bluuebunny/crossref_metadata_2025_split huggingface dataset:
Classification of power quality disturbances based on KF‐ML‐aided S‐transform and multilayers feedforward neural networks
Authors: Xi Yanhui , Li Zewen , Tang Xin , Zeng Xiangjun 
Published: September 2020

Classifying power quality (PQ) disturbances is one of the most important issues for PQ control. The S‐transform (ST)‐based neural networks in conjunction with Kalman filter based on maximum likelihood (KF‐ML) are presented for classification of PQ disturbances. To accurately extract features in high‐noise cases, the KF‐ML is used to remove noise from the original distorted waveform. Then, ST technique is used to extract the significant features of disturbances. Finally, a classifier based on multilayers feedforward neural networks can accurately recognise various types of PQ disturbances. Six simulated single disturbances and six complex ones with different noise levels are tested for the sensitivity to noise. Classification results show that the classification accuracy of the proposed method is more than 95% even in 20 dB high‐noise condition, and also validate the superiority of strong rejection to noises. Comparison studies between the proposed method and other classification methods are also reported to show the advantages of the proposed approach.
How to disentangle geometry and mass-loss rate from AGB-star spectral energy distributions
Authors: Wiegert J. , Groenewegen M. A. T. , Jorissen A. , Decin L. , Danilovich T. 
Published: September 2020

Context. High-angular-resolution observations of asymptotic giant branch (AGB) stars often reveal non-spherical morphologies for the gas and dust envelopes.
Aims. We aim to make a pilot study to quantify the impact of different geometries (spherically symmetric, spiral-shaped, and disc-shaped) of the dust component of AGB envelopes on spectral energy distributions (SEDs), mass estimates, and subsequent mass-loss rate (MLR) estimates. We also estimate the error made on the MLR if the SED is fitted by an inappropriate geometrical model.
Methods. We use the three-dimensional Monte-Carlo-based radiative-transfer code RADMC-3D to simulate emission from dusty envelopes with different geometries (but fixed spatial extension). We compare these predictions with each other, and with the SED of the AGB star EP Aqr that we use as a benchmark since its envelope is disc-like and known to harbour spiral arms, as seen in CO.
Results. The SEDs involving the most massive envelopes are those for which the different geometries have the largest impact, primarily on the silicate features at 10 and 18 μm. These different shapes originate from large differences in optical depths. Massive spirals and discs appear akin to black bodies. Optically thick edge-on spirals and discs (with dust masses of 10−4 and 10−5 M⊙) exhibit black-body SEDs that appear cooler than those from face-on structures and spheres of the same mass, while optically thick face-on distributions appear as warmer emission. We find that our more realistic models, combined spherical and spiral distributions, are 0.1 to 0.5 times less massive than spheres with similar SEDs. More extreme, less realistic scenarios give that spirals and discs are 0.01 to 0.05 times less massive than corresponding spheres. This means that adopting the wrong geometry for an AGB circumstellar envelope may result in a MLR that is incorrect by as much as one to two orders of magnitude when derived from SED fitting.
DeGaS-MC: Dense Gas Survey in the Magellanic Clouds
Authors: Galametz M. , Schruba A. , De Breuck C. , Immer K. , Chevance M. , Galliano F. , Gusdorf A. , Lebouteiller V. , Lee M. Y. , Madden S. C. , Polles F. L. , van Kempen T. A. 
Published: September 2020

Context. Understanding the star-forming processes is key to understanding the evolution of galaxies. Investigating star formation requires precise knowledge of the properties of the dense molecular gas complexes where stars form and a quantification of how they are affected by the physical conditions to which they are exposed. The proximity, low metallicity, and wide range of star formation activity of the Large and Small Magellanic Clouds (LMC and SMC) make them prime laboratories to study how local physical conditions impact the dense gas reservoirs and their star formation efficiency.
Aims. The aim of the Dense Gas Survey for the Magellanic Clouds (DeGaS-MC) project is to expand our knowledge of the relation between dense gas properties and star formation activity by targeting the LMC and SMC observed in the HCO+(2−1) and HCN(2−1) transitions.
Methods. We carried out a pointing survey targeting two lines toward ∼30 LMC and SMC molecular clouds using the SEPIA180 instrument installed on the Atacama Pathfinder EXperiment (APEX) telescope. We performed a follow-up mapping campaign of the emission in the same transition in 13 star-forming regions. This first paper provides line characteristic catalogs and integrated line-intensity maps of the sources.
Results. HCO+(2−1) is detected in 20 and HCN(2−1) in 8 of the 29 pointings observed. The dense gas velocity pattern follows the line-of-sight velocity field derived from the stellar population. The three SMC sources targeted during the mapping campaign were unfortunately not detected in our mapping campaign but both lines are detected toward the LMC 30Dor, N44, N105, N113, N159W, N159E, and N214 regions. The HCN emission is less extended than the HCO+ emission and is restricted to the densest regions. The HCO+(2−1)/HCN(2−1) brightness temperature ratios range from 1 to 7, which is consistent with the large ratios commonly observed in low-metallicity environments. A larger number of young stellar objects are found at high HCO+ intensities and lower HCO+/HCN flux ratios, and thus toward denser lines of sight. The dense gas luminosities correlate with the star formation rate traced by the total infrared luminosity over the two orders of magnitude covered by our observations, although substantial region-to-region variations are observed.
Dental Care during COVID-19 Outbreak: A Web-Based Survey
Authors: Faccini Melissa , Ferruzzi Fernanda , Mori Aline Akemi , Santin Gabriela Cristina , Oliveira Renata Cristina , Oliveira Ricardo Cesar Gobbi de , Queiroz Polyane Mazucatto , Salmeron Samira , Pini Nubia Inocencya Pavesi , Sundfeld Daniel , Freitas Karina Maria Salvatore 
Published: September 2020

Abstract
Objective This survey aimed to assess the effects of coronavirus disease 2019 (COVID-19) on elective and urgency/emergency dental care and dentists concerned.
Materials and Methods A web-based survey was performed using Google forms questionnaire sent to dentists in Brazil. Questions included: personal information, type of dental care provided during quarantine, if emergencies increased, the dental office biosafety routine, among others. The levels of concern about the impact of quarantine on dental care and patient oral health conditions and the economic impact on dental practices were evaluated using a 0- to 10-point scale. Statistical analysis included descriptive, percentages, one-way ANOVA, Tukey, and chi-square tests.
Results During quarantine, 64.6% of the dentists attended only urgency/emergency treatments, while 26.1% maintained routine appointments, and 9.3% closed the dental offices. A higher percentage of dentists from the least affected states continued routine dental treatment; dentists were younger and presented a significantly lower level of concern about dental treatments and oral health conditions of their patients. An increase in urgency/emergency procedures was reported by 44.1% of the dentists, mostly due to the unavailability of routine/elective dental care and increased patient anxiety and stress. The main causes of urgency/emergency appointments were toothache, dental trauma, and broken restorations, besides the breakage of orthodontic appliances and temporomandibular disorders. Dentists reported a high level of concern about the economic impact caused by quarantine.
Conclusions The pandemic/quarantine has negatively affected the clinical routine. Personal protection/hygiene care must be adopted and reinforced by dental professionals/staff to make dental procedures safer.
Current Clinical Dental Practice Guidelines and the Financial Impact of COVID-19 on Dental Care Providers
Authors: Ali Saqib , Farooq Imran , Abdelsalam Maha , AlHumaid Jehan 
Published: September 2020

AbstractThe novel coronavirus disease 2019 (COVID-19) has been acknowledged as a pandemic by the World Health Organization (WHO). The aim of this study was to review guidelines issued by different health regulatory bodies amid the COVID-19 outbreak and financial constraints faced by dentists globally. Relevant papers and news articles were identified in Google Scholar and PubMed. The search was made using the keywords “COVID-19,” “COVID-19 and dentistry,” and “the financial impact of COVID-19 on dentistry.” Studies and news articles published in languages other than English were excluded and a final selection of 53 relevant studies, guideline documents, and news articles were made. The outbreak of COVID-19 has affected all businesses including general dental practices, which are suffering huge financial losses as they have been advised to provide only emergency dental care. These recommendations should be appreciated as a positive step but they have caused serious financial implications for dental practices. It can be concluded that current dental practice globally is limited to the provision of emergency treatments only. This step is appreciative, but has resulted in huge financial losses sustained by dental care providers (DCPs) worldwide. The governments and health regulatory bodies of developed countries are trying to help dental practices to evolve from this troublesome situation, but there is no visible policy from the underdeveloped world that could help the DCPs to save their practices from closing down due to the financial constraints.
The Retromolar Space and Wisdom Teeth in Humans: Reasons for Surgical Tooth Extraction
Authors: Kaseh Abed El , Shayeb Maher Al , Kuduruthullah Syed , Gulrez Nadeem 
Published: September 2020

AbstractObjective This article explores the problem of developing pathologies in the retromolar region. Findings can serve a framework for disease prevention and for the improvement of the quality of life of patients. The present study aims to justify the possibility of utilizing morphometric methods to foresee problems in the eruption of third molars.Materials and Methods A comprehensive morphometric study of the lower jaw and facial skeleton involves 100 skulls of Homo sapiens to identify the anatomical causes of problems with wisdom teeth eruption. All said skulls are divided in two groups: I: skulls with intact dentition; II: skulls with impacted third molars.Results This work allows detecting abnormalities in the eruption of the third molar with high probability of success. The abnormalities in point are considered not only those associated with the generally accepted parameters but also those that occur in the leptoprosopic face cases.Conclusions Face type and the structural features of the facial skeleton play a significant role in the abnormal eruption of the lower third molar.
Socioeconomic determinants of farm household land allocation for grass pea production in North Wollo Zone of Amhara region, Ethiopia
Authors: Damene Shimeles , Guta Dawit Diriba , Assen Mohammed , Satyal Poshendra 
Published: September 2020

AbstractGrass pea (Lathyrus sativus) is widely cultivated and consumed in Ethiopia, where its overconsumption has caused cases of lathyrism. Despite this fact, there are limited empirical studies carried out in Ethiopia on the factors driving household decision to grow grass pea and intensity of land allocation to its production. Therefore, this study was focused on exploring the determinants of smallholder farmers’ land allocation to grass pea production in two districts of Ethiopian highlands. Household survey, focus group discussions and key informant interviews were used as data collection methods. These were followed by statistical analysis of quantitative data with SPSS and thematic analysis of qualitative data. The study used the Heckman selection model to investigate the determinants of household’s intensity of land use for grass pea production. The data revealed that farmers in the study area annually allocated about 26% of their farm plots size to grass pea production. Household’s landholding size, age of household head and the head’s primary school attendance have statistically significant and positive effect on the size of land allocation to grass pea production. Farmers also switched to grass pea production due to its tolerance to drought and waterlogged soils. These all encouraged grass pea production and consumption by humans, which has resulted in lathyrism in the study area. Household access to health and farm extension services had negative and statistically significant effect on land allocation to grass pea production. Based on the findings, it is concluded that better access to markets, educational opportunities, credit facilities, family planning and farm extension services are needed to increase household awareness on crop diversification and enhance technology uptake and financial capacity. Consequently, this can help local people reduce allocation of land to grass pea production and decrease its consumption, thereby preventing the risk of lathyrism incidence.
Scaling relationships for the elastic moduli and viscosity of mixed lipid membranes
Authors: Kelley Elizabeth G. , Butler Paul D. , Ashkar Rana , Bradbury Robert , Nagao Michihiro 
Published: September 2020

Significance
Life requires a delicate balance between cell membrane rigidity and fluidity to define cell boundaries yet enable cell deformation, growth, and division. Here, we bridge the molecular and macroscopic scales with neutron scattering techniques to demonstrate how the material properties of model lipid membranes are readily tuned by the constituent lipid composition. Mixing lipids leads to softer and less viscous membranes than predicted a priori from the pure component membrane properties. Instead, the dynamics are linked to the membrane structure and follow simple scaling relationships with the area per molecule. These results emphasize the importance of lipid packing and reveal the interwoven relationship between lipid membrane structure and dynamics.
Effect of hardening on electrical and magnetic properties of C-75 steel and characterization with multi-frequency inductance spectroscopy
Authors: Munjal Rohan , Wendler Frank , Leonhardt André , Birnbaum Peter , Kräusel Verena , Kanoun Olfa 
Published: September 2020

AbstractNon-destructive monitoring of metal hardness is important for process monitoring and product quality assessment. In this paper, a partially hardened metal sample is assessed in regards to physical effects using multi-frequency inductance spectroscopy. For this purpose, the influence of change of conductivity, permeability and stress on the inductance spectra are analyzed. To extract the numerical values of permeability, the measured inductance spectra are compared to the analytical inductance model. Statistical analysis with principal component analysis is conducted to fuse the spectral data into a single representative value. The results show the possibility to obtain information from different layers of the partially hardened sample, thus indicating a strong relationship between the measured inductance and restraint hardening.
Thermal conductivity and interfacial thermal resistance in the heterostructure of silicon/amorphous silicon dioxide: the strain and temperature effect
Authors: Gu Hanqing , Wang Jiuhong , Wei Xueyong , Wang Hairong , Li Zhibin 
Published: September 2020

Abstract
This article reports the thermal conduction properties of Si/a-SiO2 heterostructure with two different interfaces: weak and strong coupling strength through molecular dynamics simulation. The size and temperature dependencies on the interfacial thermal resistance of the weak coupling interface are larger than those of the strong coupling interface. The thermal conduction in Si/a-SiO2 shows strong anisotropy. The thermal conductivity, interfacial thermal resistance, and enhancement of the anisotropy can be modulated by changing the strains applied to the heterostructures. This work provides an optional way to design the silicon-based heterostructures considering heat insulation and heat dissipation.
A new phosphonium-based ionic liquid to synthesize nickel metaphosphate for hydrogen evolution reaction
Authors: Ying Hao , Zhang Chenyun , Chen Tingting , Zhao Xiaoning , Li Zhonghao , Hao Jingcheng 
Published: September 2020

Abstract
The electrochemical hydrogen evolution reaction (HER) is a promising strategy for production of hydrogen; however, it is still restricted by appropriate efficient and low-cost electrocatalysts. Herein, for the first time, the n-octylammonium hypophosphite, a kind of protic ionic liquid (IL), was used as a new phosphorus source for the manufacture of nickel metaphosphate (Ni2P4O12) electrocatalysts. In contrast to traditional multi-step fabrication processes, the n-octylammonium hypophosphite acted as both reactant and solvent to synthesize Ni2P4O12 by a one-step calcination approach. The obtained Ni2P4O12 as an alkaline HER catalyst required a low overpotential of 116 mV at −10 mA cm−2 and a small Tafel slope of 97 mV dec−1, comparable to the majority of reported Ni-based materials and other phosphate catalysts. Furthermore, this catalyst exhibited robust stability with no distinct attenuation of current density after a long-term durability test in 1 M KOH. Therefore, this task-specific IL strategy with a simple reaction system, reducing the occurrence of side reactions, provided a new perspective on design of high-efficiency metaphosphate electrocatalysts.
Temperature-dependent Raman modes of MoS2/MoSe2 van der Waals heterostructures
Authors: Öper Merve , Shehu Yahaya , Perkgöz Nihan Kosku 
Published: September 2020

Abstract
Two-dimensional (2D) monolayer transition metal dichalcogenides (TMDs) show extra-ordinary properties compared to their bulk forms, which has inspired a large number of researchers to investigate these materials recently. Design and fabrication of different combinations of 2D TMDs layers can allow for high-performance and novel heterostructure-based devices, of which the performance will depend also on their thermal properties. On the other hand, the temperature-dependent behavior of such heterolayers and their interaction at different temperatures is still not comprehensively studied in a wide temperature range. In this work, we have performed a systematical temperature-dependent (83 K—483 K) Raman spectroscopic analysis of the MoS2/MoSe2 van der Waals (vdW) heterostructures and discussed their stability. After the transfer process of the MoS2 monolayers onto the MoSe2/SiO2/Si, we annealed the samples, which is a commonly used process to increase the crystallinity. Associatively, the thermal annealing process leads to a decrease in the thermal coefficients of the E1
2g and A1g modes of MoS2 and MoSe2 monolayers. Our study shows that the peak positions of the Raman modes in the heterostructures redshift with an increase in temperature. Furthermore, the full width at half maximum (FWHM) of the E1
2g and A1g modes of the layers broaden at higher temperatures. This phenomenon is attributed to increasing phonon–phonon interactions and thermal expansion effects with the ascending temperature. To the best of our knowledge, for the first time, temperature-dependent Raman analysis of MoS2/MoSe2 vdW heterostructures before and after annealing are carried out; and peak positions, FWHMs, and thermal coefficients of the layers are extracted. We do not observe any deformation in the heterobilayer structure even at very low (83 K) or very high temperatures (483 K). This is the first step to confirm the durability of the MoS2/MoSe2 heterolayered devices under extreme temperatures by studying their thermal properties.
Gravitational wave imprint of new symmetry breaking *
Authors: Chao Wei , Cui Wen-Feng , Guo Huai-Ke , Shu Jing 
Published: September 2020

Abstract
It is believed that there are more fundamental gauge symmetries beyond those described by the Standard Model of particle physics. The scales of these new gauge symmetries are usually too high to be reachable by particle colliders. Considering that the phase transition (PT) relating to the spontaneous breaking of new gauge symmetries to the electroweak symmetry might be strongly first order, we propose considering the stochastic gravitational waves (GW) arising from this phase transition as an indirect way of detecting these new fundamental gauge symmetries. As an illustration, we explore the possibility of detecting the stochastic GW generated from the PT of

in the space-based interferometer detectors. Our study demonstrates that the GW energy spectrum is reachable by the LISA, Tianqin, Taiji, BBO, and DECIGO experiments only for the case where the spontaneous breaking of

is triggered by at least two electroweak singlet scalars.
Finite particle number description of neutron matter using the unitary correlation operator and high-momentum pair methods *
Authors: Wan Niu , Myo Takayuki , Xu Chang , Toki Hiroshi , Horiuchi Hisashi , Lyu Mengjiao 
Published: September 2020

Abstract
Using bare Argonne V4' (AV4'), V6' (AV6'), and V8' (AV8') nucleon–nucleon (NN) interactions, the nuclear equations of state (EOSs) for neutron matter are calculated with the unitary correlation operator and high-momentum pair methods. Neutron matter is described using a finite particle number approach with magic number

under a periodic boundary condition. The central short-range correlation originating from the short-range repulsion in the

interaction is treated by the unitary correlation operator method (UCOM), and the tensor correlation and spin-orbit effects are described by the two-particle two-hole (2p2h) excitations of nucleon pairs, where the two nucleons with a large relative momentum are regarded as a high-momentum (HM) pair. With increasing 2p2h configurations, the total energy per particle of the neutron matter is well-converged under this UCOM+HM framework. Comparing the results calculated with AV4', AV6', and AV8'

interactions, we demonstrate the effects of the short-range correlation, tensor correlation, and spin-orbit coupling on the density dependence of the total energy per particle of neutron matter. Moreover, the contribution of each Hamiltonian component to the total energy per particle is discussed. The EOSs of neutron matter calculated within the present UCOM+HM framework agree with the calculations of six microscopic many-body theories, especially the auxiliary field-diffusion Monte Carlo calculations.
Fast heating dissociation of

in heavy ion collisions at RHIC *
Authors: Liu Yunpeng , Chen Baoyi 
Published: September 2020

Abstract
By adopting the adiabatic assumption in the cooling process, we discuss a novel mechanism of

suppression that occurs due to the fast heating process at the early stage of the fireball, instead of its finite decay width in a finite temperature medium generated by heavy ion collisions. We calculate the transition probability after the fast heating dissociation as a function of the temperature of the medium and the nuclear modification factor in central collisions and find that the suppression is not negligible at RHIC, even if the width of

becomes zero.