bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deep learning and ensemble stacking technique for differentiating polypoidal choroidal vasculopathy from neovascular age-related macular degeneration
Authors: Chou Yu-Bai , Hsu Chung-Hsuan , Chen Wei-Shiang , Chen Shih-Jen , Hwang De-Kuang , Huang Yi-Ming , Li An-Fei , Lu Henry Horng-Shing 
Published: March 2021

AbstractPolypoidal choroidal vasculopathy (PCV) and neovascular age-related macular degeneration (nAMD) share some similarity in clinical imaging manifestations. However, their disease entity and treatment strategy as well as visual outcomes are very different. To distinguish these two vision-threatening diseases is somewhat challenging but necessary. In this study, we propose a new artificial intelligence model using an ensemble stacking technique, which combines a color fundus photograph-based deep learning (DL) model and optical coherence tomography-based biomarkers, for differentiation of PCV from nAMD. Furthermore, we introduced multiple correspondence analysis, a method of transforming categorical data into principal components, to handle the dichotomous data for combining with another image DL system. This model achieved a robust performance with an accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve of 83.67%, 80.76%, 84.72%, and 88.57%, respectively, by training nearly 700 active cases with suitable imaging quality and transfer learning architecture. This work could offer an alternative method of developing a multimodal DL model, improve its efficiency for distinguishing different diseases, and facilitate the broad application of medical engineering in a DL model design.
Sudden cardiac death risk in hypertrophic cardiomyopathy: comparison between echocardiography and magnetic resonance imaging
Authors: Śpiewak Mateusz , Kłopotowski Mariusz , Kowalik Ewa , Kubik Agata , Ojrzyńska-Witek Natalia , Petryka-Mazurkiewicz Joanna , Michalak Ewa , Mazurkiewicz Łukasz , Gawor Monika , Kożuch Katarzyna , Miłosz-Wieczorek Barbara , Grzybowski Jacek , Bilińska Zofia , Witkowski Adam , Klisiewicz Anna , Marczak Magdalena 
Published: March 2021

AbstractIn hypertrophic cardiomyopathy (HCM) patients, left ventricular (LV) maximal wall thickness (MWT) is one of the most important factors determining sudden cardiac death (SCD) risk. In a large unselected sample of HCM patients, we aimed to simulate what changes would occur in the calculated SCD risk according to the European HCM Risk-SCD calculator when MWT measured using echocardiography was changed to MWT measured using MRI. All consecutive patients with HCM who underwent cardiac MRI were included. MWT measured with echocardiography and MRI were compared, and 5-year SCD risk according to the HCM Risk-SCD calculator was computed using four different models. The final population included 673 patients [389 (57.8%) males, median age 50 years, interquartile range (36–60)]. The median MWT was lower measured by echocardiography than by MRI [20 (17–24) mm vs 21 (18–24) mm; p < 0.0001]. There was agreement between echocardiography and MRI in the measurement of maximal LV wall thickness in 96 patients (14.3%). The largest differences between echo and MRI were − 13 mm and + 9 mm. The differences in MWT by echocardiography and MRI translated to a maximal difference of 8.33% in the absolute 5-year risk of SCD, i.e., the echocardiography-based risk was 8.33% lower than the MRI-based estimates. Interestingly, 13.7% of patients would have been reclassified into different SCD risk categories if MRI had been used to measure MWT instead of echocardiography. In conclusion, although there was high general intermodality agreement between echocardiography and MRI in the MWT measurements, the differences in MWT translated to significant differences in the 5-year risk of SCD.
Effect of coronavirus lockdowns on the ambient seismic noise levels in Gujarat, northwest India
Authors: Roy Ketan Singha , Sharma Jyoti , Kumar Santosh , Kumar M. Ravi 
Published: March 2021

AbstractThe Covid-19 pandemic created havoc and forced lockdowns in almost all the countries worldwide, to inhibit social spreading. In India as well, as a precautionary measure, complete and partial lockdowns were announced in phases during March 25 to May 31, 2020. The restricted human activities led to a drastic reduction in seismic background noise in the high frequency range of 1–20 Hz, representative of cultural noise. In this study, we analyse the effect of anthropogenic activity on the Earth vibrations, utilizing ambient noise recorded at twelve broadband seismographs installed in different environmental and geological conditions in Gujarat. We find that the lockdowns caused 1–19 dB decrease in seismic noise levels. The impact of restricted anthropogenic activities is predominantly visible during the daytime in urban areas, in the vicinity of industries and/or highways. A 27–79% reduction in seismic noise ground displacement (drms) is observed in daytime during the lockdown, in populated areas. However, data from station MOR reveals a drastic decrease in drms amplitude both during the day (79%) and night times (87%) since factories in this area operate round the clock. The noise at stations located in remote areas and that due to microseisms, shows negligible variation.
An insight into the estimation of frost thermal conductivity on parallel surface channels using kernel based GPR strategy
Authors: Zhou Xuejun , Zhou Fangyuan , Naseri Maryam 
Published: March 2021

AbstractIn heat exchange applications, frost formation on the cold surface causes a decrease in the rate of heat transfer and growth in the pressure drop. Thus, the study on the frost thermal conductivity has a significant and vital place for the engineers and researchers dealing with the heat exchangers. In the literature, there is a lack of accurate and applicable methods for determination of frost thermal conductivity. Additionally, the high cost and difficulties of experimental works clarify the importance of computational and mathematical methods. The errors in the determination of frost thermal conductivity on parallel surface channels can cause inaccuracy in estimations of frost density and thickness. The main aim of present work is suggesting Gaussian Process Regression (GPR) models based on four different kernel functions for the estimation of frost thermal conductivity in terms of time, air velocity, relative humidity, air temperature, wall temperature, and frost porosity. To achieve this purpose, a total number of 57 frost thermal conductivity values has been collected. Comparing the suggested GPR models and other available computational methods express the quality of the developed models. The best predictive tool has been selected as a GPR model, including Matern kernel function with R2 values of 0.997 and 0.994 in training and testing phases, respectively. In addition, the effectiveness of discussing variables on frost thermal conductivity has been investigated by sensitivity analysis and showed that air temperature is the most effective parameter. The present work gives engineers an insight into frost thermal conductivity and the effective parameters in its determination.The significant advantage of present work is the accurate prediction of thermal conductivity by a brief knownledge in artificial intelligence.
Periconceptional nutrition with spineless cactus (Opuntia ficus-indica) improves metabolomic profiles and pregnancy outcomes in sheep
Authors: Rosales-Nieto César A. , Rodríguez-Aguilar Maribel , Santiago-Hernandez Francisco , Cuevas-Reyes Venancio , Flores-Najera Manuel J. , Vázquez-García Juan M. , Urrutia-Morales Jorge , Ghaffari Morteza Hosseini , Meza-Herrera César A. , González-Bulnes Antonio , Martin Graeme B. 
Published: March 2021

AbstractWe tested whether periconceptional nutrition with cladodes from the cactus, Opuntia ficus-indica, with or without protein-enrichment, improved the metabolomic profile and reproductive outcomes of adult female sheep. Sixty Rambouillet ewes of similar body weight were randomly allocated among three nutritional treatments that were fed during the breeding period (34 days): Control (Control; n = 20), Opuntia (Opuntia; n = 20) and protein-enriched Opuntia (E-Opuntia; n = 20). There were no effects of treatment on body weight but assessment of urine samples indicated that, for 76 metabolites, the Control and Opuntia groups differed completely (P < 0.05), whereas there was overlap between the Control and E-Opuntia groups. It appears that, in Opuntia-fed and Control-fed sheep, different functional groups are activated leading to changes in the metabolism of glucose, tyrosine, methane, and glycerolipids. Fertility and reproductive rate tended to be higher in the Opuntia (70% and 95%) and E-Opuntia (90% and 110%) groups than in the Control (55% and 65%), and an orthogonal contrast revealed the difference between Control and Opuntia to be significant for both reproductive variables (P < 0.05). We conclude that nutritional supplementation with Opuntia cladodes, with or without protein enrichment, increased fertility rate and reproductive rate of female sheep, without any accompanying increases in body weight. Our observations suggest that the reproductive responses to Opuntia do not simply reflect a response to good nutrition, but might be caused by specific metabolites/metabolomic pathways, perhaps by an activation of the metabolism of glucose, methane, tyrosine and glycerolipids. There are few reports relating these metabolomic compounds with the metabolism of the sheep, let alone with reproductive efficiency. The novelty of these discoveries suggests that we need further research into the mechanisms through which nutrition affects the reproductive system.
Assessing multiple threats to seabird populations using flesh-footed shearwaters Ardenna carneipes on Lord Howe Island, Australia as case study
Authors: Wilcox Chris , Carlile Nicholas , Hardesty Britta Denise , Reid Tim 
Published: March 2021

AbstractGlobally, seabird populations have been in decline due to multiple threats throughout their range. Separating simultaneous pressures is challenging and can require significant amounts of data over long periods of time. We use spatial contrasts to investigate the relative importance of several drivers for the purported decline in a species listed as in decline as an example species, the Flesh-footed shearwater (Ardenna carneipes). On Lord Howe Island in the Tasman Sea, Australia, this seabird suffers from habitat loss due to housing development, intensive mortality in fisheries, plastic ingestion, and roadkill due to vehicular traffic on its breeding island. We repeated a quantitative survey of the population to ascertain whether the decline previously reported had continued and to evaluate the purported mortality sources (Reid et al. in PLoS ONE 8(4):e58230, 2013, Lavers et al. in Global Ecol Conserv 17:e00579, 2019). We measured burrow density, area of occurrence, occupancy and breeding success, integrating them with previous surveys using a Bayesian statistical model to generate longer term estimates of demographic rates. We used spatial patterns to test whether mortality on roads or proximity to human habitation was influencing population demographics. In contrast to predictions, we found the population had stabilised or increased. Characteristics such as burrow occupancy and breeding success showed little pattern, with weak evidence for impacts from road mortality and housing development. Such a data-rich approach is substantially more informative and can better support seabird conservation and management efforts does require more field-time and additional equipment than most contemporary surveys, the data is substantially more informative and can better clarify the results of efforts in seabird conservation and management.
Response of chloroplast pigments, sugars and phenolics of sweet cherry leaves to chilling
Authors: Vosnjak Matej , Sircelj Helena , Hudina Metka , Usenik Valentina 
Published: March 2021

AbstractThe aim of the present study was to evaluate the effect of post-flowering chilling of sweet cherry (Prunus aviumL.) on the content of biochemical parameters in the leaf (chloroplast pigments, sugars and phenolics). The effect of chilling was investigated in two experiments. Potted 2-year-old trees of cv. 'Grace Star' and 'Schneiders' were exposed to one, two or three consecutive overnight chillings at an average air temperature of 4.7 °C (Experiment I), but in the following year only trees of 'Grace Star' were chilled at 2.2 °C (Experiment II), 3 to 7 weeks after flowering. The analysis of the biochemical parameters was performed by high performance liquid chromatography combined with electrospray ionization mass spectrometry. Chilling at 4.7 °C caused little or no stress, while 2.2 °C induced more intense stress with increased zeaxanthin, sugar and phenolic content in leaves, while exposure of trees to higher temperatures and closer to flowering showed no changes. Two or three consecutive overnight chilling periods increased the phenolic content and enhanced the accumulation of zeaxanthin in the leaves. Sucrose, sorbitol, fructose, total sugar, and total flavonoid content in leaves increased within 48 h after chilling. Zeaxanthin epoxidized within 24 h after one and 48 h after one and two consecutive overnight chillings.
Prolonged Positional Downbeat Nystagmus in Benign Paroxysmal Positional Vertigo: A Case Report and Literature Review
Authors: Lee Hyun-Jin , Ahn Seong Ki , Yim Chae Dong , Kim Seong Dong , Hur Dong Gu 
Published: March 2021

Purpose
This study aimed to report an unusual case of benign paroxysmal positional vertigo (BPPV), who showed prolonged positional downbeat nystagmus without latency and was diagnosed with cupulolithiasis of the anterior canal (AC). We compared this case with one of typical AC-BPPV, and possible mechanisms underlying the atypical characteristics were discussed.

Method
Two patients diagnosed with AC-BPPV were reported. Positional testing using video-oculography goggles was performed, and outcomes were measured via medical records and analysis of videos of the nystagmus.

Results
Downbeat nystagmus was observed in the contralateral Dix–Hallpike test in both cases. The torsional component was subtle or absent, but motion was induced toward the affected ear. The two cases differed in latency and duration of vertigo, as well as habituation. The patient with atypical nystagmus showed little or no latency and longer duration. Moreover, there was no habituation on repeated tests. The nystagmus showed several differences from that of typical AC-BPPV.

Conclusions
Based on our case, AC-BPPV may induce various unusual clinical manifestations of nystagmus. Accurate diagnosis requires careful consideration of the patient's symptoms and the characteristics of the nystagmus.

Supplemental Material

https://doi.org/10.23641/asha.14265356
Materials Matter: An Exploration of Text Complexity and Its Effects on Middle School Readers' Comprehension Processing
Authors: Dahl Amanda C. , Carlson Sarah E. , Renken Maggie , McCarthy Kathryn S. , Reynolds Erin 
Published: March 2021

PurposeComplex features of science texts present idiosyncratic challenges for middle grade readers, especially in a post–Common Core educational world where students' learning is dependent on understanding informational text. The primary aim of this study was to explore how middle school readers process science texts and whether such comprehension processes differed due to features of complexity in two science texts.MethodThirty 7th grade students read two science texts with different profiles of text complexity in a think-aloud task. Think-aloud protocols were coded for six comprehension processes: connecting inferences, elaborative inferences, evaluative comments, metacognitive comments, and associations. We analyzed the quantity and type of comprehension processes generated across both texts in order to explore how features of text complexity contributed to the comprehension processes students produced while reading.ResultsStudents made significantly more elaborative and connecting inferences when reading a text with deep cohesion, simple syntax, and concrete words, while students made more evaluative comments, paraphrases, and metacognitive comments when reading a text with referential cohesion, complex syntax, and abstract words.ConclusionsThe current study provides exploratory evidence for features of text complexity affecting the type of comprehension processes middle school readers generate while reading science texts. Accordingly, science classroom texts and materials can be evaluated for word, sentence, and passage features of text complexity in order to encourage deep level comprehension of middle school readers.
Fragmentation and kinematics in high-mass star formation
Authors: Beuther H. , Gieser C. , Suri S. , Linz H. , Klaassen P. , Semenov D. , Winters J. M. , Henning Th. , Soler J. D. , Urquhart J. S. , Syed J. , Feng S. , Möller T. , Beltrán M. T. , Sánchez-Monge Á. , Longmore S. N. , Peters T. , Ballesteros-Paredes J. , Schilke P. , Moscadelli L. , Palau A. , Cesaroni R. , Lumsden S. , Pudritz R. , Wyrowski F. , Kuiper R. , Ahmadi A. 
Published: March 2021

Context. The formation of high-mass star-forming regions from their parental gas cloud and the subsequent fragmentation processes lie at the heart of star formation research.
Aims. We aim to study the dynamical and fragmentation properties at very early evolutionary stages of high-mass star formation.
Methods. Employing the NOrthern Extended Millimeter Array and the IRAM 30 m telescope, we observed two young high-mass star-forming regions, ISOSS22478 and ISOSS23053, in the 1.3 mm continuum and spectral line emission at a high angular resolution (~0.8″).
Results. We resolved 29 cores that are mostly located along filament-like structures. Depending on the temperature assumption, these cores follow a mass-size relation of approximately M ∝ r2.0 ± 0.3, corresponding to constant mean column densities. However, with different temperature assumptions, a steeper mass-size relation up to M ∝ r3.0 ± 0.2, which would be more likely to correspond to constant mean volume densities, cannot be ruled out. The correlation of the core masses with their nearest neighbor separations is consistent with thermal Jeans fragmentation. We found hardly any core separations at the spatial resolution limit, indicating that the data resolve the large-scale fragmentation well. Although the kinematics of the two regions appear very different at first sight – multiple velocity components along filaments in ISOSS22478 versus a steep velocity gradient of more than 50 km s−1 pc−1 in ISOSS23053 – the findings can all be explained within the framework of a dynamical cloud collapse scenario.
Conclusions. While our data are consistent with a dynamical cloud collapse scenario and subsequent thermal Jeans fragmentation, the importance of additional environmental properties, such as the magnetization of the gas or external shocks triggering converging gas flows, is nonetheless not as well constrained and would require future investigation.
The young Adelaide family: Possible sibling to Datura?
Authors: Vokrouhlický D. , Novaković B. , Nesvorný D. 
Published: March 2021

Context.Very young asteroid families may record processes that accompanied their formation in the most pristine way. This makes analysis of this special class particularly interesting.Aims.We studied the very young Adelaide family in the inner part of the main belt. This cluster is extremely close to the previously known Datura family in the space of proper orbital elements and their ages overlap. As a result, we investigated the possibility of a causal relationship between the two families.Methods.We identified Adelaide family members in the up-to-date catalogue of asteroids. By computing their proper orbital elements we inferred the family structure. Backward orbital integration of selected members allowed us to determine the age of the family.Results.The largest fragment (525) Adelaide, an S-type asteroid about 10 km in size, is accompanied by 50 sub-kilometre fragments. This family is a typical example of a cratering event. The very tiny extent in the semi-major axis minimises chances that some significant mean motion resonances influence the dynamics of its members, though we recognise that part of the Adelaide family is affected by weak, three-body resonances. Weak chaos is also produced by distant encounters with Mars. Simultaneous convergence of longitude of node for the orbits of six selected members to that of (525) Adelaide constrains the Adelaide family age to 536 ± 12 kyr (formal solution). While suspiciously overlapping with the age of the Datura family, we find it unlikely that the formation events of the two families are causally linked. In all likelihood, the similarity of their ages is just a coincidence.
Sublimation of ice-dust mixtures in cooled vacuum environments to reproduce cometary morphologies
Authors: Haack David , Lethuillier Anthony , Kreuzig Christopher , Feller Clément , Gundlach Bastian , Pommerol Antoine , Blum Jürgen , Otto Katharina 
Published: March 2021

Aims. The morphology of cometary surfaces can provide important information to constrain the composition and evolution of comets. In this work, we investigate the sublimation behavior of comet analog materials and how the sample composition affects the evolution of morphological features in laboratory experiments. In our experiments, we used dust ice mixtures as analog material to form observed cometary morphologies.
Methods. We used ice-dust mixtures in different mixing ratios as cometary analog material. In order to obtain realistic results, we scaled the expected cohesive and gravitational forces on comets to laboratory conditions. The samples were placed in a vacuum sublimation chamber and permanently cooled down to temperatures below 150 K to simulate the space environment. In the experiment, the samples were insolated with a light source from two different directions and alterations on the surface were recorded with a camera.
Results. We find that the morphology of sublimation residues of ice-dust mixtures is strongly dependent on the ice-dust ratio as well as the insolation direction. High amounts of ice cause constant surface alteration and lead to exotic morphologies. Low amounts cause fewer and more episodic surface changes during its sublimation. Collapse events resulting in irregular and very rough surfaces occur during horizontal insolation.
Chromospheric and coronal heating and jet acceleration due to reconnection driven by flux cancellation
Authors: Syntelis P. , Priest E. R. 
Published: March 2021

Context. Recent observations have shown that magnetic flux cancellation occurs at the photosphere more frequently than previously thought.
Aims. In order to understand the energy release by reconnection driven by flux cancellation, we previously studied a simple model of two cancelling polarities of equal flux. Here, we further develop our analysis to achieve a more general setup where the two cancelling polarities have unequal magnetic fluxes and where many new features are revealed.
Methods. We carried out an analytical study of the cancellation of two magnetic fragments of unequal and opposite flux that approach one another and are located in an overlying horizontal magnetic field.
Results. The energy release as microflares and nanoflares occurs in two main phases. During phase 1a, a separator is formed and reconnection is driven at it as it rises to a maximum height and then moves back down to the photosphere, heating the plasma and accelerating plasma jets in the process. During phase 1b, once the separator moves back to the photosphere, it bifurcates into two null points. Reconnection is no longer driven at the separator and an isolated magnetic domain connecting the two polarities is formed. During phase 2, the polarities cancel out at the photosphere as magnetic flux submerges below the photosphere and as reconnection occurs at and above the photosphere and plasma jets and a mini-filament eruption can be produced.