bluuebunny/crossref_metadata_2025_split huggingface dataset:
A deep learning integrated radiomics model for identification of coronavirus disease 2019 using computed tomography
Authors: Zhang Xiaoguo , Wang Dawei , Shao Jiang , Tian Song , Tan Weixiong , Ma Yan , Xu Qingnan , Ma Xiaoman , Li Dasheng , Chai Jun , Wang Dingjun , Liu Wenwen , Lin Lingbo , Wu Jiangfen , Xia Chen , Zhang Zhongfa 
Published: February 2021

AbstractSince its first outbreak, Coronavirus Disease 2019 (COVID-19) has been rapidly spreading worldwide and caused a global pandemic. Rapid and early detection is essential to contain COVID-19. Here, we first developed a deep learning (DL) integrated radiomics model for end-to-end identification of COVID-19 using CT scans and then validated its clinical feasibility. We retrospectively collected CT images of 386 patients (129 with COVID-19 and 257 with other community-acquired pneumonia) from three medical centers to train and externally validate the developed models. A pre-trained DL algorithm was utilized to automatically segment infected lesions (ROIs) on CT images which were used for feature extraction. Five feature selection methods and four machine learning algorithms were utilized to develop radiomics models. Trained with features selected by L1 regularized logistic regression, classifier multi-layer perceptron (MLP) demonstrated the optimal performance with AUC of 0.922 (95% CI 0.856–0.988) and 0.959 (95% CI 0.910–1.000), the same sensitivity of 0.879, and specificity of 0.900 and 0.887 on internal and external testing datasets, which was equivalent to the senior radiologist in a reader study. Additionally, diagnostic time of DL-MLP was more efficient than radiologists (38 s vs 5.15 min). With an adequate performance for identifying COVID-19, DL-MLP may help in screening of suspected cases.
Combinatorial measurement of critical cooling rates in aluminum-base metallic glass forming alloys
Authors: Liu Naijia , Ma Tianxing , Liao Chaoqun , Liu Guannan , Mota Rodrigo Miguel Ojeda , Liu Jingbei , Sohn Sungwoo , Kube Sebastian , Zhao Shaofan , Singer Jonathan P. , Schroers Jan 
Published: February 2021

AbstractDirect measurement of critical cooling rates has been challenging and only determined for a minute fraction of the reported metallic glass forming alloys. Here, we report a method that directly measures critical cooling rate of thin film metallic glass forming alloys in a combinatorial fashion. Based on a universal heating architecture using indirect laser heating and a microstructure analysis this method offers itself as a rapid screening technique to quantify glass forming ability. We use this method to identify glass forming alloys and study the composition effect on the critical cooling rate in the Al–Ni–Ge system where we identified Al51Ge35Ni14 as the best glass forming composition with a critical cooling rate of 104 K/s.
Spin dynamics investigations of multifunctional ambient scalable Fe3O4 surface decorated ZnO magnetic nanocomposite using FMR
Authors: Pathak Saurabh , Verma Rajni , Singhal Sakshi , Chaturvedi Raghav , Kumar Prashant , Sharma Pragati , Pant R. P. , Wang Xu 
Published: February 2021

AbstractMicrowave spin resonance behavior of the Fe3O4 surface decorated ZnO nanocomposites (FZNC) has been investigated by ferromagnetic resonance (FMR). Modified hydrothermal method has been adopted to fabricate FZNC samples with Fe3O4 nanoparticles chains were used as seeds in the uniform magnetic field to decorate them on the surface of the ZnO nanoparticles in a unique configuration. Spin dynamics investigation confirms the transition of ZnO from diamagnetic to ferromagnetic as the sharp FMR spectra converts to the broad spectra with Fe3O4 nanoparticles incorporation. A single broad FMR spectra confirms that no isolated Fe3+ or Zn2+ ions exist which is also in agreement with XRD confirming suitable composite formation. Further, the increase in Fe3O4 concentration leads to decrease in g-value which is resulting from the internal field enhancement due to magnetic ordering. Also, various spin resonance parameters were calculated for the FZNC which provides a detail information about the magnetic ordering, exchange coupling and anisotropy. Elemental analysis confirms the presence of Fe and Zn simultaneously and transmission electron microscopy (TEM) image show the presence of Fe3O4 on the grain boundaries of ZnO which has been confirmed by taking high-resolution TEM and electron diffraction patterns on both sides of the interface. These unique structural configuration of the FZNC has tremendous potential in various magneto-optoelectronic, spintronics and electro-chemical applications.
Implementation and effectiveness of a multi-domain program for older adults at risk of cognitive impairment at neighborhood senior centres
Authors: Ng Pei Ern Mary , Nicholas Sean Olivia , Wee Shiou Liang , Yau Teng Yan , Chan Alvin , Chng Isaiah , Yap Lin Kiat Philip , Ng Tze Pin 
Published: February 2021

AbstractTo address the paucity of research investigating the implementation of multi-domain dementia prevention interventions, we implemented and evaluated a 24-week, bi-weekly multi-domain program for older adults at risk of cognitive impairment at neighborhood senior centres (SCs). It comprised dual-task exercises, cognitive training, and mobile application-based nutritional guidance. An RCT design informed by the Reach, Effectiveness, Adoption, Implementation, Maintenance framework was adopted. Outcome measures include cognition, quality of life, blood parameters, and physical performance. Implementation was evaluated through questionnaires administered to participants, implementers, SC managers, attendance lists, and observations. The program reached almost 50% of eligible participants, had an attrition rate of 22%, and was adopted by 8.7% of the SCs approached. It was implemented as intended; only the nutritional component was re-designed due to participants’ unfamiliarity with the mobile application. While there were no between-group differences in cognition, quality of life, and blood parameters, quality of life reduced in the control group and physical function improved in the intervention group after 24 weeks. The program was well-received by participants and SCs. Our findings show that a multi-domain program for at-risk older adults has benefits and can be implemented through neighborhood SCs. Areas of improvement are discussed.Trial registration: ClinicalTrials.gov NCT04440969 retrospectively registered on 22 June 2020.
Retinoic acid regulates erythropoietin production cooperatively with hypoxia-inducible factors in human iPSC-derived erythropoietin-producing cells
Authors: Katagiri Naoko , Hitomi Hirofumi , Mae Shin-Ichi , Kotaka Maki , Lei Li , Yamamoto Takuya , Nishiyama Akira , Osafune Kenji 
Published: February 2021

AbstractErythropoietin (EPO) is a crucial hormone for erythropoiesis and produced by adult kidneys. Insufficient EPO production in chronic kidney disease (CKD) can cause renal anemia. Although hypoxia-inducible factors (HIFs) are known as a main regulator, the mechanisms of EPO production have not been fully elucidated. In this study, we aimed to examine the roles of retinoic acid (RA) in EPO production using EPO-producing cells derived from human induced pluripotent stem cells (hiPSC-EPO cells) that we previously established. RA augmented EPO production by hiPSC-EPO cells under hypoxia or by treatment with prolyl hydroxylase domain-containing protein (PHD) inhibitors that upregulate HIF signals. Combination treatment with RA and a PHD inhibitor improved renal anemia in vitamin A-depleted CKD model mice. Our findings using hiPSC-EPO cells and CKD model mice may contribute to clarifying the EPO production mechanism and developing efficient therapies for renal anemia.
Hepatic connective tissue growth factor expression and regulation differ between non-steatotic and non-alcoholic steatotic livers from brain-dead donor
Authors: Yang Dong-Jing , Shi Ji-Hua , Xia Zong-Ping , Guo Wen-Zhi , Ahmed Mohammed Shakil , Zhang Shui-Jun 
Published: February 2021

AbstractAccurate evaluation of liver steatosis is required from brain-dead donors (BDDs) with nonalcoholic fatty liver disease (NAFLD). Our purposes were to investigate expression and regulation of connective tissue growth factor (CTGF) expression in livers from human and rat after brain death, and further evaluate its potential application. NAFLD and brain death models were established in rats. LX2 cells were cultured under hypoxia/reoxygenation. CTGF protein and mRNA levels were measured in liver samples from BDDs of human and rat by immunohistochemistry and reverse transcription-quantitative polymerase chain reaction. YAP-regulated CTGF expression was investigated in LX2 cells via YAP small interfering RNA and Verteporfin treatment. Blood CTGF level from BDDs was measured by enzyme-linked immunosorbent assay. After brain death, CTGF, transforming growth factor-β and YAP were overexpressed in non-alcoholic steatotic liver, whereas CTGF was downregulated in non-steatotic liver. Time-series analysis revealed that CTGF and YAP expression was comparable, as confirmed by inhibited YAP expression in LX2 cells. CTGF level and NAFLD activity were linearly correlated. CTGF expression and regulation differ between non-steatosis and nonalcoholic steatosis livers from BDDs. CTGF may be an important factor to evaluate graft quality from BDDs with NAFLD.
Apical debris extrusion during instrumentation of oval root canals in primary teeth using manual versus motorized files: an ex vivo study
Authors: Pawar Bhaggyashri A. , Pawar Ajinkya M. , Atram Jatin , Luke Alexander Maniangat , Bhardwaj Anuj , Kfir Anda , Metzger Zvi , Wahjuningrum Dian Agustin 
Published: February 2021

AbstractThis study aimed to assess the apical extrusion of debris during instrumentation of primary canines using three endodontic file types. Forty-five extracted primary canines were randomly assigned to three instrumentation groups (n = 15): Hand K-files; and the motorized Kedo-S files and XP-endo Shaper files. The apically extruded debris produced during the procedure was collected and dried in pre-weighed Eppendorf tubes, and the mass of debris was calculated. The time required for the endodontic procedure was also recorded. Analysis of variance (ANOVA) and Tukey’s post hoc test were used with a significance level set at 5%. XP-endo Shaper and Kedo-S files extruded significantly less debris compared with hand K-files with means of 0.84 ± 0.31 and 1.20 ± 0.67 mg respectively, compared to 2.13 ± 0.31 mg (p < 0.0001). No significant difference was found between the two motorized files. Less time was required to complete the procedure with the XP-endo Shaper compared to the hand K-files (p < 0.0001) and Kedo-S files (p < 0.0001). Within the limitations of the present study, it may be concluded that motorized files extruded less debris and required less instrumentation time compared to traditional K-files, which could benefit paediatric patients with root canal treatment needs.
Compact lightweight imager of both gamma rays and neutrons based on a pixelated stilbene scintillator coupled to a silicon photomultiplier array
Authors: Boo Jihwan , Hammig Mark D. , Jeong Manhee 
Published: February 2021

AbstractDual particle imaging, in which both neutrons and gamma-rays in the environment can be individually characterized, is particularly attractive for monitoring mixed radiation emitters such as special nuclear materials (SNM). Effective SNM localization and detection benefits from high instrument sensitivity so that real-time imaging or imaging with a limited number of acquired events is enabled. For portable applications, one also desires a dual particle imager (DPI) that is readily deployable. We have developed a hand-held type DPI equipped with a pixelated stilbene-silicon photomultiplier (SiPM) array module and low sampling-rate analog-to-digital converters (ADCs) processed via a multiplexed readout. The stilbene-SiPM array (12 × 12 pixels) is capable of effectively performing pulse shape discrimination (PSD) between gamma-ray and neutron events and neutron/gamma-ray source localization on the imaging plane, as demonstrated with 252Cf neutron/gamma and 137Cs gamma-ray sources. The low sampling rate ADCs connected to the stilbene-SiPM array module result in a compact instrument with high sensitivity that provides a gamma-ray image of a 137Cs source, producing 6.4 μR/h at 1 m, in less than 69 s. A neutron image for a 3.5 × 105 n/s 252Cf source can also be obtained in less than 6 min at 1 m from the center of the system. The instrument images successfully with field of view of 50° and provides angular resolution of 6.8°.
Diaporthe species causing stem gray blight of red-fleshed dragon fruit (Hylocereus polyrhizus) in Malaysia
Authors: Huda-Shakirah Abd Rahim , Kee Yee Jia , Wong Kak Leong , Zakaria Latiffah , Mohd Masratul Hawa 
Published: February 2021

AbstractThis study aimed to characterize the new fungal disease on the stem of red-fleshed dragon fruit (Hylocereus polyrhizus) in Malaysia, which is known as gray blight through morphological, molecular and pathogenicity analyses. Nine fungal isolates were isolated from nine blighted stems of H. polyrhizus. Based on morphological characteristics, DNA sequences and phylogeny (ITS, TEF1-α, and β-tubulin), the fungal isolates were identified as Diaporthe arecae, D. eugeniae, D. hongkongensis, D. phaseolorum, and D. tectonendophytica. Six isolates recovered from the Cameron Highlands, Pahang belonged to D. eugeniae (DF1 and DF3), D. hongkongensis (DF9), D. phaseolorum (DF2 and DF12), and D. tectonendophytica (DF7), whereas three isolates from Bukit Kor, Terengganu were recognized as D. arecae (DFP3), D. eugeniae (DFP4), and D. tectonendophytica (DFP2). Diaporthe eugeniae and D. tectonendophytica were found in both Pahang and Terengganu, D. phaseolorum and D. hongkongensis in Pahang, whereas D. arecae only in Terengganu. The role of the Diaporthe isolates in causing stem gray blight of H. polyrhizus was confirmed. To date, only D. phaseolorum has been previously reported on Hylocereus undatus. This is the first report on D. arecae, D. eugeniae, D. hongkongensis, D. phaseolorum, and D. tectonendophytica causing stem gray blight of H. polyrhizus worldwide.
Recovery of tropical marine benthos after a trawl ban demonstrates linkage between abiotic and biotic changes
Authors: Wang Zhi , Leung Kenneth M. Y. , Sung Yik-Hei , Dudgeon David , Qiu Jian-Wen 
Published: February 2021

AbstractBottom trawling, which is highly detrimental to seabed habitats, has been banned in some jurisdictions to mitigate the problems of habitat destruction and overfishing. However, most reports of ecosystem responses to trawling impacts originate from temperate latitudes, focusing on commercial species, and recovery of invertebrate macrobenthos from trawl ban has hardly ever been studied in the tropics. In Hong Kong (lat. 22.4°N), a history of intensive trawling with various types of gears has long degraded coastal ecosystems. To facilitate the recovery of fisheries resources and associated benthic ecosystems, the Government of the Hong Kong Special Administrative Region implemented a territory-wide trawl ban on December 31, 2012. Comparison of surveys conducted in June 2012 (before the trawl ban) and June 2015 (2.5 years after the ban) revealed higher organic contents in sediment and lower suspended-solid loads in water column, as well as a significant increase in site-based abundance, species richness, functional diversity and among-site similarity of macrobenthos after the trawl ban. Our results suggest that the imposition of a trawl ban can be an effective measure for biodiversity conservation in tropical coastal waters.
Mixed supply function‐Cournot equilibrium model of futures and day‐ahead electricity markets
Authors: Banaei Mohsen , Oloomi‐buygi Majid , Raouf‐Sheybani Hani , Khooban Mohammad‐Hassan 
Published: February 2021

AbstractFutures contract is one of the useful financial derivatives for hedging the market players against the risks of undesirable price fluctuations in the power systems. Market players are allowed to trade electric energy in both futures and day‐ahead electricity markets. The behaviour of market players in each market affects the prices and power transactions of the other market. In this study, the mutual impacts of the futures and day‐ahead electricity markets are studied using a mixed supply function‐Cournot equilibrium model. The day‐ahead electricity market is modelled by Cournot method and futures market negotiations are modelled by the supply function method. The proposed model considers the strategic behaviour of consumers in the futures market, mark‐to‐marketing (MTM) settlement in the futures market, dynamics of market players’ behaviour during the trading period, and transmission system constraints. An upgraded risk management method is also introduced and evaluated. The proposed model is applied to a test system and the impacts of different parameters on the results are discussed.
Response of a grid forming wind farm to system events, and the impact of external and internal damping
Authors: Roscoe Andrew , Knueppel Thyge , Da Silva Ricardo , Brogan Paul , Gutierrez Isaac , Elliott Douglas , Perez Campion Juan‐Carlos 
Published: February 2021

Following from smaller‐scale investigations of grid‐forming converter control applied to wind turbines in 2017–2018, this study describes a much larger trial involving an entire wind farm, owned and operated by ScottishPower Renewables. To the authors’ knowledge, this was the first UK converter‐connected wind farm to operate in grid‐forming mode, and the largest in the world to date. The 23‐turbine, 69 MW farm ran in the grid‐forming mode for 6 weeks, exploring inertia contributions between H = 0.2 s and H = 8 s. A number of unscheduled frequency disturbances occurred due to interconnector, combined cycle gas turbine (CCGT) and other trips, to which un‐curtailed turbines were able to respond. In addition, several deliberate tests were carried out. The turbines were able to provide a stable and appropriate response at relatively high inertia levels to the frequency events commonly occurring today. The captured responses stimulated a debate as to whether external damping power might be required in a grid‐forming converter, or whether internal damping is sufficient to allow stable and robust power‐sharing with parallel devices in all grid event scenarios. Analysis in this study suggests that, practically, internal damping is probably appropriate, and that any deficiency in external damping power can be more than mitigated by reactance and/or droop‐slope response‐time management in the grid‐forming converters.
Modeling the nonaxisymmetric structure in the HD 163296 disk with planet-disk interaction
Authors: Rodenkirch P. J. , Rometsch T. , Dullemond C. P. , Weber P. , Kley W. 
Published: February 2021

Context. High-resolution ALMA observations such as the DSHARP campaign have revealed a variety of rich substructures in numerous protoplanetary disks. These structures consist of rings, gaps, and asymmetric features. It has been debated whether planets can be accounted for among these substructures in the dust continuum. Characterizing the origin of asymmetries, as seen in HD 163296, might lead to a better understanding of planet formation and the underlying physical parameters of the system.
Aims. We test the possibility that the formation of the crescent-shaped asymmetry in the HD 163296 disk can be attributed to planet-disk interaction. The goal is to obtain constraints on planet masses, eccentricities, and disk viscosities. Furthermore, we test the reproducibility of the two prominent rings in the HD 163296 disk at 67 and 100 au.
Methods. We performed two-dimensional, multi-fluid, hydrodynamical simulations with the FARGO3D code, including three embedded planets in the setup. Dust is described via the pressureless fluid approach and distributed over eight size bins. The resulting grids were post-processed with the radiative transfer code RADMC-3D and CASA software to model the synthetic observations.
Results. We find that the crescent-shaped asymmetry can be qualitatively modeled with a Jupiter mass planet at a radial distance of 48 au. Dust is trapped in the trailing Lagrange point L5, preferably, with a mass of between 10 and 15 earth masses. The observation of such a feature constrains the level of viscosity and planetary mass. Increased values of eccentricity of the innermost Jupiter mass planet negatively impacts the stability of the crescent-shaped feature and does not reproduce the observed radial proximity to the first prominent ring in the system. Generally, a low level of viscosity (α ≤ 2 × 10−3) is necessary to allow for the existence of such a feature. Including dust feedback in the leading point, L4, can dominantly capture dust for dust grains with an initial Stokes number ≤ 3.6 × 10−2. In the synthetic ALMA observation of the model with dust feedback, two crescent-shaped features are visible. The observational results suggest a negligible effect on the part of dust feedback since only one such feature has been detected so far. The dust-to-gas ratio may thus be overestimated in the models. Additionally, the planet mass growth time scale does not strongly affect the formation of such asymmetries in the co-orbital region.
Helioseismological determination of the subsurface spatial spectrum of solar convection: Demonstration using numerical simulations
Authors: Böning Vincent G. A. , Birch Aaron C. , Gizon Laurent , Duvall Thomas L. 
Published: February 2021

Context. Understanding convection is important in stellar physics, for example, when it is an input in stellar evolution models. Helioseismic estimates of convective flow amplitudes in deeper regions of the solar interior disagree by orders of magnitude among themselves and with simulations.
Aims. We aim to assess the validity of an existing upper limit of solar convective flow amplitudes at a depth of 0.96 solar radii obtained using time-distance helioseismology and several simplifying assumptions.
Methods. We generated synthetic observations for convective flow fields from a magnetohydrodynamic simulation (MURaM) using travel-time sensitivity functions and a noise model. We compared the estimates of the flow amplitude with the actual value of the flow.
Results. For the scales of interest (ℓ < 100), we find that the current procedure for obtaining an upper limit gives the correct order of magnitude of the flow for the given flow fields. We also show that this estimate is not an upper limit in a strict sense because it underestimates the flow amplitude at the largest scales by a factor of about two because the scale dependence of the signal-to-noise ratio has to be taken into account. After correcting for this and after taking the dependence of the measurements on direction in Fourier space into account, we show that the obtained estimate is indeed an upper limit.
Conclusions. We conclude that time-distance helioseismology is able to correctly estimate the order of magnitude (or an upper limit) of solar convective flows in the deeper interior when the vertical correlation function of the different flow components is known and the scale dependence of the signal-to-noise ratio is taken into account. We suggest that future work should include information from different target depths to better separate the effect of near-surface flows from those at greater depths. In addition, the measurements are sensitive to all three flow directions, which should be taken into account.