Zoller or Mølmer–Sørensen schemes, leading to effective two-spin Hamiltonians, as well as two-qubit entangling gates. In this work, the Mølmer–Sørensen scheme is extended to induce three-spin interactions via tailored first- and second-order spin–motion couplings. The scheme enables engineering single-, two-, and three-spin interactions, and can be tuned via an enhanced protocol to simulate purely three-spin dynamics. Analytical results for the effective evolution are presented, along with detailed numerical simulations of the full dynamics to support the accuracy and feasibility of the proposed scheme for near-term applications. With a focus on quantum simulation, the advantage of a direct analog implementation of three-spin dynamics is demonstrated via the example of matter-gauge interactions in the U(1) lattice gauge theory within the quantum link model. The mapping of degrees of freedom and strategies for scaling the three-spin scheme to larger systems, are detailed, along with a discussion of the expected outcome of the simulation of the quantum link model given realistic fidelities in the upcoming experiments. The applications of the three-spin scheme go beyond the lattice gauge theory example studied here and include studies of static and dynamical phase diagrams of strongly interacting condensed-matter systems modeled by two- and three-spin Hamiltonians.