bluuebunny/crossref_metadata_2025 huggingface dataset:
Online restricted access molecularly imprinted solid-phase extraction coupled with liquid chromatography-mass spectrometry for the selective determination of serum bile acids
Authors: Silveira Alberto Thalison , Barbosa Alyne Maria da Costa , de Faria Henrique Dipe , Marciano Luiz Paulo de Aguiar , Figueiredo Eduardo Costa , Martins Isarita
Published: May 2022

Synthesis of a RAM imprinted polymer covered with bovine serum albumin applied to determine bile acids from individuals exposed to organic solvents using an online-LC method.
Trihexyltetradecylphosphonium chloride based ratiometric fluorescent nanosensors for multiplex anion discrimination
Authors: Liu Yueling , Fan Jianhua , Zhang Ni , Xu Huiying , Su Wei , Qin Yu , Jiang Dechen
Published: May 2022

A multiplex anion-responsive platform was developed with [THTP][Cl] and ETH5350, providing colorimetric and spectroscopic transformations. By choosing suitable ionophores, a pool of nanosensors for extended anions could be achieved.
Spontaneous, co-translational peptide macrocyclization using p-cyanoacetylene–phenylalanine
Authors: Franco H. Estheban Osorio , Chaloux Brennan T. , Hartman Matthew C. T.
Published: May 2022

A chemoselective, spontaneous, and versatile cyclization chemistry is developed for peptide macrocyclization during in vitro translation. Stable peptides in a wide variety of ring sizes including doubly-cyclized structures can be made in high yield.
Native ambient mass spectrometry of intact protein assemblies directly fromEscherichia colicolonies
Authors: Du Yuying , May Robin C. , Cooper Helen J.
Published: May 2022

Electroporation combined with native liquid extraction surface analysis mass spectrometry allows analysis of intact protein assemblies directly from bacterial colonies.
Diverse reactivity of an Al(i)-centred anion towards ketones
Authors: Liu Han-Ying , Hill Michael S. , Mahon Mary F.
Published: May 2022

An alumanyl anion provides significant diversity of outcome in reactions with ketone small molecules, from C–C coupling to C–H activation.
Sensitive luminescence mechanochromism and unique luminescence thermochromism tuned by bending the P–O–P skeleton in the diphosphonium/iodocuprate(i) hybrid
Authors: Yang Zhen-Cong , Song Kai-Yue , Zhou Pan-Ke , Zong Lu-Lu , Li Hao-Hong , Chen Zhi-Rong , Jiang Rong
Published: May 2022

The unique luminescence mechano/thermochromism of a diphosphonium/iodocuprate(i) hybrid is led by the mechanically induced adjustments in cuprophilic interactions and bent P–O–P backbone upon heating.
The effect of substituents and their positions on a series of disubstituted naphthalene bromide salts towards intermolecular interactions and crystal packing
Authors: Yeoh Wei-Jiun , Sobolev Alexandre N. , Paterson Martin J. , Dalgarno Scott J. , Ling Irene
Published: May 2022

Naphthalene derived dications bearing different N-heterocyclic substituents appended at different positions demonstrated conformational flexibility and interesting self-assembled packing motifs when crystallised in the solid state as bromide salts.
rGO functionalized (Ni,Fe)-OH for an efficient trifunctional catalyst in low-cost hydrogen generation via urea decomposition as a proxy anodic reaction
Authors: Shrestha Nabeen K. , Patil Supriya A. , Inamdar Akbar I. , Park Sunjung , Yeon Seungun , Shin Giho , Cho Sangeun , Kim Hyungsang , Im Hyunsik
Published: May 2022

A simple and scalable immersion-based corrosion induced strategy to integrate rGO nanosheets and Ni–Fe-based hydroxide nanocatalysts on nickel foam at 25 °C, demonstrating an efficient electrocatalysis for low-cost hydrogen generation.
On the role of citrate in 12-molybdophosphoric-acid methods for quantification of phosphate in the presence of ATP
Authors: Recoulat Angelini Alvaro A. , Martínez Gache Santiago A. , Sabeckis M. Lurdes , Melian Noelia A. , González Flecha F. Luis
Published: May 2022

Citrate is a useful additive for measuring ATPase activities avoiding the interference of phosphate release after catalysis. In this work we explore this effect, and optimize the malachite green procedure for determination of phosphate.
Gold-catalyzed cycloadditions of allenesviametal carbenes
Authors: Gao Guang-Qin , Ma Guang , Jiang Xiao-Lei , Liu Qing , Fan Cai-Ling , Lv Dong-Can , Su Hui , Ru Guang-Xin , Shen Wen-Bo
Published: May 2022

This review will focus on gold-catalyzed cycloadditions of allenes as efficient methods of assembling functionalized cyclic moleculesviagold carbenes.
Systematic KMTNet planetary anomaly search
Authors: Gould Andrew , Han Cheongho , Zang Weicheng , Yang Hongjing , Hwang Kyu-Ha , Udalski Andrzej , Bond Ian A. , Albrow Michael D. , Chung Sun-Ju , Jung Youn Kil , Ryu Yoon-Hyun , Shin In-Gu , Shvartzvald Yossi , Yee Jennifer C. , Cha Sang-Mok , Kim Dong-Jin , Kim Hyoun-Woo , Kim Seung-Lee , Lee Chung-Uk , Lee Dong-Joo , Lee Yongseok , Park Byeong-Gon , Pogge Richard W. ,   (The KMTNet Collaboration), Mróz Przemek , Szymański Michał K. , Skowron Jan , Poleski Radek , Soszyński Igor , Pietrukowicz Paweł , Kozłowski Szymon , Ulaczyk Krzysztof , Rybicki Krzysztof A. , Iwanek Patryk , Wrona Marcin ,   (The OGLE Collaboration), Abe Fumio , Barry Richard , Bennett David P. , Bhattacharya Aparna , Fujii Hirosame , Fukui Akihiko , Hirao Yuki , Silva Stela Ishitani , Kirikawa Rintaro , Kondo Iona , Koshimoto Naoki , Matsubara Yutaka , Matsumoto Sho , Miyazaki Shota , Muraki Yasushi , Okamura Arisa , Olmschenk Greg , Ranc Clément , Rattenbury Nicholas J. , Satoh Yuki , Sumi Takahiro , Suzuki Daisuke , Toda Taiga , Tristram Paul J. , Vandorou Aikaterini , Yama Hibiki ,   (The MOA Collaboration), Beichman Charles , Bryden Geoffry , Novati Sebastiano Calchi , Gaudi B. Scott , Henderson Calen B. , Penny Matthew T. , Jacklin Savannah , Stassun Keivan G. ,   (The UKIRT Microlensing Team)
Published: May 2022

We complete the analysis of all 2018 prime-field microlensing planets identified by the Korea Microlensing Telescope Network (KMTNet) Anomaly Finder. Among the ten previously unpublished events with clear planetary solutions, eight are either unambiguously planetary or are very likely to be planetary in nature: OGLE-2018-BLG-1126, KMT-2018-BLG-2004, OGLE-2018-BLG-1647, OGLE-2018-BLG-1367, OGLE-2018-BLG-1544, OGLE-2018-BLG-0932, OGLE-2018-BLG-1212, and KMT-2018-BLG-2718. Combined with the four previously published new Anomaly Finder events and 12 previously published (or in preparation) planets that were discovered by eye, this makes a total of 24 2018 prime-field planets discovered or recovered by Anomaly Finder. Together with a paper in preparation on 2018 subprime planets, this work lays the basis for the first statistical analysis of the planet mass-ratio function based on planets identified in KMTNet data. By systematically applying the heuristic analysis to each event, we identified the small modification in their formalism that is needed to unify the so-called close-wide and inner-outer degeneracies.
High order sliding mode control of active and reactive powers for DFIG based Wind turbine
Authors: El qouarti Ouassima , Essadki Ahmed , Nasser Tamou
Published: May 2022

Grid connected wind turbines are considered as a wise alternative to conventional energy sources; not only they are used to produce energy, but they have been recently operated in order to provide grid ancillary services such as stability and frequency control. In this paper we are going to deal with the famous doubly fed induction generator (DFIG) based Wind Energy Conversion Systems (WECS) for its variable speed operation and excellent power quality. The purpose of this study is to apply a High Order Sliding Mode Control (HOSMC) based on vector control and to compare the results with the first order sliding mode control (FOSMC) in order to evaluate the performances of stability and chattering elimination under normal conditions. Simulation results show the superiority of the SOSMC over the FOSMC in terms of robustness and chattering elimination.
Security issues of the Web of Things: challenges and solutions
Authors: Laaychi Abdelaziz , Tanana Mariam , Lazaar Saiida
Published: May 2022

Our world is hugely impacted by revolutionary innovations in telecommunication technologies where connected objects increase rapidly. The Web of Things (WoT) represents the most promising application models of the Internet of Things (IoT). The ultimate goal of the WoT is to create a search engine where the user or devices can find other devices anywhere and anytime in order to take advantage of the resources of other devices. Nowaday, IoT systems imperatively need scalability and flexible coupling, which are easily offered by WoT. However, researchers have raised some concerns about the security of WoT. This paper provides a recent review of WoT literature. A special attention is accorded to the most relevant WoT security issues. Our paper also deals with the most important attacks in the domain and with some selected security solutions.
ESPRIT-TLS and ANN Genetic Algorithm combination for an accurate discrimination of fault bearing in induction machines
Authors: Dore Pascal , Chakkor Saad , El Oualkadi Ahmed
Published: May 2022

Fault detection is a strategy that can be easily implemented. Indeed, electrical rotating machines have played and still play an important role in many applications where very often continuity of operation is crucial (aircraft, ships, electric vehicles, industries, etc.). In the case of electromechanical systems, several failures can occur and especially in inaccessible locations (bearing faults, rotor bar breakage, misalignment, eccentricity, cracks, or gear breakage).To ensure acceptable levels of reliability and safety, effective diagnostic methods (at the earliest stage of fault occurrence), fault monitoring, and fault handling are mandatory to avoid any production downtime or loss and to reduce additional repair costs. The detection of these faults by MCSA (Motor Current Signature Analysis) and Principal Component Analysis (PCA) has been widely explored and applied. These techniques are mainly based on the analysis of the stator current by advanced signal processing algorithms to extract useful information for the detection and characterization of defects and their accurate classification. The remarkable limitations of these approaches have prompted researchers to improve their accuracy and to enhance their complexity. In this work, we propose by study the application of ANN-GA (Artificial Neural Networks - Genetic Algorithm) combined with ESPRIT method variants for efficient faults recognizing in real-time. Computer simulations in MATLAB demonstrated that ESPRIT TLS (Estimation of Signal Parameters via Rotational Invariant Techniques Total Least Square) variant allows satisfactory precision in discriminating bearing fault even with a noisy signal. Moreover, this algorithm is suitable for application in dataset preparation and in ANN training for the development of a classification model. According to study finding, Genetic Algorithm optimize ANN architecture for identifying each fault type with very good accuracy in time or frequency domains.
Overview of Non-Intrusive Load Monitoring: Probabilistic and Artificial Intelligence approaches
Authors: Ouzine Jamila , Marzouq Manal , Bennani Saad Dosse , Lahreche Khadija , El Fadili Hakim
Published: May 2022

Reduction and conservation of electrical energy consumption in residential buildings is the main objective of Non-Intrusive Load Monitoring (NILM) techniques. NILM detects events and estimate the power consumption of individual appliances by analyzing the aggregate power consumption measured at the service entry. Indeed, our major contribution in this paper is to update research works on NILM methodologies by adding the most recent NILM methods proposed in the literature. In this paper we present an overview of NILM and energy disaggregation methods. Then, we discuss the challenges of this technique to provide useful recommendations for future research.
A Deep Learning Model for Coronavirus 2019 Pneumonia Screening
Authors: Oubaha Rachid , Hlali Azzeddine , El ouaazizi Aziza
Published: May 2022

This paper proposes an automatic COVID-19 detection model using chest X-ray images. The proposed model is developed to give accurate diagnostics for multiclass classification (COVID vs. PNEUMONIA vs. NORMAL). Our model produced a classification accuracy of 96%. Evaluation has been done on publicly available databases containing covid19, pneumonia and normal X-ray images. The proposed approach uses the VGG-16 model with pre-trained weights in the initialization step.
Optimal Interdigitated Electrode Sensor Design for biosensors using Differential Evolution Algorithm
Authors: Sabiri Issa , Bouyghf Hamid , Raihani Abdelhadi
Published: May 2022

Optimization of interdigitated electrode sensor design is essential for practical impedance spectroscopy in the medical and pharmaceutical fields because of their easy fabrication procedure and inexpensive. The geometry presents a prospective for ameliorating sensitivity over other microelectrode designs. The geometric optimization of a sensor’s structure with interdigital electrodes is one of the difficult optimization problems. To solve this type of problem, we use metaheuristic methods to find the optimal solution. The method chosen in this paper is the differential evolution algorithm DE, which is widely used to solve the overall optimization problem. We will optimize the geometrical parameters of the interdigitated electrodes by minimizing the FLow, the proper band [FLow<-->FHigh] using MATLAB script, the validity of the obtained results is investigated using ADS tools
Ultrasonic signal noise reduction based on convolutional autoencoders for NDT applications
Authors: Mansouri Nabil Jai , Khaissidi Ghizlane , Despaux Gilles , Mrabti Mostafa , Le Clézio Emmanuel
Published: May 2022

One of the most challenging problems of ultrasonic non-destructive testing is the signal distortion caused by the presence of noise, yielding the sound wave corruption and thus degrading the ultrasonic imaging technology performance due to Time of flight methods’ loss of precision. Deep learning algorithms have proven their effectiveness in reducing noise on several types of signals in different domains. In this paper, we propose a one-dimensional convolutional autoencoder for ultrasonic signal denoising. The efficiency of the proposed architecture is compared to the wavelet decomposition method, collating the peak signal-to-noise ratio values on the denoised signals. Our method proved its potential for NDT applications in recovering temporal information even on very noisy signals, and improving the PSNR by about 30 dB.
Frequency Control and Energy Management of Microgrid with Distributed Energy Storage
Authors: Chekira Ouadiâ , Boharb Ali , Lamhamdi Tijani , El Moussaoui Hassan , El Markhi Hassane , Amine Beniss Mohamed
Published: May 2022

The purpose of the Energy Management System (EMS) is to ensure a high degree of efficiency, stability, and dependability. And the electrical system should have the ability to adjust to the majority of changes such as renewable energy integration. In some situations, the power generated by distributed power sources is greater than the local demand. This has an effect on the microgrid's stability and frequency. Smart energy management in a microgrid is proposed in this research., consisting of a wind power generator, photovoltaic and storage energy system for frequency regulation, and system balance. The above paper's main contribution is a system for managing energy. based on a clever strategy using MATLAB/Simulink. The results of the simulation and analyses demonstrate that the suggested microgrid energy management system is efficient at balancing energy.
Selection of suitable concentrated solar power farm’s locations A Case study: Fez-Meknes Region, Morocco
Authors: Ali Abdelkhiar Ait , Chahidi Laila Ouazzani , Mechaqrane Abdellah , Charroud Mohammed , Ouahzizi Youssef , Choukrad Jaouad
Published: May 2022

Nowadays, the transition to green energies becomes a necessity in the worldwide. In order to have an optimal yield, the selection of the adequate site for a given technology is required. In this study, the geographical environment of Fez-Meknes region, Morocco, is explored to select suitable location for concentrated solar power plants (CSP). For this purpose, a combination of a geographic information system (GIS) and the multi-criterion decision-making (MCDM) method is used for this aim. Various factors are taken into consideration, namely climate conditions, environment, water resources and location. These criteria are calculated and weighted using the Analytical Hierarchy Process (AHP) approach. The findings indicate that the Fez-Meknes region is a viable location for the implementation of CSP plants. Thus, the most suitable site represents 12% of the total region area. These suitable areas are located in the southern and southeastern part of the region with an irradiation value of about 6.57 kWh/m2/yr.
Optimization of packet forwarding scheduling in wireless ad-hoc networks: Deployment on a 3D environment
Authors: Boukrim Mustapha , Antari Jilali
Published: May 2022

The key aim of a multi-hop wireless network is to increase service efficiency in terms of transmission scheduling, packet transfer volume, and other factors. In a practical deployment of Ad- Hoc wireless network in three-dimensional (3D) environments, we study the optimizing transmission scheduling problem by end-to-end latency minimization using the signal-to-interference-and-noise rate (SINR) mechanism. Two strategies are considered. The former directly deals with end-to-end latency and eliminates the constraint of frame periodicity. The latter combines two cooperative transmission and transmission interference suppression models. The properties of both strategies are analyzed, and mixed-integer programming (MIP) models and solution heuristics are developed. Simulation results are presented to clarify the end-to-end latency performance of strategies, especially in 3D environments.
A new design of 5G planar antenna with enhancement of the bandwidth and the gain using metasurface
Authors: Bellekhiri Abderrahim , Chahboun Noha , Laaziz Yassin , El Oualkadi Ahmed
Published: May 2022

This work presents and describes the design of a novel multilayer antenna structure based on metasurfaces for 5G mobile applications. The suggested antenna has good matching input impedance around 28 GHz, a bandwidth of 2.2 GHz, and an enhancement of gain in comparison with standard patch antenna. This antenna is mounted on two substrates; the first one is the foam, and the second is Roger’s substrate suitable for 5G mobile applications. The whole dimensions of the final circuit are 3.28x4.23mm2. The proposed antenna structure has a high gain, good matching of input impedance and an aperture angle of 57 ° which is more directive compared to the rectangular antenna element.
High-frequency Si/SiGe phototransistor model: Operation on multiple polarization points
Authors: Diop A.M. , Bennour A. , Mazer S , El Bekkali M. , Fattah M. , Polleux J-L. , Algani C.
Published: May 2022

This article presents the results of our research on the modeling of an HPT SiGe heterojunction phototransistor. Usually this HPTs type work for a single point of polarization in this work, we were interested in modeling the same HPT on different points of polarization. We will model the HPT to operate at both 2V and 3V, so that we can use the HPT at multiple bias points and reduce costs and allow the reuse of the HPT SiG heterojunction phototransistor on further studies. For a defined point of polarization we will optimize the operation of the HPT so that it flies with the dynamic measurements and we will not base on this HPT by modifying certain values and components so that the HTP works on the other points of polarization.
Sign Language Recognition: High Performance Deep Learning Approach Applyied To Multiple Sign Languages
Authors: El Zaar Abdellah , Benaya Nabil , El Allati Abderrahim
Published: May 2022

In this paper we present a high performance Deep Learning architecture based on Convolutional Neural Network (CNN). The proposed architecture is effective as it is capable of recognizing and analyzing with high accuracy different Sign language datasets. The sign language recognition is one of the most important tasks that will change the lives of deaf people by facilitating their daily life and their integration into society. Our approach was trained and tested on an American Sign Language (ASL) dataset, Irish Sign Alphabets (ISL) dataset and Arabic Sign Language Alphabet (ArASL) dataset and outperforms the state-of-the-art methods by providing a recognition rate of 99% for ASL and ISL, and 98% for ArASL.
Deep Learning for Epilepsy monitoring: A survey
Authors: Amrani Ghita , Adadi Amina , Berrada Mohammed , Souirti Zouhayr
Published: May 2022

Diagnosis of epilepsy can be expensive, time-consuming, and often inaccurate. The gold standard diagnostic monitoring is continuous video-electroencephalography (EEG), which ideally captures all epileptic events and dis-charges. Automated monitoring of seizures and epileptic activity from EEG would save time and resources, it is the focus of much EEG-based epilepsy research. The purpose of this paper is to provide a survey in order to understand, classify and benchmark the key parameters of deep learning-based approaches that were applied in the processing of EEG signals for epilepsy monitoring. This survey identifies the availability of data and the black-box nature of DL as the main challenges hindering the clinical acceptance of EEG analysis systems based on Deep Learning and suggests the use of Explainable Artificial Intelligence (XAI) and Transfer Learning to overcome these issues. It also underlines the need for more research to recognize the full potential of big data, Computing Edge, IoT to implement wearable devices that can assist epileptic patients and improve their quality of life.
Current state of local populations Tulipa greigii Regel (Liliaceae) in Uzbekistan
Authors: Abduraimov Ozodbek S. , Maxmudov Azizbek V. , Abduraimov Azizbek S.
Published: May 2022

Our research was carried out in the ridges of the Western Tien Shan (Uzbekistan). The study analyzed the age structure of 9 local populations (LP) of Tulipa greigii Regel. The ontogenetic structure of T. greigii local populations is represented by two types of spectrum – left-sided (LP 1, 2, 4, 5, 6, 8, 9) and centered (LP 3, 7). The studied local populations of T. greigii are normal, incomplete. It is noted that the studied local populations are young and mature. The scientific justification of the ways of ecological improvement of coenopopulation. In the implementation of scientific work, the methods of traditional geobotanical and cartographic remote study of plant formations were applied.
Model of System Microgrid in radial Topology using Euler-Lagrange Equation
Authors: Nahir Abir , Abelilah Jalid
Published: May 2022

The need of power and equipment that can serve to distribute the electric energy becomes primordial things this period that almost of domains’ specialists work in, and one of this equipment is microgrid system that gain more and more places in not just industrial area but almost domestic area, however, rural or urban. This equipment is can be worked in synchronization with the main grid or worked alone provides its own needs in alimentation and characteristics via the distributed generators. In fact, micro-grid is a complex system controlled and powerful in sense of distribution energy with minimum losses that have variety in specifics and also in the mode of working but haven’t a specific model that presents its function correctly. So, our study is interested in the analytical modeling of the micro-grid via the Euler Lagrange equations. After using the (ELE) method as tools to model the micro-grid, we simulate it through MATLAB/Simulink. The simulation result shows that the model presents the behavior of the micro-grid in mode isolated and connected in radial topology.
Pronostiquer tôt les troubles du spectre autistique : Un défi ?
Authors: Ben-Ari Yehezkel , Caly Hugues , Rabiei Hamed , Lemonnier Éric
Published: May 2022

Les troubles du spectre de l’autisme (TSA) « naissent » in utero à la suite d’évènements pathologiques génétiques ou environnementaux. Le diagnostic des TSA n’est cependant effectué que vers l’âge de 3-5 ans en Europe et aux États-Unis. Un pronostic précoce permettrait pourtant d’atténuer la sévérité des atteintes cognitives, grâce à des approches psycho-éducatives. Une large panoplie d’approches a été suggérée pour établir un pronostic précoce des TSA, se fondant sur l’imagerie cérébrale, sur des enregistrements EEG, sur des biomarqueurs sanguins ou sur l’analyse des contacts visuels. Nous avons développé une approche fondée sur l’analyse par machine learning des données biologiques et échographiques recueillies en routine, du début de la grossesse au lendemain de la naissance, dans les maternités françaises. Ce programme qui permet d’identifier la presque totalité des bébés neurotypiques et la moitié des bébés qui auront un diagnostic de TSA quelques années plus tard, permet aussi d’identifier les paramètres ayant un impact sur le pronostic. Si quelques-uns d’entre eux étaient attendus, d’autres n’ont aucun lien avec les TSA. L’étude sans a priori des données de maternité devrait ainsi permettre un pronostic des TSA dès la naissance, ainsi que de mieux comprendre la pathogenèse de ces syndromes et de les traiter plus tôt.
Ultrasonographic Evaluation of Peripheral Nerves: Technical Considerations
Authors: Greenfield Antje L. , Parrikh Mannan , Kanesa-Thasan Riti
Published: May 2022

Advances in ultrasonographic (US) technology featuring high-resolution transducers have revolutionized US over recent years as a modality increasingly used in the evaluation of musculoskeletal structures and peripheral nerves. A wide variety of nerve pathologies can be detected, such as neoplastic and tumorlike lesions, entrapment syndromes, posttraumatic injuries, and inflammatory conditions. US can serve as an imaging tool for guiding percutaneous treatments, such as injection therapies or hydrodissection, and assist with perioperative nerve marking and visualization of peripheral nerves in the operating room. This article describes the normal US appearance of peripheral nerves, US imaging techniques, common peripheral nerve pathologies, and interventional applications.
Immunity: A Step-by-Step Overview
Authors: Sharma S.R. , Sharma Bindu
Published: May 2022

The immune system is an intricate network of various types of cells and proteins that defends the body against infectious diseases. Once the body encounters a pathogenic microorganism, the immune system gets activated and creates a defence mechanism to defeat it and at the same time retains its memory. In future, if the body encounters the same pathogen, it recognises and destroys the pathogen quickly. The whole pathophysiological mechanism involved in this process of defending the body and keeping a record of every pathogen it has encountered, is briefly elucidated. The paper presents a concise description that captures essential nature of immunobiology such as different types of immunity, components of immune system, role of each component and how complement proteins make a functional bridge between two types of immune system. Classification of immunity depicting physiological functioning of its major components and blood cells linked to immune system originating in bone marrow is depicted in flowcharts.
Noise signal as input data in self-organized neural networks
Authors: Kagalovsky V. , Nemirovsky D. , Kravchenko S. V.
Published: May 2022

Self-organizing neural networks are used to analyze uncorrelated white noises of different distribution types (normal, triangular, and uniform). The artificially generated noises are analyzed by clustering the measured time signal sequence samples without its preprocessing. Using this approach, we analyze, for the first time, the current noise produced by a sliding “Wigner-crystal”-like structure in the insulating phase of a 2D electron system in silicon. The possibilities of using the method for analyzing and comparing experimental data obtained by observing various effects in solid-state physics and numerical data simulated using theoretical models are discussed.
Phase of quantum oscillation in Weyl semimetals
Authors: Mikitik G. P. , Sharlai Yu. V.
Published: May 2022

We consider the semiclassical quantization condition for the energy of an electron in a magnetic field in the case when the electron orbit lies on a Fermi-surface pocket surrounding the Weyl point of a topological semimetal and analyze the constant γ appearing in this condition. It is shown that this constant has the universal value, γ = 0, independent on the tilt of the Weyl spectrum. Since the constant γ for an extremal cross section of the Fermi surface determines the phase of quantum oscillations, this result explains why measurements of the phase permit one to find Weyl points in crystals even though the extremal cross section of the pocket does not pass through this point, and the appropriate Berry phase of the orbit differs from π.
Time jitter generation and injection algorithms for high-speed applications
Authors: Wu Tong , Song Kezhu , Zhao Hongwei
Published: May 2022

Time jitter is an important means for evaluating the performance of high-speed communication systems. Current high-speed digital designs require faster edge speeds and smaller effective data windows. Therefore, analysis of the root cause of jitter has become the key factor in determining the success or failure of a design. To analyze the jitter source of the whole link, the jitter is usually extracted and analyzed by software or hardware at the receivers. To verify the accuracy of jitter extraction at the receivers, many instrument manufacturing companies have developed oscilloscope software to inject jitter at the transmitters, but the core algorithms for jitter generation are commercially sensitive and the software cannot inject all types of jitter, particularly bounded uncorrelated jitter, into the pure signals. This paper proposes a software jitter modeling and injection algorithm that can be implemented in MATLAB and includes transmitter test signal modeling, jitter generation, and the injection of various types of jitter. Unlike other research and commercial software, the proposed algorithm enables the injection of various types of jitter, notably bounded uncorrelated jitter, into test signals. This algorithm is suitable for integration into real-time oscilloscopes for jitter generation and injection.
A ferromagnetic spin source grown by atomic layer deposition
Authors: Quinard B. , Godel F. , Galbiati M. , Zatko V. , Sander A. , Vecchiola A. , Collin S. , Bouzehouane K. , Petroff F. , Mattana R. , Martin M.-B. , Dlubak B. , Seneor P.
Published: May 2022

We report on the growth of a ferromagnetic cobalt electrode by atomic layer deposition (ALD) and demonstrate it as a functional spin source in complete magnetic tunnel junctions (MTJs). Using an in situ protocol, we integrate a reference tunnel barrier on top of the ALD cobalt spin source stabilizing its metallic nature and allowing further characterization. The cobalt layer, grown in mbar conditions with chemical precursors, is assessed to be metallic and ferromagnetic using both x-ray photoelectron spectroscopy and superconducting quantum interference device magnetometry measurements. Atomic force microscopy tapping and conductive tip mode analyses reveal a very flat film with low roughness (0.2 nm RMS) with a high homogeneity of surface conductivity matching the best reference samples grown by sputtering. We finally evaluate its behavior in full MTJ spin valves, using a reference spin analyzer to highlight that the ALD grown layer is, indeed, spin polarized and can act as a functional spintronics electrode. This result opens the perspective of exploiting the benefits of ALD (such as the wide area low-cost process, extreme conformality, layer by layer growth of heterostructures, area selectivity, etc.) for spintronics applications.
Unraveling the optical bandgap and local structural change during phase transition in In3SbTe2 material through UV–Vis–NIR and XPS studies
Authors: Pathak Anushmita , Pandey Shivendra Kumar
Published: May 2022

The unique property of fast and reversible switching between SET (crystalline, highly conductive) and RESET (amorphous, highly resistive) phases of phase change materials has led to its usage in non-volatile memory applications. The quest for new phase change materials with enhanced properties is of utmost importance for developing memory devices that meet the current demand for high speed, better data retention, and multi-bit storage capabilities. We report the systematic changes occurring in the optical bandgap (Eg) and structural disorder (B12) in In3SbTe2 (IST) phase change material during the transition from amorphous to crystalline phases employing UV–Vis–NIR spectroscopy. Eg in IST ranges from 0.998 (amorphous) to 0.449 eV (crystalline), revealing higher bandgap values compared to widely used Ge2Sb2Te5. An increment of 22.7% in the Tauc parameter (B12) slope, which governs the structural disorder, is also observed during the cubic transition in IST, revealing a more ordered nature of IST in the crystalline phase. Moreover, a rise in Urbach energy (EU) from 33.4 (amorphous) to 150.2 meV (crystalline) exhibits an increase in disorder at elevated temperatures owing to film defects. These findings are supported by the change in the atomic bonding upon crystallization, which is studied using X-ray Photoelectron Spectroscopy (XPS). Our XPS findings demonstrate that the amorphous phase of IST is composed of In2Te3, InSb, and InTe species with a peak area of ∼52.97%, ∼51.26%, and ∼39.83%, respectively. XPS spectra of annealed samples reveal the phases separation of IST alloy into crystalline InSb (∼60.89%) and InTe (∼64.69%) around 300 °C and then the formation of stable cubic In3SbTe2 (∼47.54%) at 400 °C. These experimental findings of the optical properties with structural changes would help distinguish the IST from the conventional phase change materials.
Diffusion of turbulence following both stable and unstable step stratification perturbations
Authors: Gallana L. , Abdunabiev S. , Golshan M. , Tordella D.
Published: May 2022

The evolution of a two-phase, air and unsaturated water vapor, time-decaying, shearless, and turbulent layer has been studied in the presence of both stable and unstable perturbations of the normal temperature lapse rate. The top interface between a warm vapor cloud and clear air in the absence of water droplets was considered as the reference dynamics. Direct, three-dimensional, and numerical simulations were performed within a 6 × 6-m-wide and 12-m-high domain, which was hypothesized to be located close to an interface between the warm cloud and clear air. The Taylor microscale Reynolds number was 250 inside the cloud portion. The squared Froude's number varied over intervals of [0.4; 981.6] and [−4.0; −19.6]. A sufficiently intense stratification was observed to change the mixing dynamics. The formation of a sublayer inside the shearless layer was observed. The sublayer, under a stable thermal stratification condition, behaved like a pit of kinetic energy. However, it was observed that kinetic energy transient growth took place under unstable conditions, which led to the formation of an energy peak just below the center of the shearless layer. The scaling law of the energy time-variation inside the interface region was quantified: this is an algebraic law with an exponent that depends on the perturbation stratification intensity. The presence of an unstable stratification increased the differences in statistical behavior among the longitudinal velocity derivatives, compared with the unstratified case. Since the mixing process is suppressed in stable cases, small-scale anisotropy is also suppressed.
2D electronic-vibrational spectroscopy with classical trajectories
Authors: Polley Kritanjan , Loring Roger F.
Published: May 2022

Two-dimensional electronic-vibrational (2DEV) spectra have the capacity to probe electron–nuclear interactions in molecules by measuring correlations between initial electronic excitations and vibrational transitions at a later time. The trajectory-based semiclassical optimized mean trajectory approach is applied to compute 2DEV spectra for a system with excitonically coupled electronic excited states vibronically coupled to a chromophore vibration. The chromophore mode is in turn coupled to a bath, inducing redistribution of vibrational populations. The lineshapes and delay-time dynamics of the resulting spectra compare well with benchmark calculations, both at the level of the observable and with respect to contributions from distinct spectroscopic processes.
Non-invasive and non-destructive characterization of MBE-grown CdZnTe/CdTe superlattice-based dislocation filtering layers
Authors: Pan Wenwu , Nath Shimul Kanti , Ma Shuo , Gu Renjie , Zhang Zekai , Fu Lan , Faraone Lorenzo , Lei Wen
Published: May 2022

We report on the structural and optical properties of heteroepitaxial II–VI CdTe (211)B buffer layers with strained CdZnTe/CdTe superlattice layers, investigated by employing non-destructive methods including high-resolution x-ray diffraction, cathodoluminescence, and photoluminescence spectroscopy. X-ray diffraction reciprocal space mapping measurements revealed that the superlattice layers are coherently strained, leading to a spread in x-ray double-crystal rocking curve full-width at half-maximum values but better in-plane lattice-matching with HgCdTe. Both cross-sectional cathodoluminescence and photoluminescence measurements confirm the coherent growth of superlattice layers and their dislocation filtering effects. Both these techniques in CdTe layers are found to be well correlated with the dislocation density as determined by etch pit density measurements. The results indicate the potential of these non-destructive methods to be further developed into general-purpose techniques capable of characterizing the defect evolution in semiconductor heteroepitaxy.
Conservative compressible one-dimensional turbulence formulation and application to high-Reynolds-number compressible turbulent channel flows
Authors: Chen Chongpei , Liang Jianhan , Gao Tianyun , Wu Xiaoshuai , Zhao Wandong , Zhang Lin
Published: May 2022

One-dimensional turbulence (ODT) is an efficient stochastic methodology for turbulent flow simulation with dimensionality reduction. In this study, the conservative compressible ODT model is further developed and applied to address the challenge of accurately and economically modeling high-Reynolds-number wall-bounded compressible turbulent flows. The prohibitively costly direct numerical simulation (DNS) of multiscale motions for fully developed compressible turbulent channel flows is replaced by a much more economical simulation using the conservative compressible ODT model. The quantitative accuracy in capturing the main turbulent features, including the first-order mean statistics and the second-order and third-order turbulent fluctuation statistics, is verified by comparing the ODT results with different canonical DNS results at Mab = 0.5, 1.5, and 3.0. With its accuracy tested, the proposed ODT model is employed to capture the turbulent features of fully developed channel flows at Reynolds numbers widely ranging from 6000 to 60 000. The proposed ODT model reproduces Reynolds number effects in turbulent fluctuation statistics at all three Mach numbers mentioned above. Furthermore, considering the correspondence between the statistical effect of multiscale eddy events stochastically sampled in ODT and the effect of actual multiscale turbulent motions, a mechanism for Reynolds number effects is revealed by analyzing interactions between the multiscale eddy events from the ODT perspective. Evidence shows that the large-eddy motions in the outer region, rather than the small ones in the inner region, contribute to the Reynolds number effects when all these motions are plotted in inner-scaled units.
Aeroacoustic characteristics of multi-directional wing under the wing-in-ground effect
Authors: Lai Chenguang , Tan Liangkui , Zhu Yujie , Zhu Shengji , Obayashi Shigeru
Published: May 2022

Characteristics of the generation and propagation of aerodynamic noise are unique to conventional ground vehicles or aircraft due to the wing-in-ground (WIG) phenomenon. This study numerically examines the aeroacoustic characteristics of a multi-directional wing under the WIG effect with different values of clearance. The flow field was simulated by using a large eddy simulation for six groups of wings with different clearances and one group of wings in free space, at a freestream velocity of 0.3 Ma and an angle of attack of 5°. Acoustic simulations were carried out for each condition by using Möhring's analogy, and the acoustic analysis was based on details of the flow field. A multi-vortex system was generated at the trailing edge of the wing when the clearance was lower than 0.2 C. It consisted of an oscillating attached vortex that expanded and shrank with continuous changes in energy, and two periodically shedding vortices were formed that generated a strong wall-bound vortex street downstream of the wing after shedding. An analytical approach was used to simultaneously analyze different dominant frequencies in each region of the sound field. We conclude that different intensities of the WIG effect led to remarkable differences in the characteristic frequency of aerodynamic noise induced by the multi-directional wing. The characteristic frequencies of aerodynamic noise of the multi-directional wing with a low clearance (clearance ≤ 0.2 C) were mainly caused by the wall-bound vortex street while those at a high clearance (clearance ≥ 0.4 C) were mainly caused by vortices on the wingtip.
Chickpea and lentil show little genetic variation in emergence ability and rate from deep sowing, but small-sized seed produces less vigorous seedlings
Authors: Rich Sarah M. , Berger Jens , Lawes Roger , Fletcher Andrew
Published: May 2022

Context Germination and emergence are key to successful annual crop establishment. Emergence rate depends on germination rate, sowing depth, and rate of pre-emergent shoot elongation. The rate at which a shoot grows prior to emerging from the soil becomes significant when crops such as chickpea (Cicer arietinum L.) and lentil (Lens culinaris Medik.) are deep sown to utilise moisture below the conventional sowing zone. Aims In seeds of contrasting size, we aimed to compare the ability of chickpera and lentil varieties to emerge from deep sowing. Here we describe genetic variation for epicotyl growth rate, and phenotypic variation for epicotyl and root growth rates and biomass partitioning, of chickpea and lentil, as they relate to seed size. We further assess the impact of deep sowing and soil type on emergence, establishment and yield of the two species. Methods Epicotyl elongation rates, root growth and seedling biomass partitioning were determined in controlled environment studies, using soil tubes. Field trials were conducted on two different soil types at two sowing depths. Key results Most of the variance in epicotyl growth rate could be attributed to species rather than variety. Although epicotyl emergence was faster in lentil, chickpea epicotyl growth rates were higher than those in lentils and unrelated to seed size, whereas growth rates in lentils were weakly correlated to seed size (r = 0.31). Root development and epicotyl diameter appeared to be traded for maintenance of growth in smaller seeds of both species. In the field, sowing depth did not affect emergence, establishment or yield of chickpeas at either site. Deeper sowing resulted in minor reductions in emergence of lentil at one site, although biomass and yield were not affected. Conclusions Emergence of both crops was unaffected by deep sowing (to at least 200 mm) under controlled environment and sandy field conditions. There was minimal genetic variation for the measured parameters within a species. Seed size was of little importance for emergence rate; however, shoot growth rate from small seeds was maintained by reducing seedling vigour. Implications Seed size should be considered when deep sowing lentils in order to maintain high seedling vigour. Further work is needed to understand how environmental factors influence seedling emergence from depth.
Geographical variations in genetic group composition, life-history traits, and statolith shape for
Authors: Ching Tzu-Yun , Yagishita Naoki , Yamaguchi Atsuko , Wang Chia-Hui , Chen Chih-Shin
Published: May 2022

Context Sepioteuthis cf. lessoniana is widely distributed in the coastal waters of the Indo-Pacific region and is a crucial fisheries resource along its distributional range. At least four lineages of Sepioteuthis have been identified in the western Pacific region; however, their biological information remains unclear. Aims In this study, the genetic groups of Sepioteuthis spp. in the southwestern Japan and northern Taiwan was examined using molecular markers, and the life-history traits and statolith morphology of the genetic groups were investigated. Methods A total of 137 and 205 squid individuals from Japan and Taiwan, respectively, were examined. Key results Three genetic groups of Sepioteuthis (S. sp. 1, sp. 2, and sp. 2A) were identified based on molecular evidence in both areas, among which Sepioteuthis sp. 2 was dominant in Japan (87%), whereas Sepioteuthis sp. 1 was dominant in Taiwan (70%). For the same genetic group, the mantle length, average growth rate, and size and age at maturity were greater for the squid in Japan than those in Taiwan. The statolith exhibited a wider lateral dome and longer rostrum for the squid in Taiwan than those in Japan. Conclusions This study indicated the variations in the life-history traits and statolith shapes of the squid were greater between geographic populations (Japan and Taiwan) than among the genetic groups, which suggested that environmental effects on life-history traits and statolith shape of squid were greater than genetic effects. Implications The results of this study provide insights into the population structure of Sepioteuthis spp. in the Northwest Pacific region, which is relevant for the sustainable management of the squid fisheries.
Quality TV and cultural origin
Authors: Abellán Sergio , Bormann Daniel Candel , Sáez de Adana Francisco , García Alejandro
Published: May 2022

Quality TV is a multi-layered phenomenon that often expresses itself through its formal qualities. This article asks to what extent form also depends on cultural origin. It compares the Spanish historical seriesIsabel(RTVE) and the Anglo-AmericanThe Crown(Netflix) by subjecting their narrative and medium-specific styles to a mixed method analysis. Despite similar authorial intentions,Isabelinvests in action and dialogue andThe Crownin cinematic style; furthermore,Isabel’s teleological and political narrative contrasts withThe Crown’s fragmented, more private narrative. While both series ingeniously adapt their telling to their historical periods, the Spanish understanding of history as a feat of memorization simplifies the narrative to thicken factual density, whereas the more metacognitive Anglo-American approach to history ensures a multi-level reading of the account, which is more in line with quality TV.
Sara Wickström: The forces controlling our cell fate
Authors: Morgado-Palacin Lucia
Published: May 2022

Sara Wickström combines biophysics, next-generation sequencing, and basic cell biology to investigate how cellular forces regulate the fate and position of stem cells within epithelial tissues.