bluuebunny/crossref_metadata_2025_split huggingface dataset:
Global convergence rates from relaxed Euler equations to Navier–Stokes equations with Oldroyd-type constitutive laws
Authors: Peng Yue-Jun , Zhao Liang 
Published: August 2024

Abstract
In a previous work (Peng and Zhao 2022 J. Math. Fluid Mech.
24 29), it is proved that the 1D full compressible Navier–Stokes equations for a Newtonian fluid can be approximated globally-in-time by a relaxed Euler-type system with Oldroyd’s derivatives and a revised Cattaneo’s constitutive law. These two relaxations turn the whole system into a first-order quasilinear hyperbolic one with partial dissipation. In this paper, we establish the global convergence rates between the smooth solutions to the relaxed Euler-type system and the Navier–Stokes equations over periodic domains. For this purpose, we use stream function techniques together with energy estimates for error systems. These techniques may be applicable to more complicated systems.
Dosimetry for repetitive transcranial magnetic stimulation: a translational study from Alzheimer’s disease patients to controlled in vitro investigations
Authors: Camera Francesca , Colantoni Eleonora , Casciati Arianna , Tanno Barbara , Mencarelli Lucia , Di Lorenzo Francesco , Bonnì Sonia , Koch Giacomo , Merla Caterina 
Published: August 2024

Abstract

Objective. Recent studies have indicated that repetitive transcranial magnetic stimulation (rTMS) could enhance cognition in Alzheimer’s Disease (AD) patients, but to now the molecular-level interaction mechanisms driving this effect remain poorly understood. While cognitive scores have been the primary measure of rTMS effectiveness, employing molecular-based approaches could offer more precise treatment predictions and prognoses. To reach this goal, it is fundamental to assess the electric field (E-field) and the induced current densities (J) within the stimulated brain areas and to translate these values to in vitro systems specifically devoted in investigating molecular-based interactions of this stimulation. Approach. This paper offers a methodological procedure to guide dosimetric assessment to translate the E-field induced in humans (in a specific pilot study) into in vitro settings. Electromagnetic simulations on patients’ head models and cellular holders were conducted to characterize exposure conditions and determine necessary adjustments for in vitro replication of the same dose delivered in humans using the same stimulating coil. Main results. Our study highlighted the levels of E-field and J induced in the target brain region and showed that the computed E-field and J were different among patients that underwent the treatment, so to replicate the exposure to the in vitro system, we have to consider a range of electric quantities as reference. To match the E-field to the levels calculated in patients’ brains, an increase of at least the 25% in the coil feeding current is necessary when in vitro stimulations are performed. Conversely, to equalize current densities, modifications in the cells culture medium conductivity have to be implemented reducing it to one fifth of its value. Significance. This dosimetric assessment and subsequent experimental adjustments are essential to achieve controlled in vitro experiments to better understand rTMS effects on AD cognition. Dosimetry is a fundamental step for comparing the cognitive effects with those obtained by stimulating a cellular model at an equal dose rigorously evaluated.
A terahertz broadband and narrowband switchable absorber based on joint modulation of vanadium dioxide and graphene surfaces
Authors: Zhang Ying , Zhou Xingtong , Li You 
Published: August 2024

Abstract
In this paper, a terahertz broadband and narrowband switchable absorber is proposed. The absorption performance tuning for both broadband and narrowband functions is realized based on the joint modulation of vanadium dioxide (VO2) and graphene surfaces. Concretely, while VO2 is in the metallic state, the absorber achieves broadband absorption function. The overall bandwidth of over 90% absorption is 4.04 THz corresponding to a relative bandwidth of 84%. Through regulating the conductivity of VO2, dynamic tuning of the absorption amplitude is obtained and the modulation depth is 96%. By manipulating the graphene Femi energy and VO2 conductivity simultaneously, dynamic tuning of the absorption bandwidth is realized. In particular, the spectral center frequency of broadband absorption remains stable without drifting during the tuning process. While VO2 is in the insulating state, the absorber achieves narrowband absorption function. Calculated results show that two separate perfect absorption peaks are formed, and the absorption amplitudes are 99.6% and 99.2% respectively. Through regulating the Fermi energy of graphene surface, the dynamic tuning of narrowband absorption frequency is realized. Compared with the ones reported in recent years, our absorber has the advantage on function realization, absorption characteristics and performance tuning.
ITER materials irradiation within the D–T neutron environment at JET: post-irradiation radioactivity analysis following the DTE2 experimental campaign
Authors: Packer L.W. , Batistoni P. , Bearcroft C. , Bradnam S.C. , Eardley E. , Fabbri M. , Fonnesu N. , Gilbert M.R. , Ghani Z. , Gorzkiewicz K. , Grove C.L. , Kierepko R. , Łaszyńska E. , Lengar I. , Litaudon X. , Loreti S. , Mietelski J.W. , Pillon M. , Savva M.I. , Shand C.R. , Stamatelatos I.E. , Turner A.N. , Vasilopoulou T. , Villari R. , Wójcik-Gargula A. , Žohar A. ,   JET Contributors
Published: August 2024

Abstract
This work presents the results following the first irradiation of ITER materials samples in a tokamak D–T plasma environment operating at significant fusion power. The materials exposed to this nuclear environment at the Joint European Torus during the DTE2 experimental campaign that took place in 2021 include representative ITER samples from various components such as poloidal field coil jacket samples, toroidal field coil radial closure plate steels, EUROFER 97 steel, W and CuCrZr materials from the divertor, Inconel-718 and 316L stainless steel for blanket modules, as well as vacuum vessel forging samples. The experimental results discussed include high-resolution gamma spectrometry measurements and analysis conducted with the post-irradiated samples, of which there were 68 in total. These samples were exposed through different experimental campaigns, including deuterium, deuterium–tritium and tritium phases. Diagnostics that supported the analysis included 25 dosimetry foil-based neutron diagnostics and two ‘VERDI’ neutron spectrometry diagnostics. A further 12 samples for positron annihilation spectroscopy were also irradiated. The irradiation of all these samples took place in a long-term irradiation assembly located near the JET vacuum vessel. The post-irradiation analysis of the ITER material samples has yielded valuable insights into their material activation levels and radiation fields. Comparative assessments between experimental measurements and comprehensive neutronics simulations have demonstrated a significant level of agreement in this work, while also revealing some discrepancies in specific material instances. The data and interpretation from this work not only serve as a robust experimental foundation for enhancing the precision and predictability of neutronics simulation approaches for ITER and next-step devices but also present some opportunities for the refinement of simulation methodologies. In light of these findings, a series of recommendations have been proposed, aimed at improving confidence in nuclear predictions associated with materials that have been exposed to fusion nuclear environments and advancing understanding in this important domain.
Synchronous spring precipitation in Southeastern China and Bengal: a potential indicator for the Indian summer monsoon?
Authors: Fang Keyan , Zhou Feifei , Wu Hao , Tang Hui , Mei Zepeng , Li Jinbao , Ou Tinghai , Zhao Zheng , Chen Deliang 
Published: August 2024

Abstract
Spring precipitation in southeastern China and Bengal, occurring during the transitional phase from winter to summer monsoons, serves as a critical window into the dynamics of large-scale circulations and the subsequent summer monsoon. While many studies have analyzed spring precipitation in southeastern China and Bengal, their interconnections and implications for the summer monsoon have remained relatively under explored. We utilized the Empirical Orthogonal Function of spring precipitation to reveal Synchronous Spring Precipitation (SSP) in southeastern China and Bengal. This synchronicity is bridged by the East Asian Subtropical Jet (EASJ) that extends from Bengal to southeastern China. The EASJ was predominantly correlated with precipitation in southeastern China prior to the 1990s, while it developed a more profound connection with precipitation in Bengal after the 1990s. Notably, SSP anomalies occurred during the developing phase of the El Niño-Southern Oscillation (ENSO). The predictive capacity of SSP for the Indian summer monsoon (ISM) amplifies during periods of the intensified SSP-ENSO correlations and positive phase of the North Pacific Meridional Mode. Tree-ring based reconstructions spanning the past two centuries further corroborate the persistent linkages among the SSP, ISM, and ENSO. Our research sheds light on the intricate interplay of these factors and their significance in understanding and predicting the monsoon dynamics in the region.
Balancing livestock production and environmental outcomes in northern Australia’s tropical savanna under global change
Authors: Runting Rebecca K , King Darran , Nolan Martin , Navarro Javier , Marcos-Martinez Raymundo , Rhodes Jonathan R , Gao Lei , Watson Ian , Ash Andrew , Reside April E , Álvarez-Romero Jorge G , Wells Jessie A , Ritchie Euan G , Hadjikakou Michalis , Driscoll Don A , Connor Jeffery D , Garber Jonathan , Bryan Brett A 
Published: August 2024

Abstract
Livestock production is an integral part of the global food system and the livelihoods of local people, but it also raises questions of environmental sustainability due to issues such as greenhouse gas (GHG) emissions, biodiversity decline, land degradation, and water use. Further challenges to extensive livestock systems may arise from changes in climate and the global economy (particularly variation in prices for livestock and carbon). However, significant potential exists for both mitigating these impacts and adapting to change via altering stocking rates, managing fire, and supplementing cattle diets to reduce methane emissions. We developed an integrated, spatio-temporal modelling approach to assess the effectiveness of these options for land management in northern Australia’s tropical savanna under different global change scenarios. Performance was measured against a range of sustainability indicators, including environmental (GHG emissions, biodiversity, water intake, and land condition) and agricultural (profit, beef production) outcomes. Our model shows that maintaining historical stocking rates is not environmentally sustainable due to the accelerated land degradation exacerbated by a changing climate. However, planned early dry season burning substantially reduced emissions, and in our simulations was profitable under all global change scenarios that included a carbon price. Overall, the balance between production and environmental outcomes could be improved by stocking below modelled carrying capacity and implementing fire management. This management scenario was the most profitable (more than double the profit from maintaining historical stocking rates), prevented land degradation, and reduced GHG emissions by 23%. By integrating the cumulative impacts of climate change, external economic drivers, and management actions across a range of sustainability indicators, we show that the future of rangelands in Australia’s savannas has the potential to balance livestock production and environmental outcomes.
N-bein formalism for the parameter space of quantum geometry
Authors: Romero Jorge , Velasquez Carlos A , Vergara J David 
Published: August 2024

Abstract
This work introduces a geometrical object that generalizes the quantum geometric tensor; we call it N-bein. Analogous to the vielbein (orthonormal frame) used in the Cartan formalism, the N-bein behaves like a ‘square root’ of the quantum geometric tensor. Using it, we present a quantum geometric tensor of two states that measures the possibility of moving from one state to another after two consecutive parameter variations. This new tensor determines the commutativity of such variations through its anti-symmetric part. In addition, we define a connection different from the Berry connection, and combining it with the N-bein allows us to introduce a notion of torsion and curvature à la Cartan that satisfies the Bianchi identities. Moreover, the torsion coincides with the anti-symmetric part of the two-state quantum geometric tensor previously mentioned, and thus, it is related to the commutativity of the parameter variations. We also describe our formalism using differential forms and discuss the possible physical interpretations of the new geometrical objects. Furthermore, we define different gauge invariants constructed from the geometrical quantities introduced in this work, resulting in new physical observables. Finally, we present two examples to illustrate these concepts: a harmonic oscillator and a generalized oscillator, both immersed in an electric field. We found that the new tensors quantify correlations between quantum states that were unavailable by other methods.
Sensing electrical environments: mechanical object reconstruction via electrosensors
Authors: A Palmer Ryan , V Chenchiah Isaac , Robert Daniel 
Published: August 2024

Abstract
Increasing empirical evidence suggests that many terrestrial arthropods, such as bees, spiders, and caterpillars, sense electric fields in their environments. This relatively newly discovered sense may play a unique role within their broader sensory ecology, alongside other fundamental senses such as vision, hearing, olfaction, and aero-acoustic sensing. Deflectable hairs are the primary candidate for the reception of electrical stimuli. From the deflections of individually innervated hairs, the arthropod can transduce environmental and ecological information. However, it is unclear what information an animal can elicit from hair receptors and how it relates to their environment. This paper explores how an arthropod may ascertain geometric and electrical information about its environment. Using two-dimensional models, we explore the possibility of electroreceptive object recognition and reconstruction via multiple observations and several deflecting hairs. We analyse how the number of hairs, the observed shape, and the observation path alter the accuracy of the reconstructed representations. The results herein indicate the formidable possibility that geometric information about the environment can be electro-mechanically measured and acquired at a distance.
An approach to generate cross-polarization modulation-enabled optical frequency comb with enhanced spectral flatness in traveling-wave semiconductor optical amplifiers
Authors: Verma Priyanka , Singh Sukhbir 
Published: August 2024

Abstract
This paper proposes a method for generating an optical frequency comb (OFC) using the cross-polarization modulation (XPolM) effect in a traveling-wave semiconductor optical amplifier (TW-SOA). The TW-SOA acted as a lumped amplifier, enabling pulse generation within the comb. The proposed method of OFC generation achieved a comb spectrum with 51 lines and a maximum power deviation of 1.8 dB, indicating excellent spectral flatness. The proposed approach effectively utilized XPolM in a TW-SOA to create broad flat OFCs. The effectiveness of XPolM depends on various SOA parameters, such as pump and signal powers, and the confinement factor. To understand the XPolM-enabled OFC behavior, various parameters, such as input polarization, bias current, SOA confinement factor, and carrier density, have been optimized. These parameters significantly influenced the generated comb spectrum. This study also provides valuable insights into optimizing comb characteristics through theoretical analysis. The proposed OFC generation was simulated using an OptiSystem simulator. This has paved the way for the potential use of the comb as a multichannel source in various optical devices.
Temperature induced A1 to B2 structural and magnetic transition in FeRh thin film
Authors: Merkel D G , Gracheva M A , Radnóczi G Z , Hegedűs G , Nagy D L , Horváth Z E , Lengyel A 
Published: August 2024

Abstract
The Fe-Rh system offers a diverse range of magnetic phases, making it promising for energy-efficient magnetic devices. A periodic, chemically homogeneous, isotope-periodic nFeRh/57FeRh multilayer system was deposited on a MgO(100) substrate via molecular beam epitaxy, and annealed at various temperatures and durations. To gain deeper insights into the A1 to B2 structural and magnetic transitions, non-destructive techniques such as x-ray diffraction, conversion electron Mössbauer spectroscopy, and neutron reflectometry were employed. The qualitative and quantitative analysis revealed insights into the underlying mechanisms of the transformation from the A1 phase to the B2 phase were described, including the variation of the lattice parameters, grain sizes and hyperfine parameters. Neutron reflectometry revealed no significant long-range diffusion during the phase transition, suggesting a local interchange of neighbouring atoms.
Optimization and ranking of the input parameter settings of sustainable grinding using cashew nut shell liquid as cutting fluid
Authors: Usgaonkar Gajesh G S , Prabhu Gaonkar Rajesh S 
Published: August 2024

Abstract
The current work advocates the use of Cashew Nut Shell Liquid/Oil (CNSL), an oil extract of the leftover cashew nut shells, as a novel environment-friendly cutting fluid in sustainable machining operations. The tribological characteristics of CNSL obtained on a pin-on-disc tribometer are found to be better compared to the traditionally used cutting fluid. Experiments are conducted on the surface grinder with EN8 material, considering input parameters, such as cutting fluid type, grinder speed and grade, work speed, and depth of cut, with Surface Roughness (Ra) and Grinding Temperature (Temp) being the responses. Input parameter optimization is performed using Taguchi’s statistical models. A total of 36 investigative and six validation experiments are conducted, and a prediction model is proposed. When Ra and Temp are optimized simultaneously, the prediction value of Ra is 0.071 μm, and the corresponding value of Temp is 31.6 °C for which the experimental values are 0.072 μm and 32 °C respectively. This work also applies the TODIM (TOmada de Decisao Interativa Multicriterio, in the Portuguese language), a multi-attribute decision-making method for ranking the input parameter settings. The study reveals that the performance of CNSL is better than that of a traditional cutting fluid, and the TODIM method can be successfully applied to rank the input parameter settings.
3D printed heterogeneous paediatric head and adult thorax phantoms for linear accelerator radiotherapy quality assurance: from fabrication to treatment delivery
Authors: Bustillo John Paul O , Posadas Julia Rebecca D , Mata Jacob L , Inocencio Elrick T , Rosenfeld Anatoly B , Lerch Michael L F 
Published: August 2024

Abstract

Objective. This study aims to design and fabricate a 3D printed heterogeneous paediatric head phantom and to customize a thorax phantom for radiotherapy dosimetry. Approach. This study designed, fabricated, and tested 3D printed radiotherapy phantoms that can simulate soft tissue, lung, brain, and bone. Various polymers were considered in designing the phantoms. Polylactic acid+, nylon, and plaster were used in simulating different tissue equivalence. Dimensional accuracy, and CT number were investigated. The phantoms were subjected to a complete radiotherapy clinical workflow. Several treatment plans were delivered in both the head and the thorax phantom from a simple single 6 MV beam, parallel opposed beams, and five-field intensity modulated radiotherapy (IMRT) beams. Dose measurements using an ionization chamber and radiochromic films were compared with the calculated doses of the Varian Eclipse treatment planning system (TPS). Main results. The fabricated heterogeneous phantoms represent paediatric human head and adult thorax based on its radiation attenuation and anatomy. The measured CT number ranges are within −786.23 ± 10.55, 0.98 ± 3.86, 129.51 ± 12.83, and 651.14 ± 47.76 HU for lung, water/brain, soft tissue, and bone, respectively. It has a good radiological imaging visual similarity relative to a real human head and thorax depicting soft tissue, lung, bone, and brain. The accumulated dose readings for both conformal radiotherapy and IMRT match with the TPS calculated dose within ±2% and ±4% for head and thorax phantom, respectively. The mean pass rate for all the plans delivered are above 90% for gamma analysis criterion of 3%/3 mm. Significance and conclusion. The fabricated heterogeneous paediatric head and thorax phantoms are useful in Linac end-to-end radiotherapy quality assurance based on its CT image and measured radiation dose. The manufacturing and dosimetry workflow of this study can be utilized by other institutions for dosimetry and trainings.
Microfluidic systems for modeling digestive cancer: a review of recent progress
Authors: Razavi ZahraSadat , Soltani Madjid , Pazoki-Toroudi Hamidreza , Dabagh Mahsa 
Published: August 2024

Abstract

Purpose. This review aims to highlight current improvements in microfluidic devices designed for digestive cancer simulation. The review emphasizes the use of multicellular 3D tissue engineering models to understand the complicated biology of the tumor microenvironment (TME) and cancer progression. The purpose is to develop oncology research and improve digestive cancer patients’ lives. Methods. This review analyzes recent research on microfluidic devices for mimicking digestive cancer. It uses tissue-engineered microfluidic devices, notably organs on a chip (OOC), to simulate human organ function in the lab. Cell cultivation on modern three-dimensional hydrogel platforms allows precise geometry, biological components, and physiological qualities. The review analyzes novel methodologies, key findings, and technical progress to explain this field’s advances. Results. This study discusses current advances in microfluidic devices for mimicking digestive cancer. Micro physiological systems with multicellular 3D tissue engineering models are emphasized. These systems capture complex biochemical gradients, niche variables, and dynamic cell–cell interactions in the tumor microenvironment (TME). These models reveal stomach cancer biology and progression by duplicating the TME. Recent discoveries and technology advances have improved our understanding of gut cancer biology, as shown in the review. Conclusion. Microfluidic systems play a crucial role in modeling digestive cancer and furthering oncology research. These platforms could transform drug development and treatment by revealing the complex biology of the tumor microenvironment and cancer progression. The review provides a complete summary of recent advances and suggests future research for field professionals. The review’s major goal is to further medical research and improve digestive cancer patients’ lives.