bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of ESPRESSO’S high-resolution 4 × 2 binning for characterising intervening absorbers towards faint quasars
Authors: Berg Trystyn A. M. , Cupani Guido , Figueira Pedro , Mehner Andrea
Published: May 2022

As of October 2021 (Period 108), the European Southern Observatory (ESO) offers a new mode of the ESPRESSO spectrograph designed to use the high-resolution grating with 4 × 2 binning (spatial by spectral; HR42 mode), with the specific objective of observing faint targets with a single Unit Telescope at Paranal. We validated the new HR42 mode using four hours of on-target observations of the quasar J0003-2603, known to host an intervening metal-poor absorber along the line of sight. The capabilities of the ESPRESSO HR42 mode (resolving power R ≈ 137 000) were evaluated by comparing them to a UVES spectrum of the same target with a similar integration time but lower resolving power (R ≈ 48 000). For both data sets, we tested the ability to decompose the velocity profile of the intervening absorber using Voigt profile fitting and extracted the total column densities of C IV, N I, Si II, Al II, Fe II, and Ni II. With ≈3× the resolving power and ≈2× lower signal-noise ratio (S/N) for a nearly equivalent exposure time, the ESPRESSO data is able to just as accurately characterise the individual components of the absorption lines as the comparison UVES data, but it has the added bonus of identifying narrower components not detected by UVES. For UVES to provide similar spectral resolution (R > 100 000; 0.3″ slit) and the broad wavelength coverage of ESPRESSO, the Exposure Time Calculator (ETC) supplied by ESO estimates 8 h of exposure time spread over two settings, requiring double the time investment compared to that of ESPRESSO’s HR42 mode whilst not properly sampling the UVES spectral resolution element. Thus, ESPRESSO’s HR42 mode offers nearly triple the resolving power of UVES (0.8″ slit to match typical ambient conditions at Paranal) and provides more accurate characterisation of quasar absorption features for an equivalent exposure time.
Properties of the ionisation glitch
Authors: Houdayer Pierre S. , Reese Daniel R. , Goupil Marie-Jo
Published: May 2022

Aims. In the present paper, we aim to constrain the properties of the ionisation region of a star from the oscillation frequency variation (a so-called glitch) caused by rapid structural variations in this very region. In particular, we seek tof avoid the use of calibration based on stellar models, thus providing a truly independent estimate of these properties. These include both the helium abundance and other physical quantities that can have a significant impact on the oscillation frequencies, such as the electronic degeneracy parameter or the extent of the ionisation region.

Methods. Building on previous findings, we applied structural perturbations of the ionisation zone to the wave equation for radial oscillations in an isentropic region. The resulting glitch model is thus able to exploit the information contained in the fast frequency oscillation caused by the helium ionisation but also that in the slow trend accompanying the ionisation of hydrogen. This information can be directly expressed in terms of parameters related to the helium abundance, electronic degeneracy, and the extent of the ionisation region, respectively.

Results. Using Bayesian inference, we show that substantial recovery of the properties at the origin of the glitch is possible. We find a degeneracy between the helium abundance and the electronic degeneracy, which particularly affects the helium estimate. Extending the method to cases where the glitch is subject to contamination (e.g., surface effects), we note the importance of the slow glitch trend associated with hydrogen ionisation. We propose the use of a Gaussian process to disentangle the frequency glitch from surface effects.
Cloud-cloud collision and star formation in G323.18+0.15
Authors: Ma Yingxiu , Zhou Jianjun , Esimbek Jarken , Baan Willem , Li Dalei , He Yuxin , Tang Xindi , Ji Weiguang , Zhou Dongdong , Wu Gang , Xu Ye
Published: May 2022

We studied the cloud-cloud collision candidate G323.18+0.15 based on signatures of induced filaments, clumps, and star formation. We used archival molecular spectrum line data from the SEDIGISM 13CO (J = 2−1) survey, from the Mopra southern Galactic plane CO survey, and infrared to radio data from the GLIMPSE, MIPS, Hi-GAL, and SGPS surveys. Our new result shows that the G323.18+0.15 complex is 3.55 kpc away from us and consists of three cloud components, G323.18a, G323.18b, and G323.18c. G323.18b shows a perfect U-shape structure, which can be fully complemented by G323.18a, suggesting a collision between G323.18a and the combined G323.18bc filamentary structure. One dense compressed layer (filament) is formed at the bottom of G323.18b, where we detect a greatly increased velocity dispersion. The bridge with an intermediate velocity in a position-velocity diagram appears between G323.18a and G323.18b, which corresponds to the compressed layer. G323.18a plus G323.18b as a whole are probably not gravitationally bound. This indicates that high-mass star formation in the compressed layer may have been caused by an accidental event. The column density in the compressed layer of about 1.36 × 1022 cm−2 and most of the dense clumps and high-mass stars are located there. The average surface density of class I and class II young stellar objects (YSOs) inside the G323.18+0.15 complex is much higher than the density in the surroundings. The timescale of the collision between G323.18a and G323.18b is 1.59 Myr. This is longer than the typical lifetime of class I YSOs and is comparable to the lifetime of class II YSOs.
Water Sap flow and Soil Moisture Measurements for an Automatic Irrigation Control System
Authors: Chergaoui Sara , Alj Yassine Salih , Et-Taibi Bouali , Bourhnane Safae , Abid Mohamed Riduan
Published: May 2022

A sound water management requires accurate field data inquiry that can eventually allow for a proper control of the field’s irrigation. This work pro-poses an automatic irrigation control system that aims at optimizing the quantity of water needed for plants’ growth. The system consists of three key blocks: first, the continuous inquiry of the physical characteristics of the plant; second, the control unit to decide upon the actions to launch by the actuation unit; and third the actuation unit that sets parameters for pumps and valves. Conventional smart irrigation control systems use soil moister sensors which neglect the plant’s physiology as a monitoring factor, so this paper suggests the use of a sap flow sensor that accurately evaluates the plant’s condition; hence, decide upon the proper water distribution, illustrated with preliminary experimental results.
Numerical simulation of the advection-diffusion-reaction equation using finite difference and operator splitting methods: Application on the 1D transport problem of contaminant in saturated porous media
Authors: El Arabi Inasse , Chafi Anas , Alami Salaheddine Kammouri
Published: May 2022

The combined advection-diffusion-reaction (ADR) equation, which describe the transport problem of a contaminant in porous medium, does not generally admit an analytical solution. In general, when solving the ADR equation, the numerical methods (such as finite differences, finite elements, splitting), for most practical problems, the ADR equation is too difficult to solve analytically. The finite difference method is the oldest and most commonly used method for the numerical solution of this kind of equation. Although newer techniques, such as those based on finite elements and splitting are appropriate for the solution of equilibrium-type problems, the finite difference remains the most appropriate for the solution of time-dependent phenomena. The transport of a contaminant can also be written by the ADR equation; hence, our objective is to choose the most efficient method to study the 1D transport problem of a contaminant and its evolution in a porous medium. In this work, we will simulate the ADR equation using two different methods: those of finite difference and splitting ones. The numerical result will be compared with the analytical solution in order to discuss the stability and the convergence of each of them using those two different methods. In the end, we will show that the splitting technical method is more efficient for solving this kind of problems in comparison with the finite difference method despite the fact that the latter is the most widely used by researchers. The validation of the efficiency of this method, implemented in this simulation, is tested on a 1D-transport problem of contaminant in a saturated porous medium.
PQ Theory of SAP Filter in Photovoltaic System Connected to Three-Phase Grid and Controlled Nonlinear
Authors: Kabba A. , El Fadil H. , Yahya A. , Bentalhik I.
Published: May 2022

Currently, we are trying to improve electrical energy in the world. In practice, the use of switching devices is increased in the various applications. Non-linearity of loads has adverse effects on energy efficiency, power factor, etc. This increases the reactive power and oversizes the devices of the electrical installation. Several solutions are therefore proposed. Unlike passive filter, active filters work due to their small size. In this paper, work is done on the Parallel Active Power Filter (SAPF) using nonlinear control based on Lyapunov theory and PQ theory for attenuation of harmonics and reduction of imaginary power in operation of a photovoltaic system. The simulation of the circuits is implemented in MATLAB / SIMULINK. The measurements have been presented with or without SAPF filter. We start the article by modeling the different devices used, then an analysis of the PQ theory is carried out, carrying out simulations, results and interpretations. Finally, we end with a conclusion where we can say that the THD value of the source current reached is less than 5% imposed by the required standards.
Impact of the preprocessing block on the performance of the ΒCI system
Authors: Hamou Soukaina , Azami Hafida Idrissi , Agounad Said , Tarahi Ousama , Moufassih Mustapha
Published: May 2022

Electroencephalography (ΕΕG) is considered as one of the famous and efficient used methods in the Brain Computer Interface (ΒCI). This is due to its simplicity for implementation, low cost and being portable. The ΕΕG is a technique that examines the electrical activity of the brain using a non-invasive electrodes placed on the scalp. ΕΕG-based BCI system is constituted of five blocks: signal acquisition, preprocessing, feature extraction, classification and command block. In this paper, we will study the impact of the filter type and its order on the performance of the considered BCI system. This system is composed of: bandpass (ΒΡ) filter for the preprocessing step, Common Spatial Pattern (CSP) in the feature extraction block, and for the classification block, we used Support Vector Machine (SVΜ). The obtained results show a good improvement of the proposed BCI system. Indeed, the accuracy of this system can achieve 88.17% and the kappa coefficient is almost 0.76.
Theoretical and simulation study of pressure and temperature effect on the electronic states induced by the presence of a material defect in ZnO/ZnMgO MQWs
Authors: Baidri Abdelkader , Elamri Fatima Zahra , Ben-Ali Youssef , Falyouni Farid , Bria Driss
Published: May 2022

This work deals with a theoretical study of the effect of pressure and temperature on the electronic states induced by the presence of a material defect in ZnO/Zn1-XMgxO Multi-Quantum wells. To determine the transmission coefficient of our structure, we use a mathematical language very well known for composite materials that of the response theory, also called the green function. We demonstrate that the insertion of a material defect in the middle of the MQWs allows our systems to be like symmetrical systems and amplifies the electronic transmission of the defect state. Moreover, we found that the hydrostatic pressure increase induces a noticeable shift of the electronic state towards the lower energies due to the increase of the effective mass. This behavior will be reversed for the increase in the temperature. Our results were validated and compared with those of the literature. The change of position of the defect state allows us to use this structure as a regulable pressure and temperature sensor.
NFC/RFID sensor Tag for Wireless Temperature Monitoring in a Cold Chain
Authors: Nogues Estelle , Mackowiack Nicolas , Hamdoun Abdelaziz , Latrach Mohamed
Published: May 2022

This work presents the design and validation of a temperature sensor tag, which can be queried either by a cell phone using the NFC protocol or an HF RFID reader. It will easily ensure the cold chain failures and the product integrity. The proposed recording sensor can be placed on the packaging box to measure the temperature of the product. This allows to observe and store its evolution in order to guarantee the products quality and to respect the applicable provisions during transport. Thanks to a cell phone with the NFC, this recording data can be easily available, contrary to existing tags on the market. The design of tag is summed up as the choice of components, and the size of the antenna. Then a program for data recording and processing is developed using C language. Indeed, to have a triple gain of place, speed, and cost; an optimization of values recorded is operated. The overall tag size is 5.1x4x1.6 mm3, and its operation has been validated by performing in a real scenario: the temperature monitoring of a water bottle inside a bag for at least 50 minutes. The results of this test will be presented and discussed.
Deep learning approach for land use images classification
Authors: Douass S. , Ait Kbir M.
Published: May 2022

CNN (convolutional neural networks) are a category of neural networks that are majorly used for image classification and recognition. This Deep Learning (DL) technique is used to solve complex problems, particularly for environmental protection, its approaches have affected several domains without exception, geospatial world is one vised domain. In this paper we aim to classify aerial images of Tangier region, city located in north of Morocco, by using pixel based image classification with convolutional Neural Networks. Flickr API is used to get our test images dataset. These images are used as input to a pretrained network Resnet18, a small convolution neural network architecture, which is able to recognize 21 land use classes of images. Our methodology is based on the following steps, first we set up the data, and then we re-train the cited Deep Learning model (Transfer Learning) and perform a quick and visual verification, by generating a labeled map from the geotagged images, labels correspond to class provided by the CNN neural network.
Feature Selection: A Review and Comparative Study
Authors: Bouchlaghem Younes , Akhiat Yassine , Amjad Souad
Published: May 2022

Feature selection (FS) is an important research topic in the area of data mining and machine learning. FS aims at dealing with the high dimensionality problem. It is the process of selecting the relevant features and removing the irrelevant, redundant and noisy ones, intending to obtain the best performing subset of original features without any transformation. This paper provides a comprehensive review of FS literature intending to supplement insights and recommendations to help readers. Moreover, an empirical study of six well-known feature selection methods is presented so as to critically analyzing their applicability.
Study and design of an active magnetorquer actuator model for nanosatellites
Authors: El Fatimi Aziz , Addaim Adnane , Guennoun Zouhair
Published: May 2022

This paper focuses on the study and the design of an air core magnetorquer model dedicated to the 1U CubeSat (10×10×10 cm3). The objective is to obtain a solution which is able to provide accurate attitude control while having the smallest possible dimensions, electrical power, and total mass. To this end, the first part will provide theoretical mathematical knowledge on the laws of the coil to design an electromagnetic air core actuator. Then, this paper presents comparisons of the performances obtained by varying the type of material and the shape of the coil. Towards the end, the effect of temperature variation in LEO orbit is taken into consideration to predict the generated magnetic moment.
Design of a waveguide bandpass filter with inductive irises for a satellite application
Authors: Aghanim Amina , Lasri Rafik , Oulhaj Otman , Chekenbah Hamid
Published: May 2022

This paper presents a synthesis, design, and simulation of a bandpass rectangular waveguide filter with symmetrical transverse discontinuities operating in the X-band (WR90) with a central frequency of 11GHz, a fractional bandwidth of 3.1%, an undulation ripple of 0.014 dB inside the bandwidth, and a return loss level around 15 dB. The simulation is effectuated under the HFSS environment, where the results of the S-parameters in dB and degree were verified using a CST environment. The obtained results had proven the validity of the conception of our structure since it has shown a symmetrical aspect around the central frequency in both 3D simulators after optimizing the overall dimensions of the irises, also our study has proved that irises are a reliable way to design bandpass filters especially, where their dimensions mainly affect the filter response in terms of the return loss quantity, the insertion loss, and the filter’s bandwidth.
Contribution in Big Data Projects Management
Authors: Errezgouny Abderrachid , Cherkaoui Abdeljabbar
Published: May 2022

Nowadays, the necessity of the data becomes more attractive by companies in different areas (IT, space, automotive) who need to create and capture the value from the huge amounts of data generated from various sources. Many fields need to use this amount in the right way in real time with high level processing, this evolution is called Big Data (BD). In this case, to manage a BD project the specific tools like Machine Learning, Data Mining, and more are very important to achieve the customer satisfaction with the expected quality of services. The majority of BD projects fall due to the lack of managing skills and team training, also the sophisticated materials and technologies are required. This paper presents our contribution in the project management of BD based on other discussed methods like Project Management Body of Knowledge (PMBoK) and Agile approaches, and we use them to construct a rigid model for managing any project dedicated to work with BD.
Asymmetric Shunt Inductance Iris Rectangular Waveguide Filters for Satellite Communication Systems
Authors: Setti Hicham , Maimouni A. , Tribak A. , Souna O.
Published: May 2022

This paper presents the design, simulation and manufacture of two Asymmetrical filters based respectively on standard rectangular waveguides WR90 and WR75 in which resonant irises are inserted, operating respectively in the X-Band [9-11GHz] and Ku-Band [11-13GHz].The filter parameters were simulated by the MMM modal matching method (MMM) implemented in the Microwave-Wizard software, and that obtained by the CST-MWS software. The simulated results are in good agreement with those obtained by the experimental measurements.
La contraception à travers le monde
Authors: Christin-Maitre Sophie
Published: May 2022

Les dernières données concernant la contraception à travers le monde ont été publiées en 2019 par l’Organisation des Nations unies (ONU). Parmi les 1,9 milliard de femmes en âge de procréer (entre 15 et 49 ans), 1,1 milliard souhaitaient une contraception. Pourtant, 10 % d’entre elles n’utilisaient pas de méthode contraceptive, essentiellement en raison d’un manque d’accès à ces méthodes. Selon les continents, une grande disparité est observée dans l’utilisation des différentes méthodes contraceptives. La stérilisation féminine, ou contraception définitive, reste cependant la méthode majoritairement utilisée puisqu’elle représente 24 % des contraceptions. Des progrès sont nécessaires, en particulier dans l’éducation, pour améliorer la diffusion d’autres méthodes également efficaces, qui sont bien tolérées et possiblement réversibles.
Genetic Medicine for Hearing Loss: OTOF as Exemplar
Authors: Hickox Ann E. , Valero Michelle D. , McLaughlin James T. , Robinson Gregory S. , Wellman Jennifer A. , McKenna Michael J. , Sewell William F. , Simons Emmanuel J.
Published: May 2022

Abstract Millions of people worldwide have disabling hearing loss because one of their genes generates an incorrect version of some specific protein the ear requires for hearing. In many of these cases, delivering the correct version of the gene to a specific target cell
within the inner ear has the potential to restore cochlear function to enable high-acuity physiologic hearing. Purpose: In this review, we outline our strategy for the development of genetic medicines with the potential to treat hearing loss. We will use the example of otoferlin gene (OTOF)-mediated
hearing loss, a sensorineural hearing loss due to autosomal recessive mutations of the OTOF gene.
From Bench to Booth: Examining Hair Cell Regeneration Through an Audiologist's Scope
Authors: Lewis Rebecca M.
Published: May 2022

Abstract Damage to auditory hair cells is a key feature of sensorineural hearing loss due to aging, noise exposure, or ototoxic drugs. Though hair cell loss is permanent in humans, research in bird species led to the discovery that analogous hair cells of the avian basilar
papilla are able to regenerate after being damaged by ototoxic agents. Regeneration appears to occur through a combination of the mitotic expansion of a precursor population of supporting cells and direct transdifferentiation of supporting cells into functioning hair cells. This review will
synthesize the relevant anatomy and pathophysiology of sensorineural hearing loss, the historical observations that led to the genesis of the hair cell regeneration field, and perspectives on initial human hair cell regeneration trials.
Brachial Plexus Birth Palsy: Practical Concepts for Radiologists
Authors: González-Mantilla Pedro , Abril Angela , Bedoya Maria Alejandra
Published: May 2022

Brachial plexus birth palsy (BPBP) is classified as a preganglionic or postganglionic injury based on the site of injury. Most patients recover spontaneously and are followed up with clinical evaluation; however, permanent sequelae are not uncommon. For patients with persistent neurologic deficits, clinical and radiologic evaluation is crucial. Untreated BPBP can progress to significant sequelae, such as muscle contractures and glenohumeral dysplasia (GHD). Timely characterization of these entities based on different imaging modalities is a high priority for optimal patient outcomes. We describe the anatomy and pathogenesis, as well as the different imaging modalities involved in the evaluation and classification of BPBP and GHD.
Mario Campanacci, 1932-1999
Authors: Bazzocchi Alberto , Campanacci Laura , Aparisi Gómez Maria Pilar , Guglielmi Giuseppe
Published: May 2022

This history page in the series “Leaders in Musculoskeletal Radiology” is dedicated to the memory and achievements of the Italian scientist Mario Campanacci, whose name is connected to the medical eponym Jaffe-Campanacci syndrome and to the field and progress of musculoskeletal oncology.
Bi- and tetracritical phase diagrams in three dimensions
Authors: Aharony Amnon , Entin-Wohlman Ora , Kudlis Andrey
Published: May 2022

The critical behavior of many physical systems involves two competing n1- and n2-component order-parameters, S1 and S2, respectively, with n = n1 + n2. Varying an external control parameter g, one encounters ordering of S1 below a critical (second-order) line for g < 0 and of S2 below another critical line for g > 0. These two ordered phases are separated by a first-order line, which meets the above critical lines at a bicritical point, or by an intermediate (mixed) phase, bounded by two critical lines, which meet the above critical lines at a tetracritical point. For n = 1 + 2 = 3, the critical behavior around the (bi- or tetra-) multicritical point either belongs to the universality class of a non-rotationally invariant (cubic or biconical) fixed point, or it has a fluctuation driven first-order transition. These asymptotic behaviors arise only very close to the transitions. We present accurate renormalization-group flow trajectories yielding the effective crossover exponents near multicriticality.
Robust perpendicular magnetic anisotropy in Ce substituted yttrium iron garnet epitaxial thin films
Authors: Kuila Manik , Sagdeo Archna , Longchar Lanuakum A. , Choudhary R. J. , Srinath S. , Raghavendra Reddy V.
Published: May 2022

Cerium substituted yttrium iron garnet (Ce:YIG) epitaxial thin films are prepared on a gadolinium gallium garnet (GGG) substrate with pulsed laser deposition. It is observed that the films grown on a GGG(111) substrate exhibit perpendicular magnetic anisotropy (PMA) as compared to films grown on a GGG(100) substrate. The developed PMA is confirmed from a magneto-optical Kerr effect, bulk magnetization, and ferromagnetic resonance measurements. Furthermore, the magnetic bubble domains are observed in the films exhibiting PMA. The observations are explained in terms of the growth direction of Ce:YIG films and the interplay of various magnetic anisotropy terms. The observed PMA is found to be tunable with the thickness of the film, and a remarkable temperature stability of the PMA is observed in all the studied films of Ce:YIG deposited on a GGG(111) substrate.
Optoelectronic and mechanical properties of the orthogonal and tetragonal Cu2CdGe(SxSe1−x)4 semiconducting system via first principles methods
Authors: Barone V. T. , Dumre B. B. , Tuttle B. R. , Khare S. V.
Published: May 2022

We computationally investigate the tetragonal and orthorhombic Cu2CdGe(SxSe1−x)4 (0≤x≤1) alloy systems and study their mechanical and optoelectronic properties for photovoltaic applications using first principles density functional theory and beyond methods. Formation energies are all below −5.5 eV/f.u., decreasing with x. Energy vs strain calculations estimate the bulk moduli to be between 55 and 69 GPa, the shear moduli to be between 22 and 28 GPa, and Young's moduli to be between 59 and 74 GPa, all monotonically increasing with x. Optoelectronic properties are computed with the hybrid HSE06 functional. Bandgaps between 1.2 and 1.9 eV (increasing with x), low carrier masses in the (001) direction, and favorable optical absorption and reflectivity indicate that the alloys could be used as an absorber layer in solar cells. For a given value of x, the tetragonal system has higher elastic constants, a lower bandgap, and lower effective masses for both electrons and holes compared to the orthorhombic system. Further, the absorption coefficient near the peak of the standard AM 1.5 solar spectrum is calculated to be 5μm−1 larger for the tetragonal system than for the orthorhombic system. These considerations lead to the conclusion that the tetragonal system shows promise as an absorber material for both single-junction and tandem solar cells.
Heating of liquid substrate by low-pressure sputtering plasma
Authors: Patel Kamakshi , Sergievskaya Anastasiya , Chauhan Samir , Konstantinidis Stephanos
Published: May 2022

The heating of the liquid substrate by low-pressure (∼1 Pa) sputtering plasma has been investigated by in situ temperature measurements. The combination of “green” non-toxic solvent, castor oil, copper target, and direct current magnetron sputtering was chosen as a model system. The temperature increase induced by plasma was registered with two thermocouples placed immediately under the liquid surface and in the bulk solution. The effect of the working gas pressure and sputter power was studied. It was shown that the liquid temperature increases at a rate of up to 1 °C/min, depending on the sputtering conditions. The experimental data were compared with numerical calculations and COMSOL simulation. Provided information is essential data for the detailed explanation of the formation of nanoparticles during sputtering onto liquids, a clean approach for production of colloidal solutions of “naked” nanoparticles.
On the aerodynamic loads and flow statistics of airfoil with deformable vortex generators
Authors: Gong Pengyao , Aju Emmanuvel Joseph , Jin Yaqing
Published: May 2022

The aerodynamic performances and flow statistics for a Delft University-91-W2-250 airfoil with deformable vortex generators (DVG) were experimentally studied in a wind tunnel across various angle of attacks and wind speeds. A high-resolution force sensor was used to measure the time-averaged lift force, while a planar particle image velocimetry system was applied to characterize the mean velocity and vortex shedding over airfoil surface. The results highlighted that, similar to conventional rigid vortex generators (RVG), DVG can effectively enhance lift coefficient after the stall angle of airfoil with clean surface under low incoming winds. However, the deformation of DVGs increased with the growth of wind speed; this suppressed the effectiveness of wake mixing where the aerodynamic performance of DVGs gradually converged to clean surface configurations. The flow measurements demonstrated that the deformation of DVG can lead to significant decrease in near-wall flow velocities close to the airfoil trailing edge and generate more dispersed vorticity distributions. To further investigate the linkage between DVG deformation and its wake mixing effectiveness, complementary tomographic particle image velocimetry measurements were conducted. The results indicated that the vorticity strength presented monotonic decay with the bending angle of DVG within both near and intermediate wake regions. The capability of DVGs passively adjusts their bending angle, and therefore, the airfoil lift coefficients provide a novel approach to reduce aerodynamic load fluctuations for aircraft within unsteady flows.
Poor confinement in stellarators at high energy
Authors: White Roscoe , Bierwage Andreas , Ethier Stephane
Published: May 2022

High-energy particle resonances can modify particle distributions and even cause significant particle loss. Resonances can be present in any toroidal confinement device and can easily be found numerically. Many stellarators have weak magnetic shear so that large islands and large chaotic regions can be produced by resonant perturbations with small amplitudes. While the choice of the field line helicity profile in the plasma can limit the presence of resonances at low particle energy, the resonance location is energy-dependent, and they can move into the plasma at higher energy. If resonances match the toroidal variation of the equilibrium, they can produce wide islands in the phase space of orbits even in the absence of perturbations due to instabilities. These islands increase in size with particle energy and can seriously affect the confinement of high-energy ions.
Continuous flow
Authors: Alamry Abeer Yahia H. , Al-Antaki Ahmed Hussein Mohammed , Luo Xuan , Raston Colin L.
Published: May 2022

Nanospheres comprised of bovine serum albumin (BSA) crosslinked with glutaraldehyde possessing different pore sizes are accessible under continuous flow conditions using a vortex fluidic device (VFD) with a rapidly rotating tube tilt angle θ of −45° which overcomes an otherwise build-up of material occurring at θ +45°. The build-up can also be overcome at +45° under continuous flow using ethanol dehydrating conditions at 80°C without the need for crosslinking using glutaraldehyde. As-prepared BSA nanoparticles (BNPs) of ca. 531 nm in diameter were formed at 5k rpm in a single-step process. Similar rapid processing in the presence of curcumin affords composite BNPs@curcumin particles ca. 615 nm in diameter.
Can ash from smoldering fires increase peatland soil pH?
Authors: Marcotte A. L. , Limpens J. , Stoof C. R. , Stoorvogel J. J.
Published: May 2022

Peatland wildfire frequency and severity are increasing globally owing to climate change. The direct risk of elevated greenhouse gas emissions from peat burning receives much attention, yet the risks to vegetation composition or peat decomposition from alkaline ash inputs are poorly understood. We explored whether ash produced during smoldering increases peatland topsoil (∼0–25 cm) pH through field observations and laboratory experiments. We assessed spatial patterns of smoldering and ash presence, and measured soil and ash pH after a peatland wildfire in the Netherlands. Additionally, a peat smoldering experiment was conducted to compare freshly produced ash pH with aged ash pH collected 2 months following the wildfire. Additionally, we assessed the amount of ash needed to increase soil pH. Results showed that ash inputs at the field site were insufficient to increase pH of the acidic peatland after the wildfire. Incubation experiments showed that a ≥3 cm ash layer (ash load 163 t ha–1) would be required to increase soil pH by at least 1 unit. Given that aged ash was slightly acidic and fresh ash was alkaline, leaching and neutralisation of ash after wildfire is likely, suggesting that elevated soil pH from ash input may be transient rather than long term.
Ancient proteins resolve controversy over the identity ofGenyorniseggshell
Authors: Demarchi Beatrice , Stiller Josefin , Grealy Alicia , Mackie Meaghan , Deng Yuan , Gilbert Tom , Clarke Julia , Legendre Lucas J. , Boano Rosa , Sicheritz-Pontén Thomas , Magee John , Zhang Guojie , Bunce Michael , Collins Matthew James , Miller Gifford
Published: May 2022

The realization that ancient biomolecules are preserved in “fossil” samples has revolutionized archaeological science. Protein sequences survive longer than DNA, but their phylogenetic resolution is inferior; therefore, careful assessment of the research questions is required. Here, we show the potential of ancient proteins preserved in Pleistocene eggshell in addressing a longstanding controversy in human and animal evolution: the identity of the extinct bird that laid large eggs which were exploited by Australia’s indigenous people. The eggs had been originally attributed to the iconic extinct flightless birdGenyornis newtoni(†Dromornithidae, Galloanseres) and were subsequently dated to before 50 ± 5 ka by Miller et al. [Nat. Commun.7, 10496 (2016)]. This was taken to represent the likely extinction date for this endemic megafaunal species and thus implied a role of humans in its demise. A contrasting hypothesis, according to which the eggs were laid by a large mound-builder megapode (Megapodiidae, Galliformes), would therefore acquit humans of their responsibility in the extinction ofGenyornis. Ancient protein sequences were reconstructed and used to assess the evolutionary proximity of the undetermined eggshell to extant birds, rejecting the megapode hypothesis. Authentic ancient DNA could not be confirmed from these highly degraded samples, but morphometric data also support the attribution of the eggshell toGenyornis. When used in triangulation to address well-defined hypotheses, paleoproteomics is a powerful tool for reconstructing the evolutionary history in ancient samples. In addition to the clarification of phylogenetic placement, these data provide a more nuanced understanding of the modes of interactions between humans and their environment.
Non-coherent cohesive texts
Authors: Abu-Ayyash Emad A. S.
Published: May 2022

This article examines the function of cohesive devices (i.e., the linguistic tools that are usually used to link the various parts of the text) in Beckett’sWaiting for Godot. In Lucky’s soliloquy, certain cohesive devices are employed intensively so as to impede immediate understanding. At the same time, Beckett’s distinctive use of cohesive devices uniquely establishes a more profound awareness of the work’s message, which this article identifies as strategic coherence. This paper employed an embedded (QUAL:quan) mixed-methods approach and a validated model of cohesion to analyse Lucky’s speech.
A cartography of translation
Authors: Hofeneder Philipp
Published: May 2022

Space as an epistemological category has a long history within the humanities in general and has attracted increasing attention more recently in translation studies. It has come to be understood predominantly as a discursive category (e.g., cultural spaces in a figurative sense) and the product of social interactions (cf. the relationship between agents). This contribution focuses for the first time on the physical movement within an eminent translatorial project at the beginning of the 19th century in Russia. Where do these translators come from, where do they move to and where do they leave after finishing the translation? In addressing those questions, this case study brings to the fore the relevant spatial relations of translators, translations and other agents engaged in a translation. Several thematic maps are produced, which are helpful for visualizing these movements in space and for situating a translation space in the context of its physical surroundings.
Determination of the solution of a stochastic parabolic equation by the terminal value
Authors: Dou Fangfang , Du Wanli
Published: May 2022

This paper studies the inverse problem of determination the history for a stochastic diffusion process, by means of the value at the final time T. By establishing a new Carleman estimate, the conditional stability of the problem is proven. Based on the idea of Tikhonov method, a regularized solution is proposed. The analysis of the existence and uniqueness of the regularized solution, and proof for error estimate under an a priori assumption are present. Numerical verification of the regularization, including numerical algorithm and examples are also illustrated.
Effect of spin–orbit interaction on circular current: pure spin current phenomena within a ring conductor
Authors: Patra Moumita
Published: May 2022

A net circulating current may appear within a quantum ring under finite bias. We study the characteristic features of the circular current in the presence of Rashba spin–orbit interaction (RSOI). Both charge and spin currents appear within the ring. Whereas when the ring is symmetrically connected to the external leads, we can get a pure spin current at non-zero Fermi-energy. On the other hand, for asymmetric ring-to-leads configuration, at zero Fermi-energy, the spin current vanishes but a pure charge current flows within the ring. Tuning RSOI, we demonstrate a way to control the pure spin current externally. This new perspective of the generation of the pure spin circular current can open a new basis for the highly efficient, low energy cost spintronic devices.
Development and prospect of the nodal cable-free seismograph: a review
Authors: Lv Shixue , Lin Jun , Yang Hongyuan , Tian Ruyun , Wang Longxu , Bin Kangcheng , Tong Xunqian , Li Ang
Published: May 2022

The performance of seismic exploration instruments directly affects the quality of acquired seismic data as well as the efficiency of seismic survey operation. Consequently, they play a pivotal role in oil/gas and mineral resource exploration. Compared with traditional cabled seismic acquisition systems, nodal seismic acquisition systems have the advantages of light weight, small size, low capital and operational cost, reduced health safety and environment risk and strong adaptability to complex terrain environment. Therefore, they have been widely used in seismic exploration and have shown a trend of accelerated development. The major manufacturers have carried out research and development of nodal instruments, and various types of nodal seismographs have appeared. Based on the investigation of influential nodal seismographs, we summarize the research status of nodal seismographs. Based on different wireless monitoring capabilities and data harvesting modes, we classify the nodal seismographs into a shoot-blind system, semi-blind system, real-time system and enhanced real-time system. We discuss structural principles and key technologies of the four types of nodal seismographs, analyze their characteristics and predict their future development directions. Focusing on node data quality monitoring, we discuss the application of communication technologies, such as Bluetooth, Wi-Fi, ZigBee, Long Term Evolution, and satellites in nodal seismographs in detail. Furthermore, we analyze and evaluate three main networking architectures including planar multi-hop networks, hierarchical cluster networks and hybrid networks, and sum up the research progress of wireless routing algorithms and large-scale seismic data real-time harvesting methods. Finally, the latest applications of nodal seismographs in energy and mineral resource exploration, geological environment monitoring, urban subsurface space survey and novel seismic technologies are covered. As research on the application of micro-electro-mechanical systems technology, cloud computing, 5G, Internet of Things, edge computing, machine learning and robotics in nodal systems deepens, the performance of nodal seismographs will be greatly promoted.
Quantum transport in CVD graphene synthesized with liquid carbon precursor
Authors: Yi Xin , Song Qiyang , Chen Qiao , Zhao Chuanwen , Watanabe Kenji , Taniguchi Takashi , Chen Qiao , Yan Chengyu , Wang Shun
Published: May 2022

Large-area high-quality graphene enabled by chemical vapor deposition (CVD) can possibly pave the path for advanced flexible electronics and spintronics. CVD-grown method utilizing liquid carbon precursor has recently been demonstrated as an appealing choice for mass graphene production, thanks to its low cost and safe operation. However, the quality of the graphene film has been the major obstacle for the implementation of the liquid-precursor-based CVD method. Here we report the growth of centimeter-scale easily-transferable single-layer graphene (SLG) using acetone as a liquid carbon precursor. The dry-transfer technique was used to prepare the graphene device. The typical mobility of the dry-transferred SLG device is as high as 12 500 cm2 V−1 s−1 at room temperature. Thanks to the high quality of the device, the robust quantum Hall effect can survive up to room temperature. The excellent device quality also enables us to observe the Shubnikov–de Haas oscillation in the low magnetic field regime and systemically study the leading scattering mechanism. We extracted both the transport scattering time τ
t and the quantum scattering time τ

q
over a wide range of carrier density. The ratio of the scattering times suggests that the charged-impurity resided near the surface of the graphene restricted the device performance.
Two-step aberration correction: application to transcranial histotripsy
Authors: Lu Ning , Hall Timothy L , Sukovich Jonathan R , Choi Sang Won , Snell John , McDannold Nathan , Xu Zhen
Published: May 2022

Objective: Phase aberration correction is essential in transcranial histotripsy to compensate for focal distortion caused by the heterogeneity of the intact skull bone. This paper improves the 2-step aberration correction (AC) method that has been previously presented and develops an AC workflow that fits in the clinical environment, in which the computed tomography (CT)-based analytical approach was first implemented, followed by a cavitation-based approach using the shockwaves from the acoustic cavitation emission (ACE). Approach: A 700 kHz, 360-element hemispherical transducer array capable of transmit-and-receive on all channels was used to transcranially generate histotripsy-induced cavitation and acquire ACE shockwaves. For CT-AC, two ray-tracing models were investigated: a forward ray-tracing model (transducer-to-focus) in the open-source software Kranion, and an in-house backward ray-tracing model (focus-to-transducer) accounting for refraction and the sound speed variation in skulls. Co-registration was achieved by aligning the skull CT data to the skull surface map reconstructed using the acoustic pulse-echo method. For ACE-AC, the ACE signals from the collapses of generated bubbles were aligned by cross-correlation to estimate the corresponding time delays. Main results: The performance of the 2-step method was tested with 3 excised human calvariums placed at 2 different locations in the transducer array. Results showed that the 2-step AC achieved 90 ± 7% peak focal pressure compared to the gold standard hydrophone correction. It also reduced the focal shift from 0.84 to 0.30 mm and the focal volume from 10.6 to 2.0 mm3 on average compared to the no AC cases. Significance: The 2-step AC yielded better refocusing compared to either CT-AC or ACE-AC alone and can be implemented in real-time for transcranial histotripsy brain therapy.
Miniaturized FPI-FBG integrated sensor for parallel monitoring of magnetic field and magnetic fluid refractive index
Authors: Samavati Zahra , Samavati Alireza , Ismail Ahmad Fauzi , Othman Mohd Hafiz Dzarfan
Published: May 2022

In this paper, a sensor combining Fabry–Perot interferometer (FPI) with fiber Bragg grating (FBG) is designed, fabricated, and experimentally demonstrated as an excellent alternative to traditional sensors to detect the magnetic field and refractive index (RI), simultaneously. The sensor comprises a magnetostrictive Ni-Fe alloy coated on partially-unclad FBG, connecting the two reflecting surfaces of the micro-FPI cavity. The magnetostrictive analysis shows that magnetostriction reaches the maximum value at 59.3% Ni concentration. The sensor performance test was conducted on the RI of magnetic fluid and external magnetic field changes. The probe sensitivity was found to be as high as 625.38 nm/RIU and 7.71 nm mT−1, respectively. A matrix for simultaneous measurement of the magnetic field and RI was constructed using these sensitivity values. The stability of the sensor system over more than 300 h is at a satisfactory level. Considering the accurate FBG modulation and particular design of the experiment proposed by this method, the resolution of 1.69 × 10−4 RIU and 0.016 mT for magnetic fluid and magnetic field could be achieved, respectively, which can meet the sensing demand for a wide range of applications.
How to optimally combine pre-reconstruction full shape and post-reconstruction BAO signals
Authors: Gil-Marín Héctor
Published: May 2022

We review the different approaches for combining the cosmological information from the full shape of the pre-reconstructed power spectrum — usually referred as redshift-space distortion (RSD) analysis — and from the baryon acoustic oscillation (BAO) peak position in the post-reconstructed power spectrum with the aim of finding the optimal procedure. We focus on combining the pre- and post-reconstructed derived quantities at different compression levels: 1) the two-point summary statistics, the power spectrum multipoles, P(ℓ)(k); 2) the compressed BAO variables,α∥,⊥; and 3) an hybrid approach between 1) and 2). We apply these methods to the publicly available eBOSS Luminous Red Galaxy catalogues, for both data and synthetic EZ-mocks. We find that the three approaches result in very consistent posteriors when the appropriate covariance matrix estimator is used. On average, the combination at P(ℓ)(k) level retrieves 5-10% tighter constraints than the other two approaches, demonstrating that the standard approach of combining at the level of the BAO variables is nearly optimal. We conclude that combining both BAO post-reconstructed and full shape pre-reconstructed signals for the one single data realization at the level of the summary statistics is faster, as it does not require running the whole pipeline on the individual mocks, and brings a moderate 10% improvement, with respect to the other two studied methods. Moreover, we check for potential systematics, such as, the way the matrix is built and the effect of the finite number of mocks on the likelihood estimator and find none of these have a significant impact in the final results. Combining the pre- and post-reconstruction signals at the level of the summary statistics is an attractive, faster and accurate method to be used in future and on-going spectroscopic surveys.