bluuebunny/crossref_metadata_2025 huggingface dataset:
Concise total synthesis of opioids
Authors: He Huan , Xue Fanglin , Hu Zhao , Li Peng , Xiao Qian , Zhang Maojie , Xue Fei , Zhang Dan , Song Hao , Liu Xiao-Yu , Zheng Zhibing , Li Song , Zhong Wu , Qin Yong
Published: March 2022

A concise total synthesis of opioids is presented. The development of a regioselective Pd-catalyzed dearomatization arene coupling that requires no additional blocking groups allows for efficient access to a common thebaine core.
Computational study of Cu-catalyzed 1,2-hydrocarboxylation of 1,3-dienes with CO2: Pauli repulsion-controlled regioselectivity of Cu–Bpin additions
Authors: Hu Yanlei , Hu Lingfei , Gao Han , Lv Xiangying , Wu Yan-Bo , Lu Gang
Published: March 2022

The detailed mechanism of Cu-catalyzed 1,2-hydrocarboxylation of 1,3-dienes and origin of Cu-boryl additions have been investigated.
Enhanced mechanical quality factor of BiScO3–PbTiO3piezoelectric ceramics using glass composition
Authors: Shi Hongwei , Wang Zujian , Yang Xiaoming , Su Rongbing , Long Xifa , He Chao
Published: March 2022

The mechanical quality factorQmof BS–PT ceramics increased to 90 and the thermal depolarization temperatureTdremained above 300 °C after GeO2doping.
Room temperature tunable multicolor phosphorescent polymers for humidity detection and information encryption
Authors: Gao Yulei , Di Xiang , Wang Fenfen , Sun Pingchuan
Published: March 2022

A polymer with tunable multicolor was prepared via copolymerizing a phosphor with concentration dependent luminescence and acrylamide based on chemical crosslinking and hydrogen bonding interactions for humidity detection and information encryption.
The porous transport layer in proton exchange membrane water electrolysis: perspectives on a complex component
Authors: Yuan Xiao-Zi , Shaigan Nima , Song Chaojie , Aujla Mantaj , Neburchilov Vladimir , Kwan Jason Tai Hong , Wilkinson David P. , Bazylak Aimy , Fatih Khalid
Published: March 2022

The Ti-based PTL materials used in PEMWEs are reviewed. A compendium of attributes of PTLs is established. Impact of the PTL/CL interface on cell performance is examined. Correlation between the PTL properties and cell performance is investigated.
l-Cysteine as a reducing/capping/gel-forming agent for the preparation of silver nanoparticle composites with anticancer properties
Authors: Vishnevetskii Dmitry V. , Mekhtiev Arif R. , Perevozova Tatyana V. , Ivanova Alexandra I. , Averkin Dmitry V. , Khizhnyak Svetlana D. , Pakhomov Pavel M.
Published: March 2022

Novel supramolecular bioactive hydrogels, containing silver nanoparticles, with tunable properties were synthesized using only the simplest amino acid l-cysteine and silver salt.
Discovery of lead low-potential radical candidates for organic radical polymer batteries with machine-learning-assisted virtual screening
Authors: Li Cheng-Han , Tabor Daniel P.
Published: March 2022

Lead candidate radicals for use in radical polymer batteries are discovered by virtual screening with low computational footprint, chemistry-informed machine learning methods.
The locations of triphenylamine and tetraphenylethene on a cyclohexyl ring define a luminogen as an AIEgen or a DSEgen
Authors: Zhang Yuzhu , Ding Aixiang , Guo Shengmei , He Felicia , Kong Lin , Duan Rui-Huan , Yang Jiaxiang
Published: March 2022

Luminogens with distinct photophysical properties were synthesized by attaching TPE and TPA on a saturated cyclohexyl ring in an isolated fashion, demonstrating the effectiveness of the concept of “aryl isolation” in engineering AIEgens and DSEgens.
Structure–properties of small donor–acceptor molecules for homojunction single-material organic solar cells
Authors: Terenti Natalia , Giurgi Gavril-Ionel , Crişan Andreea Petronela , Anghel Cǎtǎlin , Bogdan Alexandra , Pop Alexandra , Stroia Ioan , Terec Anamaria , Szolga Lorant , Grosu Ion , Roncali Jean
Published: March 2022

Small donor–acceptor molecules combining arylamine donor blocks with various acceptors have been synthesized and evaluated as active materials in homojunction single material organic solar cells.
Drug repurposing in silico screening platforms
Authors: Mullins Jonathan G.L.
Published: March 2022

Over the last decade, for the first time, substantial efforts have been directed at the development of dedicated in silico platforms for drug repurposing, including initiatives targeting cancers and conditions as diverse as cryptosporidiosis, dengue, dental caries, diabetes, herpes, lupus, malaria, tuberculosis and Covid-19 related respiratory disease. This review outlines some of the exciting advances in the specific applications of in silico approaches to the challenge of drug repurposing and focuses particularly on where these efforts have resulted in the development of generic platform technologies of broad value to researchers involved in programmatic drug repurposing work. Recent advances in molecular docking methodologies and validation approaches, and their combination with machine learning or deep learning approaches are continually enhancing the precision of repurposing efforts. The meaningful integration of better understanding of molecular mechanisms with molecular pathway data and knowledge of disease networks is widening the scope for discovery of repurposing opportunities. The power of Artificial Intelligence is being gainfully exploited to advance progress in an integrated science that extends from the sub-atomic to the whole system level. There are many promising emerging developments but there are remaining challenges to be overcome in the successful integration of the new advances in useful platforms. In conclusion, the essential component requirements for development of powerful and well optimised drug repurposing screening platforms are discussed.
Design of a circularly polarized microstrip slot antenna using Minkowski fractal by the characteristic mode theory
Authors: Khajevandi Amir , Oraizi Homayoon
Published: March 2022

In this paper, the Minkowski fractal is used for the design of a microstrip slot antenna by the characteristic mode theory, whereby the radiation mode generating the desired radiation patterns is excited. The right‐hand circular polarization (RHCP) antenna is first designed and then the method of polarization reversal from RHCP to left‐hand circular polarization is presented by the design of the feed system. The FR‐4 substrate is used for the design of the slot antenna at 2.45 GHz. Also, the frequency spectrum of ISM includes that of WiFi, which has a single feed port. The use of Minkowski fractal has resulted in 0.28λ0 × 0.28λ0 miniaturization of the slot antenna. For the proof of concept, a prototype model of the proposed slot antenna is simulated, designed, fabricated and measured, which shows good agreement between the simulation results and measurement data.
Eigenmode analysis of perturbations in the primordial medium at and before recombination
Authors: Nelson A. H.
Published: March 2022

Context. Anisotropies of the cosmic microwave background are thought to be due to perturbations of the primordial medium, which, post recombination, lead to the formation of galaxy clusters and galaxies

Aims. The perturbation wave modes of the primordial medium at and before recombination, consisting of a fully ionised baryonic plasma, a strong black body radiation field, and cold dark matter, are analysed.

Methods. We use the linear perturbation theory of the relativistic equations of motion, utilising a strict thermodynamic equilibrium model that relates the radiation energy density to the plasma temperature.

Results. It is shown that a wave mode corresponding to the postulated baryon acoustic waves exists with a phase velocity close to the speed of light, but the participation of the dark matter in this mode is very small. Instead, the dark matter has its own dominant mode in the form of gravitational collapse, with very little participation by the baryonic plasma.

Conclusions. In view of this very weak coupling between baryons and dark matter, the initial conditions postulated for computer simulations of large-scale structure and galaxy formation – which assume that after recombination, when galaxy formation is getting underway, baryon and dark matter density perturbations are spatially coincident and are equal in terms of fractional amplitude – may be unjustified. Additionally, the possible non-coincidence of baryon and dark matter perturbations at the last scattering surface has implications for the analysis of cosmic microwave background anisotropies.
Ionization of He II in star-forming galaxies by X-rays from cluster winds and superbubbles
Authors: Oskinova Lidia M. , Schaerer Daniel
Published: March 2022

The nature of the sources powering nebular He II emission in star-forming galaxies remains debated, and various types of objects have been considered, including Wolf-Rayet stars, X-ray binaries, and Population III stars. Modern X-ray observations show the ubiquitous presence of hot gas filling star-forming galaxies. We use a collisional ionization plasma code to compute the specific He II ionizing flux produced by hot gas and show that if its temperature is not too high (≲2.5 MK), then the observed levels of soft diffuse X-ray radiation could explain He II ionization in galaxies. To gain a physical understanding of this result, we propose a model that combines the hydrodynamics of cluster winds and hot superbubbles with observed populations of young massive clusters in galaxies. We find that in low-metallicity galaxies, the temperature of hot gas is lower and the production rate of He II ionizing photons is higher compared to high-metallicity galaxies. The reason is that the slower stellar winds of massive stars in lower-metallicity galaxies input less mechanical energy in the ambient medium. Furthermore, we show that ensembles of star clusters up to ∼10−20 Myr old in galaxies can produce enough soft X-rays to induce nebular He II emission. We discuss observations of the template low-metallicity galaxy I Zw 18 and suggest that the He II nebula in this galaxy is powered by a hot superbubble. Finally, appreciating the complex nature of stellar feedback, we suggest that soft X-rays from hot superbubbles are among the dominant sources of He II ionizing flux in low-metallicity star-forming galaxies.
Rising sea level and increasing tropical cyclone frequency are threatening the population of San Andrés Island, Colombia, western Caribbean
Authors: Bernet Matthias , Torres Acosta Liliana
Published: March 2022

The Colombian island of San Andrés is a popular tourist destination located about 195 km offshore of the east coast of Nicaragua in the southwestern Caribbean Sea. Together with Providencia and Santa Catalina, San Andrés is part of the UNESCO Seaflower Biosphere Reserve. With a 26 km2 surface area and 78 000 inhabitants, San Andrés is one of the most densely populated islands in the Caribbean with on average ∼ 3000 inhabitants/km2. The majority of the population and the mass tourism are concentrated in the low-elevation (0.5–6 m) areas, particularly in the north and along the east coast of the island. These areas are prone to flooding during storm events such as hurricanes Eta and Iota in 2020. A review of the geological, environmental and the socio-economic situation of the island, and the record of tropical cyclones since 1911, shows why the local population has become increasingly vulnerable to storm events and rising sea level. Tropical cyclones may form locally in the southwestern Caribbean or originate in the eastern Caribbean/Atlantic Ocean. The latter tend to be stronger and cause more damage when they reach San Andrés. The HURDAT2 dataset shows that the frequency of storm events affecting San Andrés has increased in recent decades, with six storms over the past 20 years, including three category 4-5 hurricanes since 2007. Increasing storm frequency and intensity may be linked to increasing sea surface temperatures caused by anthropogenic global warming, although the changes described here may be limited to a relatively small geographical region, as opposed to representing basin wide tropical cyclone behavior. The growing population density since the 1950s has augmented the potential for disaster.
Quarante ans d’évolution du foncier dans le périmètre irrigué de Nong Waï, Thaïlande du Nord-Est : de l’espérance à l’impasse
Authors: Formoso Bernard
Published: March 2022

Dans les années 1960, le gouvernement thaïlandais mit en œuvre un programme de développement rural qui comprenait la création d’infrastructures d’irrigation dans le Nord-Est. L’article traite de l’évolution des usages du foncier au sein du plus ancien des périmètres irrigués mis en service à l’époque – celui de Nong Waï – sur la base d’enquêtes échelonnées sur 40 ans dans un village proche de la ville de Khon Kaen. Il montre que, si dans les années 1980 l’irrigation a permis des gains de productivité en lien avec la révolution verte, plusieurs facteurs se sont conjugués depuis pour entraver l’achat et le transfert intergénérationnel des terres. Un processus de désagrarianisation sans dépaysanisation est en cours, où la terre conserve sa fonction de valeur refuge mais régresse comme facteur de production. L’agriculture n’est plus la raison première du transfert de propriété du foncier irrigué dans le village périurbain et l’on observe une conversion croissante de celui-ci en terrains d’habitation.
Production System Modelling Methodologies of an Open Pit Mine
Authors: Semmar Atae , Machkour Nadia , Amalik Hafsa , Elouazguiti Mohamed , Medromi Hicham
Published: March 2022

Open pit mines experience several challenges and constraints in the management of mining operations and processes. The heterogeneity of the infrastructures and the complexity of the physical and managerial systems highlight these various challenges. The creation of a generic system that can drive but at the same time models in a dynamic logic all these constraints and elements assume a major complexity. In addition, the modelling allows the implementation of real-time decision-making components and increases the responsiveness of the system. This paper presents six modelling methodologies of the production system, namely Open System Architecture for Computer Integrated Manufacturing, GRAI Integrated Methodology, Purdue Enterprise Reference Architecture, Generalized Enterprise Reference Architecture and Methodology, Zachman and Model Based System Engineering. Based on the multi-criteria analysis, we have shown that the Modelling Based System Engineering is the most adapted methodology in the case of open pit mines but this method knows a lack of agility in the system. Our system will use a methodology based on Model Based System Engineering and will consider the agility of the system.
A Survey on Network Intrusion Detection using Convolutional Neural Network
Authors: Kaissar Antanios , Nassif Ali Bou , Injadat MohammadNoor
Published: March 2022

Nowadays Artificial Intelligence (AI) and studies dedicated to this field are gaining much attention worldwide. Although the growth of AI technology is perceived as a positive development for the industry, many factors are being threatened. One of these factors is security, especially network security. Intrusion Detection System (IDS) which provides real-time network security has been recognized as one of the most effective security solutions. Moreover, there are various types of Neural Networks (NN) approaches for IDS such as ANN, DNN, CNN, and RNN. This survey mainly focuses on the CNN approach, whether individually used or along with another technique. It analyses 81 articles that were carefully investigated based on a specific criterion. Accordingly, 28 hybrid approaches were identified in combination with CNN. Also, it recognized 21 evaluation metrics that were used to validate the models, as well as 12 datasets.
Machine learning and novel ophthalmologic biomarkers for Alzheimer’s disease screening: Systematic Review
Authors: Bourkhime Hind , Qarmiche Noura , Omari Mohammed , Bahra Nassiba , Tachfouti Nabil , EL Fakir Samira , Otmani Nada
Published: March 2022

Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disease that leads to dementia and eventual death, the reason why screening is so beneficial in its early stages. Recent evidence suggests that memory and vision impairments are closely linked to Alzheimer’s disease. Moreover, assessing vision disorders may improve early detection and treatment of dementia. Therefore, some research has been conducted on screening for AD disease using new machine learning (ML) techniques on novel ophthalmologic biomarkers data.

Objective: To summarize existing findings on machine learning models exploring eye changes data to predict cognitive decline in the context of AD.

Methods: Systematic review of original research between January 2016 and August 2021. A search covered two databases on (Scopus) and (PubMed).

Results: From 104 search results, 13 articles were selected after using the eligibility criteria: 5 machine learning models used retinal texture data, 5 models included eye movement data, 2 proposed models used iris change data, and 1 proposed model used corneal nerve loss data.

Conclusion: Promising results are reported in almost all 13 studies, but very few have been implemented in research or clinical practice. The principal constraints in this area are limited standardization and comparability of results..
Performances prediction in Wireless Sensor Networks: A survey on Deep learning based-approaches
Authors: Eljakani Yassin , Boulouz Abdellah , ben Salah Mohamed , El Hachemy Said
Published: March 2022

The dynamism and successive changes in the distribution of nodes are among the important characteristics of wireless sensor networks (WSNs). To adapt with those changes, network designers frequently have to configure multiple parameters for each layer on WSN architecture (i.e physical, medium access control, network, and application layer). This tuning has an important impact on the network performances (e.g packet loss, energy efficiency, throughput, network lifetime, etc). However, finding the optimal configuration is the main challenge. Deep learning (DL) based on neural network layers can be used to extract patterns from high-dimensional data provided by sensor nodes. In this paper, we survey the most recent DL approaches which aim to predict WSN performances by finding the pattern on the network parameters (such as transmission power level, MAC protocol type, spectrum availability, congestion points, etc.). Moreover, we classify the studied articles by considering the targeted network layer or cross-layer. This paper can be considered as a starting point for researchers to review the recent DL applications on the optimization of WSNs performances based on multiple network parameters.
Benchmarking of the Conductance Increment Method and its improved versions
Authors: Isknan Ismail , Asbayou Abdellah , Ihlal Ahmed , Bouhouch Lahoussine
Published: March 2022

To increase the performance of a photovoltaic (PV) system, a circuit using MPPT (Maximum Power Point Tracking) technology must be used. There are several algorithms proposed in the literature and they need to be compared to select the best performing MPPT technology for a specific application or to make recommendations for future MPPT research. This article presents a benchmarking the most widely used MPPT algorithms, namely the “INC_C” (Classical Incremental Conductance), the “INC_AM” (Modified Adaptive Incremental Conductance). The comparative study presented in this work will confirm that “INC_AM≫ is the best MPPT technique to improve the efficiency of a PV system.
A sight on defect detection methods for imbalanced industrial data
Authors: Chaabi Meryem , Hamlich Mohamed
Published: March 2022

Product defect detection is a challenging task, especially in situations where is difficult and costly to collect defect samples. Which make it quite difficult to apply supervised algorithms as their performances decrease by training the model on imbalanced data. To tackle this problem, researchers used data augmentation and one-class classification to detect defects in industrial areas. In this paper, we list defect detection applications for imbalanced industrial data and we report the benefits and limitation of those methods.
Speech analysis for the detection of Parkinson’s disease by combined use of empirical mode decomposition, Mel frequency cepstral coefficients, and the K-nearest neighbor classifier
Authors: Boualoulou N. , Nsiri B. , Drissi T. Belhoussine , Zayrit S.
Published: March 2022

Parkinson’s disease (PD) is one of the neurodegenerative diseases. The neuronal loss caused by this disease leads to symptoms such as lack of initiative, depressive states, psychological disorders, and impairment of cognitive functions as well as voice dysfunctions. This paper aims to propose a system of automatic recognition of Parkinson’s disease by voice analysis. In this system, we are based on a database of 38 recordings, 20 people with Parkinson’s disease and 18 healthy people pronounce the vowel /a/.at first, we have decomposed the vocal signal of each patient by the Empirical Mode Decomposition (EMD), then, we extract from 1 to 12 coefficients of the Mel Frequency Cepstral Coefficients (MFCC), to obtain the voiceprint from each voice sample, we compressed the frames by computing their average value. At the end of the classification, we have used the validation scheme “holdout” as well as the K-nearest neighbor (KNN) classifier, the performance of this classification gives accuracy up to 86,67% when applied to 80% of the database as training data.
Study on selective plugging characteristics and oil displacement mechanism of microsphere in porous media
Authors: Yuan Bo , Chen Yan , Ning Kai , Wei Jun , Xu Liang , Zhang Weiyi , Li Fang , Wu Junyi
Published: March 2022

Microspheres are widely used as profile control and water plugging products at present. However, the current research on microspheres is mainly focused on oil displacement experiments. In order to solve this problem, based on the Bohai sea in the BZ of inhomogeneous reservoir conditions, this article has done the matching study on particle size and hole roar and the seepage research in porous medium by means of particle size analysis, pressure tests, single-phase block experiments, and the double tube parallel oil displacement experiments, revealing the characteristics of oil & water selective plugging and the mechanism of oil displacement in porous media. The results show that the average particle size of the microspheres increases from 4.857μm to 24.53μm, and the maximum expansion factor reaches 5.03 times after 72h of swelling in BZ25 oilfield water at 75 C. In the two-pipe parallel oil flooding experiment with the permeability of 1000mD and 3000mD respectively, the comprehensive recovery rate after the first water flooding is 28.06%, and the two-pipe average recovery rate is increased by 1.58% after the injection of 2000ppm microsphere with 0.3PV, and there is no significant increase in oil displacement efficiency. The comprehensive recovery rate reached 38.6% and increased by 8.99% after 4PV of subsequent water flooding, indicating that microsphere flooding effectively improved the water sweep efficiency of subsequent injection.
Study on ammonium-promoted phenol-formaldehyde-based gel for enhanced oil recovery and its seepage characteristics in porous media
Authors: Wang Hongshen , Wang Jinlin , Shi Duansheng , Yang Lei , Han Ruoshui , Yin Fujian , Han Yimin , Liu Siqi
Published: March 2022

The phenol-formaldehyde crosslinker has low reactivity at low temperature, and is not easy to occur crosslinking reaction. In order to solve this problem, a kind of ammonium-promoted phenol-formaldehyde-based gel profile control agent was constructed which has the reactivity at low temperature. The basic formula is 0.30%~0.60%polymer, 0.01%resorcinol, 0.60% phenol-formaldehyde crosslinker and 0.10% ammonium salt. The results showed that the final gelling time was 6 days at 65°C, and the final gelling strength could reach G grade. In response to the problem that the plugging characteristics of ammonium-promoted phenol-formalde-hydebased gel are still unclear, the seepage characteristics of the phenol-formaldehyde-based gel in porous media are revealed by physical simulation of sand-pack. The research shows that the plugging rate of porous media with permeability of 2000 mD reaches 98%, the breakthrough pressure gradient is greater than 1.35 MPa/m.
Bei eingeschränkter Nierenfunktion erhöhtes Risiko für kontrastmittelinduziertes Nierenversagen
Authors: van der Giet Markus
Published: March 2022

In der Vergangenheit wurde ein historisch bekanntes Risiko für ein akutes Nierenversagen (AKI) nach intravenöser Kontrastmittelapplikation durchaus überschätzt. Trotzdem bleibt bei Patienten mit Nierenfunktionsstörungen ein Restrisiko. In der vorliegenden Studie wurde deshalb untersucht, ob eine Kontrastmittelapplikation während einer Computertomografie (CT) mit einem höheren Risiko für ein AKI assoziiert ist. Zudem wurde analysiert, ob die kontrastmittelgestützte CT zu einer höheren Rate von Dialysepflichtigkeit führt im Vergleich zu Patienten ohne Kontrastmittelexposition.
Hilfsmittel richtig einsetzen – Teilhabe am Leben fördern
Authors: Endres Julia
Published: March 2022

Hilfsmittel zur Verbesserung der Mobilität und somit auch zur Teilhabe am Leben sind aus der neurologischen Rehabilitation nicht mehr wegzudenken. Es gibt viele Möglichkeiten, unsere Patienten in ihren unterschiedlichen Defiziten zu unterstützen und das Gehen zu fördern.
Das Allgäu wird zur Sahelzone
Authors: Knoblauch Hans
Published: March 2022

Die Klimakrise mit ihren bereits heute deutlichen Auswirkungen in vielen Lebensbereichen, z. B. Hitzewellen, Flutkatastrophen etc. nimmt in ihren Konsequenzen für die Gesundheit, der medialen Darstellung und öffentlichen Wahrnehmung eine zunehmende Bedeutung ein. Ausgehend davon, dass Symptome psychischer Erkrankungen in ihrer inhaltlichen Ausgestaltung abhängig vom Zusammenspiel soziokultureller und biografischer Faktoren sind, wird in dieser Kasuistik der Verlauf der Behandlung eines 59-jährigen Mannes mit einer schweren depressiven Episode und der wahnhaften Überzeugung, dass sich die Landschaft des Allgäus aufgrund der Klimakrise in eine Landschaft wie die Sahelzone verwandelt, beschrieben.
Efficient bias robust regression for time series factor models
Authors: Martin R. Douglas , Xia Daniel Z.
Published: March 2022

We introduce a robust regression estimator for time series factor models called the mOpt estimator. This estimator minimizes the maximum bias due to outlier generating distribution deviations from a standard normal errors distribution model, and at the same time has a high normal distribution efficiency. We demonstrate the efficacy of the mOpt estimator in comparison with the non-robust least squares (LS) estimator in applications to both single factor and multifactor time series models. For the case of single factor CAPM models we compared mOpt and LS estimates for cross sections of liquid stocks from the CRSP database in each contiguous two-year interval from 1963 to 1980. The results show that absolute differences between the two estimates greater than 0.3 occur for about 18% of the stocks, and differences greater than 0.5 occur for about 7.5% of the stocks. Our application of the mOpt estimator to multifactor models focuses on fitting the Fama-French 3-factor and the Fama-French-Carhart 4-factor models to weekly stock returns for the year 2008, using both the robust t-statistics associated with the mOpt estimates and a new statistical test for differences between the mOpt and LS coefficients. The results demonstrate the efficacy of the mOpt estimator in providing better model fits than the LS estimates, which are adversely influenced by outliers. Finally, since model selection is an important aspect of time series factor model fitting, we introduce a new robust prediction errors based model selection criterion called the Robust Final Prediction Error (RFPE), which makes natural use of the mOpt regression estimator. When applied to the 4-factor model, the RFPE finds as the best subset model the one that contains the Market, SMB and MOM factors, not the three Fama-French factors Market, SMB and HML. We anticipate that RFPE will prove to be quite useful for model selection of time series factor models.
Facial recognition as a tool to identify Roman emperors: towards a new methodology
Authors: Ramesh Darshan Srirangachar , Heijnen Sam , Hekster Olivier , Spreeuwers Luuk , de Wit Florens
Published: March 2022

Portraits of Roman emperors are traditionally recognised by their unique coiffure patterns, a method that runs the risk of ignoring portraits that do not cohere to the standardised image of the emperor. This article investigates whether it is possible to recognise and distinguish emperors using the facial features of their portraits. By using a technique called transfer learning, it utilises existing deep-learning facial recognition models, augmented with images of Roman imperial portraits, to provide a new empirical foothold in the debate of Roman emperor recognition. The results of the experiments demonstrate that by only a limited amount of training, such a so-called “pre-trained” model (i.e., InceptionResnet-V1) is able to correctly classify most images in the dataset of Roman emperors. As such, this article has made a first step towards applying facial recognition models to the study of ancient imperial portraiture.
Stability of steady states in ferromagnetic rings
Authors: Carbou G. , Moussaoui M. , Rachi R.
Published: March 2022

In this paper, we consider a one-dimensional model of ferromagnetic rings, taking into account curvature and anisotropy effects. We describe relevant stationary configurations of the magnetization and we investigate their stability in the Liapunov sense.
Single-pulse all-optical partial switching in amorphous DyxCo1−x and TbxCo1−x with random anisotropy
Authors: Hu Zexiang , Besbas Jean , Smith Ross , Teichert Niclas , Atcheson Gwenael , Rode Karsten , Stamenov Plamen , Coey J. M. D.
Published: March 2022

Repeated uniform switching of the magnetization of thin films of ferrimagnetic amorphous Gdx(FeCo)1−x in response to single fast laser pulses is well established. Here, we report unusual toggle switching in thin films of sperimagnetic amorphous DyxCo1−x and TbxCo1−x with x ≈ 0.25 irradiated with single 200 fs pulses of 800 nm laser light. The samples have strong local random anisotropy due to the non-S state rare earth. The compensation temperature of the films is ≤180 K, and their Curie temperature is ≈500 K. They are largely switched by the first pulse, and subsequent pulses lead to partial re-switching of a decreasing amount of the irradiated area, with a granular structure of submicrometer regions of switched and unswitched material. Individual switched regions about 700 nm in size are observed around the edge of the irradiated spots where the fluence is at the threshold for switching. Results are discussed in terms of a random anisotropy model where the ratio of local anisotropy to exchange is temperature dependent.
Airflow-induced P(VDF-TrFE) fiber arrays for enhanced piezoelectric energy harvesting
Authors: Kim Yong-Il , Kim Dabin , Jung Jihun , Kim Sang-Woo , Kim Miso
Published: March 2022

Piezoelectricity, flexibility, light weight, and biocompatibility of piezoelectric polymer fibers are the desired attributes for energy harvesting and sensing in wearable and biomedical applications. However, the relatively insufficient piezoelectric performance of piezoelectric polymers remains an issue. Here, we demonstrate a considerable increase in P(VDF-TrFE) fiber alignment via electrospinning with a rapidly rotating collector, which substantially enhanced the piezoelectric performance of the fiber mat over a large area. Considering the relationship between the airflow induced near the collector surface and the rotating speed, the collectors with different geometries were systematically compared in terms of the degree of alignment, fiber morphology, and the resulting crystalline electroactive phases of the fibers produced by each collector. We found that the strong airflow induced by the rapid rotation of the modified drum collector contributes to the preferential fiber orientation by pulling and stretching over a large area, which led to an increase in the crystalline electroactive β-phase content responsible for piezoelectricity. As a result, a maximum voltage of 116.6 V and maximum output power of 13.6 µW were achieved using a flexible piezoelectric device comprising a large-area, highly aligned P(VDF-TrFE) fiber mat produced from a modified drum collector at a significantly high speed. This work provides a facile but powerful solution for the wide use of piezoelectric polymer fibers.
Enhanced nanoparticle sensing by mode intensity in a non-reciprocally coupled microcavity
Authors: Jiang Shuo , Xiao Zhisong , Li Wenxiu , Chen Tuoyu , Li Jincheng , Huang Anping , Zhang Hao
Published: March 2022

Optical microcavities operating at exceptional points have a strong mode splitting response to small perturbations such as nanoparticles. The detection limit is susceptible to mode linewidth so that small nanoparticles cannot induce a mode splitting in the transmission or reflection spectrum. Here, we propose a sensing mechanism to avoid the limitation of mode linewidth on the detection limit. We show that a microcavity with two Bragg gratings generates bright and dark modes due to completely non-reciprocal coupling. Since the two modes are not degenerate initially, utilizing the dark mode intensity as a readout scheme significantly reduces the detection limit for small perturbations. This work opens up the way toward a new class of ultrasensitive nanoparticle sensor.
Anomalous transparency at 1064 nm of a freely expanding gas cylinder in vacuum during fast electric explosion of thin metal wires
Authors: Sarkisov G. S.
Published: March 2022

Laser shadowgrams of exploding metal wires in a vacuum show the anomalous transparency of a completely evaporated wire core for a probe beam with a wavelength of 1064 nm. Simultaneous shadowgrams at 532 nm show significant light attenuation. The anomalous transparency for laser radiation at a wavelength of 1064 nm is highly likely due to the Rayleigh scattering of the probing beam by metal atoms. Our experimental results can be explained under the assumption of a strongly non-equilibrium state of an expanding gas cylinder with a non-uniform density.
Simulation study on adsorption characteristics of lignite to mine gas
Authors: Lun Jiayun , Sun Yinghao , Ding Junling , Song Huijie , Zhang Zhaohong
Published: March 2022

This study aims at investigating the adsorption mechanism of CO2, CH4, CO, and N2 mine gases and oxygen-containing functional groups in lignite. Thus, density functional theory and grand canonical Monte Carlo simulation methods were used to determine the adsorption energy, configuration, isotherm, and isosteric heat as well as the diffusion coefficient of gas in lignite. The results showed that the adsorption capacity of CO2 molecules and oxygen-containing functional groups was greater than that of CH4, CO, and N2. The order of the absolute value of the adsorption energy of each oxygen-containing functional group of each gas molecule on the lignite surface model was as follows: carboxyl > hydroxyl > carbonyl > ether bond. The adsorption isotherms of the four gases (CO2, CH4, CO, and N2) in the lignite molecular structure model were consistent with the Langmuir adsorption isotherm model. The relationship between the adsorption amount of the four gases in the lignite structure model was CO2 > CH4 > CO > N2. In addition, the adsorption capacity of the four gases decreased as the temperature increased. The CO2 isosteric heat of adsorption was considerably greater than that of CH4, CO, and N2, indicating that the adsorption capacity of the lignite molecular structure model for CO2 was considerably stronger than that of CH4, CO, and N2. The CO2 diffusion coefficient showed the slowest change with the temperature increase, whereas the N2 self-diffusion coefficient showed the fastest change. The following diffusion activation energy sequence was obtained: CO2 < CH4 < CO < N2.
Super-resolution acoustic imaging
Authors: Chen Wangqiao , Jiang Hanbo , Huang Xun
Published: March 2022

This work reports a super-resolution acoustic imaging method that inverses source distribution, strength, and structure in three-dimensional space. The nonlinear coupling process between a low-frequency sound field and a high-frequency plane wave is endowed to break the resolution limit. The reconstructed results for different source strengths and frequencies demonstrate the capability of the proposed method. The results show that the proposed method is very suitable for low-frequency source imaging, which could strengthen the super-resolution analysis capability of acoustic imaging tests and, consequently, lead to deepened physical insights into various propulsion systems in underwater and aerospace systems.
Critical behavior of the classical spin-1 Ising model for magnetic systems
Authors: Zivieri R.
Published: March 2022

In this work, the critical properties of the classical spin-1 Ising Hamiltonian applied to magnetic systems characterized by the first-neighbors biquadratic exchange, the anisotropy and the external magnetic field contributions are theoretically investigated. The first-neighbors bilinear exchange interaction is set equal to zero. For magnetic systems the bicubic exchange interaction must be set equal to zero as it would break the time-reversal invariance of the exchange Hamiltonian. To determine the critical behavior, the spin-1 Ising Hamiltonian is mapped onto the spin-1/2 Ising Hamiltonian by using the Griffith’s variable transformation. The critical surface of a 2D square magnetic lattice is determined in the parameter space as a function of the magnetic parameters and the phase transition occurring across it is quantitatively discussed by calculating, for each spin, the free energy and the magnetization. The free energy of the 2D square magnetic lattice, described via the three-state spin-1 Ising model, is obtained from an empirical expression of the partition function recently proposed for a spin-1/2 Ising model in an external magnetic field and applied to a 2D magnetic lattice. These results could pave the way to numerical simulations and to measurements able to confirm the analytical predictions.
Near room temperature magnetocaloric properties in Ni deficient (Mn0.525Fe0.5)Ni0.975Si0.95Al0.05
Authors: Khan Mahmud , Das Ranjit Chandra , Casey Jacob , Reese Brandon L. , Akintunde Babajide , Pathak Arjun K.
Published: March 2022

We present an experimental study on the crystalline, magnetic, and magnetocaloric properties of Ni deficient (Mn-rich) (Mn0.525Fe0.5)Ni0.975Si0.95Al0.05. The study has been performed by x-ray diffraction, scanning electron microscopy, and dc magnetization measurements. X-ray diffraction measurements showed that the sample primarily exhibited the orthorhombic structure at room temperature. The coupled structural and ferromagnetic transition occurred at ∼338 K, which is significantly larger than ∼320 K observed in (Mn0.50Fe0.5)NiSi0.95Al0.05. Maximum magnetic entropy changes of ΔSM = −9.5 and 25 J kg−1K−1 for ΔH = 20 kOe and 50 kOe, respectively, have been observed in the material. Large refrigeration capacities of 60 J/kg and 160 J/kg for field changes of ΔH = 20 kOe and 50 kOe, respectively, have also been observed.
Features of the electronic transport of topological semimetal PtSn4 and WTe2 single crystals
Authors: Perevalova A. N. , Naumov S. V. , Podgornykh S. M. , Marchenkova E. B. , Chistyakov V. V. , Huang J. C. A. , Marchenkov V. V.
Published: March 2022

PtSn4 and WTe2 single crystals were grown, and the resistivity was studied in the temperature range from 4.2 to 80 K in various magnetic fields up to 10 T in detail. It is suggested that the observed quadratic temperature dependence of the electrical resistivity at low temperatures in zero field can be due to, in addition to electron-electron scattering, the “electron-phonon-surface” interference scattering mechanism. The transition from high effective magnetic fields to weak ones, which is observed in compensated conductors with a closed Fermi surface, was proposed as a possible explanation for the minimum on the temperature dependence of the resistivity of PtSn4 and WTe2 in a magnetic field. The values of the mean free path of current carriers were estimated in these materials.
Population demography of the Tasmanian short-beaked echidna (
Authors: Lunn Tamika J. , Nicol Stewart C. , Buettel Jessie C. , Brook Barry W.
Published: March 2022

Deriving estimates of demographic parameters and the processes driving them is crucial for identifying wildlife management options. The short-beaked echidna (Tachyglossus aculeatus) is the most widely distributed native Australian mammal, yet little is known of its population dynamics due to its cryptic nature. Consequently, assessment of the impacts of climate and threats on echidna populations has been difficult. We analyse 19 years (1996–2014) of mark–recapture data to estimate survival and reproductive rates of a Tasmanian population of short-beaked echidna, and to evaluate the influence of regional weather patterns on its demographics. Population size showed high year-to-year variation, ranging from 1 to 40 echidnas km2 across the study area. Known-fate modelling of radio-tracked individuals suggested that climatic conditions impacted survival; average longevity was estimated at 16.7 years but only 4.8 years when the total spring/summer rainfall was below 125 mm, and 6.25 in years when temperatures more frequently exceeded 32°C. Recruitment, estimated from Pradel analyses, was low in the population (β = 0.08) and not significantly affected by climate. These results are the first quantitative estimates of climate effects, survival, and recruitment for this species, and suggest that climate-enhanced drying and temperature increase would pose a threat to echidna populations in Tasmania.
The affordances of metaphor for diachronic corpora & discourse analysis
Authors: Taylor Charlotte
Published: March 2022

This paper examines the utility of metaphor as an investigative tool in “long-distance” corpora and discourse studies. I show that metaphor is both important for understanding discourses and useful for diachronic analysis because it allows us to abstract out above the purely lexical level, enabling comparison across contexts where the same concept could be lexicalised differently. The case-study is concerned with the oft-discussed metaphor ofmigrants are waterin the UK-basedTimesnewspaper from 1800–2018 and the conventionalisation and evaluative patterns are presented. The findings confirm that thewatermetaphor has an extensive discourse history regarding how migration is represented in the UK press, but also that evaluations may differ significantly. The paper shows how metaphor can provide a way to find discourse evaluations and framings across different time periods. The use of second-order collocates illustrates how corpus tools can help re-contextualise data to ensure interpretation heeds contemporary framings.
Framing the political conflict discourse in Chinese media
Authors: Zhu Lili
Published: March 2022

Individuals perceive the real world via interpretive schema, and actively classify and interpret their life experiences into what are defined as frames, to make sense of the world around them. Why certain frames are chosen can be explored from the cognitive and communicative perspective. In this light, this study explores how the Chinese news media frame the coverage on Sino-US trade dispute, discursively legitimizing their ideological stance and action. The case study demonstrates that Chinese media exploit multifarious frames to construct the Chinese national identity, which correspondingly and strategically highlight such frames (Cooperation, Health, Journey) as conform to culture value or render the audience empathy. It is suggested to construct political conflict discourse via strategic choices of appropriate social, moral or cultural frames to reframe the dispute. Chinese media can also deploy agenda-setting to enhance political communication.
Cross-linguistic patterns in the lexicalisation of bring and take
Authors: Margetts Anna , Haude Katharina , Himmelmann Nikolaus P. , Jung Dagmar , Riesberg Sonja , Schnell Stefan , Seifart Frank , Sheppard Harriet , Wegener Claudia
Published: March 2022

This study investigates the linguistic expression ofbringandtakeevents and more generally of the semantic domain of directed caused accompanied motion (‘directed CAM’) across a sample of eight languages of the Pacific and the Americas. Unlike English, the majority of languages in our sample do not lexicalise directed CAM events by simple verbs, but rather encode the defining meaning components – caused motion, accompaniment, and directedness – in morphosyntactically complex constructions. The study shows a high degree of crosslinguistic diversity, even among closely related languages. Meaning components are contributed to directed CAM expressions by a mix of lexical semantics, morphosyntax, and pragmatic means. The study proposes a text-based, semantic typology of directed CAM events by drawing on corpus data from endangered languages.
Ecological significance and risks of mineral licks to mammals in a nature reserve on the Eastern Qinghai-Tibet Plateau
Authors: He Xingcheng , Wen Zhixin , Wang Yujin , Feijó Anderson , Fu Qiang , Ran Jianghong
Published: March 2022

Mineral licks are important components of terrestrial ecosystems that have special value to the maintenance of fluid balance of mammals, by providing them with essential mineral nutrients such as sodium, calcium, and magnesium. In the Anzihe Nature Reserve, southwest China, seven species of ungulates and one species of primates were frequently observed visiting the mineral licks in high densities. As a consequence, mineral licks have attracted illegal hunters and facilitated the spread of parasites and diseases, leading to a depletion of local populations. Therefore, we suggest that regions with abundant mineral licks should be designated as key protected areas in the Anzihe Nature Reserve and relevant zones for animal health surveillance.
A universal formula for the density of states in theories with finite-group symmetry
Authors: Harlow Daniel , Ooguri Hirosi
Published: March 2022

In this paper we use Euclidean gravity to derive a simple formula for the density of black hole microstates which transform in each irreducible representation of any finite gauge group. Since each representation appears with nonzero density, this gives a new proof of the completeness hypothesis for finite gauge fields. Inspired by the generality of the argument we further propose that the formula applies at high energy in any quantum field theory with a finite-group global symmetry, and give some evidence for this conjecture.