bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self-consistent modelling of the dust component in protoplanetary and circumplanetary disks: the case of PDS 70
Authors: Portilla-Revelo B. , Kamp I. , Rab Ch. , van Dishoeck E. F. , Keppler M. , Min M. , Muro-Arena G. A. 
Published: November 2021

Context.Direct observations of young stellar objects are important to test established theories of planet formation. PDS 70 is one of the few cases where robust evidence favours the presence of two planetary mass companions inside the gap of the transition disk. Those planets are believed to be going through the last stages of accretion from the protoplanetary disk, a process likely mediated by a circumplanetary disk (CPD).Aims.We aim to develop a three-dimensional radiative transfer model for the dust component of the PDS 70 system which reproduces the system’s global features observed at two different wavelengths: 855 μm with the Atacama large millimeter/submillimeter array (ALMA) and 1.25 μm with the Spectro-polarimetric high-contrast exoplanet research instrument at the Very large telescope (VLT/SPHERE). We use this model to investigate the physical properties of the planetary companion PDS 70 c and its potential circumplanetary disk.Methods.We base our modelling process on published ALMA and VLT/SPHERE observations of the dust continuum emission at 855 and 1.25 μm, respectively. We selected initial values for the physical properties of the planet and CPD through appropriate assumptions about the nature and evolutionary stage of the object. We modified the properties of the protoplanetary disk iteratively until the predictions retrieved from the model were consistent with both data sets. Simulations were carried out with the three-dimensional radiative transfer codeMCMax3D.Results.We provide a model that jointly explains the global features of the PDS 70 system seen in sub-millimetre and polarised-scattered light. Our model suggests that spatial segregation of dust grains is present in the protoplanetary disk. The sub-millimetre modelling of the PDS 70 c source favours the presence of an optically thick CPD and places an upper limit on its dust mass of 0.7M⊕. Furthermore, analysis of the thermal structure of the CPD demonstrates that the planet luminosity is the dominant heating mechanism of dust grains inside 0.6 au from the planet, while heating by stellar photons dominates at larger planetocentric distances.Conclusions.A CPD surrounding the planetary-mass companion PDS 70 c is a plausible scenario to explain the substructure observed with ALMA. The heating feedback from the protoplanetary disk has an non-negligible effect on the equilibrium temperature of dust grains in the outskirts of the CPD. The connection between the CPD properties and the planet mass still depends on a series of key assumptions. Further observations with high spatial and spectral resolution also for the gas component of the CPD are required to break the degeneracy between the properties of the planet and the disk.
Gaia-ESO Survey: Detailed elemental abundances in red giants of the peculiar globular cluster NGC 1851
Authors: Tautvaišienė G. , Drazdauskas A. , Bragaglia A. , Martell S. L. , Pancino E. , Lardo C. , Mikolaitis Š. , Minkevičiūtė R. , Stonkutė E. , Ambrosch M. , Bagdonas V. , Chorniy Y. , Sanna N. , Franciosini E. , Smiljanic R. , Randich S. , Gilmore G. , Bensby T. , Bergemann M. , Gonneau A. , Guiglion G. , Carraro G. , Heiter U. , Korn A. , Magrini L. , Morbidelli L. , Zaggia S. 
Published: November 2021

Context. NGC 1851 is one of several globular clusters for which multiple stellar populations of the subgiant branch have been clearly identified and a difference in metallicity detected. A crucial piece of information on the formation history of this cluster can be provided by the sum of A(C+N+O) abundances. However, these values have lacked a general consensus thus far. The separation of the subgiant branch can be based on age and/or A(C+N+O) abundance differences.
Aims. Our main aim was to determine carbon, nitrogen, and oxygen abundances for evolved giants in the globular cluster NGC 1851 in order to check whether or not the double populations of stars are coeval.
Methods. High-resolution spectra, observed with the FLAMES-UVES spectrograph on the ESO VLT telescope, were analysed using a differential model atmosphere method. Abundances of carbon were derived using spectral synthesis of the C2 band heads at 5135 and 5635.5 Å. The wavelength interval 6470−6490 Å, with CN features, was analysed to determine nitrogen abundances. Oxygen abundances were determined from the [O I] line at 6300 Å. Abundances of other chemical elements were determined from equivalent widths or spectral syntheses of unblended spectral lines.
Results. We provide abundances of up to 29 chemical elements for a sample of 45 giants in NGC 1851. The investigated stars can be separated into two populations with a difference of 0.07 dex in the mean metallicity, 0.3 dex in the mean C/N, and 0.35 dex in the mean s-process dominated element-to-iron abundance ratios [s/Fe]. No significant difference was determined in the mean values of A(C+N+O) as well as in abundance to iron ratios of carbon, α- and iron-peak-elements, and of europium.
Conclusions. As the averaged A(C+N+O) values between the two populations do not differ, additional evidence is given that NGC 1851 is composed of two clusters, the metal-rich cluster being by about 0.6 Gyr older than the metal-poor one. A global overview of NGC 1851 properties and the detailed abundances of chemical elements favour its formation in a dwarf spheroidal galaxy that was accreted by the Milky Way.
The Data Acquisition System for the ATLAS Phase-II Tile Calorimeter Demonstrator
Authors: Argos Fernando Carrió 
Published: November 2021

The Tile Calorimeter (TileCal) is the central hadronic calorimeter of the ATLAS experiment at Large Hadron Collider (LHC). The TileCal readout system consists of about 10,000 channels. In 2025, the LHC will be upgraded leading into the High Luminosity LHC (HL-LHC). The HL-LHC will be capable to deliver an instantaneous luminosity up to seven times compared to the LHC nominal luminosity. The TileCal Phase-II upgrade will replace the majority of the on-detector and off-detector electronics using a new readout schema for the HL-LHC era. The on-detector electronics will digitize and transmit calorimeter signals to the off-detector electronics at the bunch crossing frequency. In the counting rooms, the off-detector electronics will store the digitized samples in pipelined buffers and compute reconstructed trigger objects for the first level of trigger.The TileCal Phase-II upgrade project has undertaken an extensive R&D program which includes the development of a Demonstrator module to evaluate the performance of the new clock and readout architecture for the HL-LHC. A Demonstrator module containing the upgrade on-detector readout electronics was built, tested during several test beam campaigns, and inserted into the ATLAS experiment. The Demonstrator module is operated and read out using a Tile PreProcessor (TilePPr) Demonstrator which enables backward compatibility with the present ATLAS Trigger and Data AcQuisition and the Timing, Trigger and Command systems.This contribution describes the components of the clock distribution and data acquisition system for the Demonstrator module, and its implementation in the ATLAS experiment.
The VINON-LOCA test facility: exploring the LOCA phenomenology through an out-of-pile thermal sequence on irradiated pressurized fuel rod
Authors: Biard B. , Colin C. , Bernard S. , Marty V. , Volle G. , Martin F. , Charmasson P. , Ronné K. , Moysan-Lavoine I. , Ferrandis J.-Y. , Schoepff V. , Amoyal G. , Fédérici E. 
Published: November 2021

Since the out-of-pile semi-integral tests performed at Studsvik in 2011 for the NRC [1] and the Halden Loss-Of-Coolant Accident (LOCA) test series IFA-650 [2], a major safety interest has raised for Fuel Fragmentation, Relocation and Dispersal (FFRD) during a LOCA sequence. In addition to the characteristics of the fuel ejected from the rod after the clad failure, the fuel behaviour before the clad failure is still to be investigated, especially its fragmentation and its possible relocation within the rod during the clad ballooning phase. Furthermore, the chronology and the sequencing of these phenomena is of particular interest.
For this purpose, the VINON-LOCA program, lying in the framework of a trilateral agreement between EDF, Framatome and CEA, is aimed at performing Out-Of-Pile heating tests on irradiated repressurized fuel rods, reproducing a typical Loss Of Coolant Accident thermal sequence. The VINON-LOCA experimental set-up is located in the so-called VERDON lab of the LECA-STAR hot cell complex. This lab was dedicated to the VERDON-ISTP program [3]. The VINON-LOCA set-up is thus largely instrumented for addressing not only these FFRD topics, but also Fission Gas Release (FGR), combining both online measurement (gamma stations, gamma camera, acoustic sensor, pressure, temperatures, flow meters, microGC…), and preand post-test characterization (gamma scanning, tomography, metrology, fuel fragments weighing and sieving, gas analyses…).
An extensive and substantial qualification campaign has been performed to validate the furnace design regarding the desired test conditions, and to qualify the instrumentation. Following some preliminary modelling and calculations, it has included tests on an out-of-cell twin mockup and tests on dummy inactive rods in the hot cell. This allowed achieving successfully the first experimental qualification test of the program end of 2019 on an irradiated UO2 fuel rodlet. A second irradiated experiment is planned with increased instrumentation capabilities, notably a 2D gamma camera for online fuel motion detection.
A High-Granularity Timing Detector for the Phase-II upgrade of the ATLAS Calorimeter system: detector concept, description and R&D and beam test results
Authors: Imam H. 
Published: November 2021

The particle flux increase (pile-up) at the HL-LHC with luminosities of L = 7.5 × 1034 cm−2 s−1 will have a significant impact on the reconstruction of the ATLAS detector and on the performance of the trigger. The forward region and the end-cap where the internal tracker has poorer longitudinal track impact parameter resolution, and where the liquid argon calorimeter has coarser granularity, will be significantly affected. A High Granularity Time Detector (HGTD) is proposed to be installed in front of the LAr end-cap calorimeter for the mitigation of the pileup effect, as well as measurement of luminosity.
It will have coverage of 2.4 to 4.0 from the pseudo-rapidity range. Two dual-sided silicon sensor layers will provide accurate timing information for minimum-ionizing particles with a resolution better than 30 ps per track (before irradiation), for assigning each particle to the correct vertex. The readout cells are about 1.3 mm × 1.3 mm in size, which leads to a high granular detector with 3 million channels. The technology of low-gain avalanche detectors (LGAD) with sufficient gain was chosen to achieve the required high signal-to-noise ratio. A dedicated ASIC is under development with some prototypes already submitted and evaluated. The requirements and general specifications of the HGTD will be maintained and discussed. R&D campaigns on the LGAD are carried out to study the sensors, the related ASICs and the radiation hardness. Both laboratory and test beam results will be presented.
Using a co-created transdisciplinary approach to explore the complexity of air pollution in informal settlements
Authors: West Sarah E. , Bowyer Cressida J. , Apondo William , Büker Patrick , Cinderby Steve , Gray Cindy M. , Hahn Matthew , Lambe Fiona , Loh Miranda , Medcalf Alexander , Muhoza Cassilde , Muindi Kanyiva , Njoora Timothy Kamau , Twigg Marsailidh M. , Waelde Charlotte , Walnycki Anna , Wainwright Megan , Wendler Jana , Wilson Mike , Price Heather D. 
Published: November 2021

AbstractWe present novel co-created transdisciplinary research that uses arts and humanities methods to explore air pollution in an informal settlement (Mukuru) in Nairobi, Kenya. Air pollution is a well-documented major human health issue, but despite many air pollution reduction interventions designed to improve health, these are frequently ineffective. Often this is because they fail to account for local knowledge, cultural practices and priorities of the intended recipients. Designing solutions therefore requires in-depth exploration of relevant issues with stakeholders. Researchers worked collaboratively with local residents to develop a range of methods to explore understandings of air pollution including interviews, storytelling, participatory mapping and theatre. Together, we uncovered contrasting definitions of air pollution, differing perceptions of who was responsible for enacting solutions, and overall a view that air pollution cannot be seen in isolation from the other issues faced by settlement residents. The methods used also allowed us to communicate about the topic with a wide audience. While we acknowledge that this research approach is more time consuming than traditional approaches, we urge other researchers wishing to address multifactorial problems, such as air pollution to use a mixture of qualitative, participatory and creative methods to engage with a wide range of stakeholders to elicit new and unexpected understandings that may not otherwise emerge.
The genetic basis of the root economics spectrum in a perennial grass
Authors: Chen Weile , Wu Yanqi , Fritschi Felix B. , Juenger Thomas E. 
Published: November 2021

Significance
Plants have evolved diverse root form and function across the Earth’s environment, yet only certain types of trait combinations have proved evolutionarily viable. Using a genetic mapping population of the native perennial switchgrass, our study demonstrates multiple genetic linkages among root morphology, growth, and turnover. Switching alleles derived from southern-origin ecotypes to alleles from northern-origin ecotypes increases root turnover but reduces tissue investment in root length construction. The genetic trade-off between construction and turnover likely facilitates the local adaptation of root strategy along the warm to cold climatic gradients of the species range. In practice, our study provides the genetic evidence that increasing switchgrass yield for bioenergy does not directly conflict with enhancing its root-derived carbon sequestration.
How does Internet of Things (IOT) affect travel experience?
Authors: Hu Meng-yun , Pantano Eleonora , Stylos Nikolaos 
Published: November 2021

Abstract

This chapter is a conceptual work by Mengyun Hu, Eleonora Pantano and Nikolaos Stylos addressing the subject of the Internet of Things (IoT) technologies and how these have impacted on the reformulation of services provided and received. In this chapter, the authors suggest that the application of IoT has a significant impact on understanding the tourist experience, since it can reshape travelling experiences throughout the entire trip; they conclude with directions for both academics and practitioners in several tourism fields, such as destination management, hospitality, transportation and intermediaries.
US tourists' food neophobia and their local food experiences in France and Italy.
Authors: Choe Ja Young 
Published: November 2021

Abstract

This study has three major objectives; the first is to explore whether tourists have different levels of food neophobia according to their sociodemographics; the second is to investigate if differences in tourists' local food consumption values exist among different food neophobia groups (FNGs); and the third is to examine whether differences in tourists' behavioural intention to go back to a destination for food tourism exist among different FNGs. This study expects that destination marketers, hospitality businesses and tour operators can achieve a competitive advantage by understanding the concept of food neophobia and its associations with tourists' sociodemographics and local food experiences in a destination. In particular, this study will focus on US tourists' local food perception experiences in France and Italy.
Quantization ambiguities and the robustness of effective descriptions of primordial perturbations in hybrid loop quantum cosmology
Authors: Elizaga Navascués Beatriz , Mena Marugán Guillermo A 
Published: November 2021

Abstract
We study the imprint that certain quantization ambiguities may leave in effective regimes of the hybrid loop quantum description of cosmological perturbations. More specifically, in the case of scalar perturbations we investigate how to reconstruct the Mukhanov–Sasaki field in the effective regime of loop quantum cosmology, taking as starting point for the quantization a canonical formulation in terms of other perturbative gauge invariants that possess different dynamics. This formulation of the quantum theory, in terms of variables other than the Mukhanov–Sasaki ones, is crucial to arrive at a quantum Hamiltonian with a good behavior, eluding the problems with ill defined Hamiltonian operators typical of quantum field theories. In the reconstruction of the Mukhanov–Sasaki field, we ask that the effective Mukhanov–Sasaki equations adopt a similar form and display the same Hamiltonian structure as the classical ones, a property that has been widely assumed in loop quantum cosmology studies over the last decade. This condition actually restricts the freedom inherent to certain quantization ambiguities. Once these ambiguities are removed, the reconstruction of the Mukhanov–Sasaki field naturally identifies a set of positive-frequency solutions to the effective equations, and hence a choice of initial conditions for the perturbations. Our analysis constitutes an important and necessary test of the robustness of standard effective descriptions in loop quantum cosmology, along with their observational predictions on the primordial power spectrum, taking into account that they should be the consequence of a more fundamental quantum theory with a well-defined Hamiltonian, in the spirit of Dirac’s long-standing ideas.
High resolution 3D ultrasonic breast imaging by time-domain full waveform inversion
Authors: Lucka Felix , Pérez-Liva Mailyn , Treeby Bradley E , Cox Ben T 
Published: November 2021

Abstract
Ultrasound tomography (UST) scanners allow quantitative images of the human breast’s acoustic properties to be derived with potential applications in screening, diagnosis and therapy planning. Time domain full waveform inversion (TD-FWI) is a promising UST image formation technique that fits the parameter fields of a wave physics model by gradient-based optimization. For high resolution 3D UST, it holds three key challenges: firstly, its central building block, the computation of the gradient for a single US measurement, has a restrictively large memory footprint. Secondly, this building block needs to be computed for each of the 103–104 measurements, resulting in a massive parallel computation usually performed on large computational clusters for days. Lastly, the structure of the underlying optimization problem may result in slow progression of the solver and convergence to a local minimum. In this work, we design and evaluate a comprehensive computational strategy to overcome these challenges: firstly, we exploit a gradient computation based on time reversal that dramatically reduces the memory footprint at the expense of one additional wave simulation per source. Secondly, we break the dependence on the number of measurements by using source encoding (SE) to compute stochastic gradient estimates. Also we describe a more accurate, TD-specific SE technique with a finer variance control and use a state-of-the-art stochastic LBFGS method. Lastly, we design an efficient TD multi-grid scheme together with preconditioning to speed up the convergence while avoiding local minima. All components are evaluated in extensive numerical proof-of-concept studies simulating a bowl-shaped 3D UST breast scanner prototype. Finally, we demonstrate that their combination allows us to obtain an accurate 442 × 442 × 222 voxel image with a resolution of 0.5 mm using Matlab on a single GPU within 24 h.
Biological thermometer based on the temperature sensitivity of magnetic nanoparticle paraSHIFT
Authors: Guo Silin , Yi Wentong , Liu Wenzhong 
Published: November 2021

Abstract
In the paper, the temperature dependence of magnetic nanoparticle (MNP) paramagnetic chemical shift (paraSHIFT) was studied by magnetic resonance (MR) spectroscopy. Based on it, iron oxide MNPs are considered as MR shifting probes for determining the temperature in liquids. With the increase in measurement temperature of the MNP reagent with MNPs, the decrease of MNP magnetization would make the peak of spectroscopy shift to the higher chemical shift area. The peak shift is related to the magnetic susceptibility of MNPs, which can be determined by MR frequency as a function of temperature and particle size. Experiments on temperature-dependent chemical shifts are performed for MNP samples with different core sizes and the estimated temperature accuracy can achieve 0.1 K. Combined with the contrast effect of magnetic nanoparticles in magnetic resonance imaging at 3 T, this technology can realize temperature imaging.
Preparation and disinfection properties of graphene oxide/trichloroisocyanuric acid disinfectant
Authors: Jiang Lili , Xu Su , Yu Haitao , Cui Qi , Cao Rui 
Published: November 2021

Abstract
Due to the impact of the new crown epidemic in recent years, disinfectants have played an increasingly important role, so the research and development of new high-efficiency nano-disinfectants are urgent issues. In this study, graphene oxide (GO) was first prepared by the modified Hummer method. Then, the GO/trichloroisocyanuric acid (TCCA) composite was prepared by loading TCCA into GO with the blending method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy and atomic force microscopy were used to characterize the composite. The results showed that TCCA was successfully loaded on the surface of GO or intercalated among GO layers. Next, the antibacterial performance of the composite against Escherichia coli and Staphylococcus aureus was tested by the 96-well plate assay. A bactericidal kinetic curve, bacterial inhibition tests, and the mechanism of bacterial inhibition were discussed. The results showed that the minimum inhibitory concentration (MIC) of the GO/TCCA composite (GO:TCCA ratio = 1:50) was 327.5 μg ml−1 against E. coli and 655 μg ml−1 against S. aureus. At the MIC, the inhibition rate of the GO/TCCA composite exceeded 99.46% against E. coli and 99.17% against S. aureus. The bactericidal kinetic curves indicate that the GO/TCCA composite has an excellent bactericidal effect against E. coli and S. aureus.
All-inorganic perovskite quantum dots-based electrospun polyacrylonitrile fiber for ultra-sensitive trace-recording
Authors: Li Yanyan , Shen Lifan , Pun Edwin Yue Bun , Lin Hai 
Published: November 2021

Abstract
All-inorganic dual-phase CsPbBr3-Cs4PbBr6 quantum dots (CPB QDs)-based polyacrylonitrile (PAN) fiber synthesized by supersaturated recrystallization and electrospinning technique possesses characteristics of homogeneous morphology, high crystallinity and solution sensitivity. Under 365 nm laser excitation, CPB@PAN fiber exhibits surprising trace-recording capability attributing to the splash-enhanced fluorescence (FL) performance with a narrow-band emission at 477–515 nm. In the process of ethanol anhydrous (EA) and water splashing, the CPB@PAN fiber presents conspicuous blue and green emission when contacting with EA and water, and maintains intense blue and green FL for more than 4 months. These experimental and theoretical findings provide a facile technology for the development of biological protection display, biotic detection and moisture-proof forewarning based on the trace-recording performance of CPB@PAN fiber.