bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recurrent convolutional neural networks for poet identification
Authors: Salami Dariush , Momtazi Saeedeh 
Published: December 2019

Abstract
Deep neural networks have been widely used in various language processing tasks. Recurrent neural networks (RNNs) and convolutional neural networks (CNN) are two common types of neural networks that have a successful history in capturing temporal and spatial features of texts. By using RNN, we can encode input text to a lower space of semantic features while considering the sequential behavior of words. By using CNN, we can transfer the representation of input text to a flat structure to be used for classifying text. In this article, we proposed a novel recurrent CNN model to capture not only the temporal but also the spatial features of the input poem/verse to be used for poet identification. Considering the shortcomings of the normal RNNs, we try both long short-term memory and gated recurrent unit units in the proposed architecture and apply them to the poet identification task. There are a large number of poems in the history of literature whose poets are unknown. Considering the importance of the task in the information processing field, a great variety of methods from traditional learning models, such as support vector machine and logistic regression, to deep neural network models, such as CNN, have been proposed to address this problem. Our experiments show that the proposed model significantly outperforms the state-of-the-art models for poet identification by receiving either a poem or a single verse as input. In comparison to the state-of-the-art CNN model, we achieved 9% and 4% improvements in f-measure for poem- and verse-based tasks, respectively.
The role of psychologists in international migration research: Complementing other expertise and an interdisciplinary way forward
Authors: Schwartz Seth J , Walsh Sophie D , Ward Colleen , Tartakovsky Eugene , Weisskirch Robert S , Vedder Paul , Makarova Elena , Bardi Anat , Birman Dina , Oppedal Brit , Benish-Weisman Maya , Lorenzo-Blanco Elma I , Güngör Derya , Stevens Gonneke W J M , Benet-Martínez Veronica , Titzmann Peter F , Silbereisen Rainer K , Geeraert Nicolas ,   the Psychology of Migration Working Group
Published: December 2019

AbstractThis research note addresses the current and potential future role of psychologists in the study of international migration. We review ways in which psychologists have contributed to the study of migration, as well as ways in which psychological scholarship could be integrated with work from other social science fields. Broadly, we discuss four major contributions that psychology brings to the study of international migration—studying migrants’ internal psychological experiences, incorporating a developmental perspective, conducting experimental studies, and integrating across levels of analysis. Given the position of psychology as a ‘hub science’ connecting more traditional social sciences with health and medical sciences, we argue for a more prominent role for psychologists within the study of international migration. Such a role is intended to complement the roles of other social scientists and to create a more interdisciplinary way forward for the field of migration studies. The research note concludes with an agenda for further scholarship on migration.
The first observed stellar occultations by the irregular satellite Phoebe (Saturn IX) and improved rotational period
Authors: Gomes-Júnior A R , Assafin M , Braga-Ribas F , Benedetti-Rossi G , Morgado B E , Camargo J I B , Vieira-Martins R , Desmars J , Sicardy B , Barry T , Campbell-White J , Fernández-Lajús E , Giles D , Hanna W , Hayamizu T , Hirose T , De Horta A , Horvat R , Hosoi K , Jehin E , Kerr S , Machado D I , Mammana L A , Maybour D , Owada M , Rahvar S , Snodgrass C 
Published: December 2019

ABSTRACT
We report six stellar occultations by Phoebe (Saturn IX), an irregular satellite of Saturn, obtained between mid-2017 and mid-2019. The 2017 July 6 event was the first stellar occultation by an irregular satellite ever observed. The occultation chords were compared to a 3D shape model of the satellite obtained from Cassini observations. The rotation period available in the literature led to a sub-observer point at the moment of the observed occultations where the chords could not fit the 3D model. A procedure was developed to identify the correct sub-observer longitude. It allowed us to obtain the rotation period with improved precision compared to the currently known value from literature. We show that the difference between the observed and the predicted sub-observer longitude suggests two possible solutions for the rotation period. By comparing these values with recently observed rotational light curves and single-chord stellar occultations, we can identify the best solution for Phoebe’s rotational period as 9.27365 ± 0.00002 h. From the stellar occultations, we also obtained six geocentric astrometric positions in the ICRS as realized by the Gaia DR2 with uncertainties at the 1-mas level.
The frequency of very young galaxies in the local Universe – II. The view from SDSS spectra
Authors: Mamon Gary A , Trevisan Marina , Thuan Trinh X , Gallazzi Anna , Davé Romeel 
Published: December 2019

ABSTRACT
Only a handful of galaxies in the local Universe appear to be very young. We estimate the fraction of very young galaxies (VYGs), defined as those with more than half their stellar masses formed within the last Gyr. We fit non-parametric star formation histories (SFHs) to ∼280 000 galaxy spectra from a flux- and volume-limited subsample of the Main Galaxy Sample (MGS) of the SDSS, which is also complete in mass-to-light ratio, thus properly accounting for passive galaxies of a given mass. The VYG fractions decrease with increasing galaxy stellar mass, from ∼50 per cent at $m = 10^8\, {\rm M}_{\odot }$ to ∼0.1 per cent at $m = 10^{11.5}\, {\rm M}_{\odot }$, with differences of up to 1 dex between the different spectral models used to estimate the SFH and on how we treat aperture effects. But old stellar populations may hide in our VYGs despite our conservative VYG sample built with galaxies that are globally bluer than within the region viewed by the SDSS fibre. The VYG fractions versus mass decrease more gradually compared to the Tweed et al. predictions using analytical and semi-analytical models of galaxy formation, but agree better with the SIMBA hydrodynamical simulation. These discrepancies highlight the usefulness of VYGs in constraining the strong uncertainties in both galaxy formation models and spectral modelling of galaxy SFHs. Given the lognormal cosmic SFH, these mean VYG fractions suggest that galaxies above $10^8\, \rm M_\odot$ undergo at most four major starbursts on average.
SILCC-Zoom: H2 and CO-dark gas in molecular clouds – the impact of feedback and magnetic fields
Authors: Seifried D , Haid S , Walch S , Borchert E M A , Bisbas T G 
Published: December 2019

ABSTRACT
We analyse the CO-dark molecular gas content of simulated molecular clouds from the SILCC-Zoom project. The simulations reach a resolution of 0.1 pc and include H2 and CO formation, radiative stellar feedback and magnetic fields. CO-dark gas is found in regions with local visual extinctions $A_\rm {V, 3D} \sim$ 0.2–1.5, number densities of 10–103 cm−3 and gas temperatures of few 10–100 K. CO-bright gas is found at number densities above 300 cm−3 and temperatures below 50 K. The CO-dark gas fractions range from 40 per cent to 95 per cent and scale inversely with the amount of well-shielded gas ($A_\rm {V, 3D}$ ≳ 1.5), which is smaller in magnetized molecular clouds. We show that the density, chemical abundances and $A_\rm {V, 3D}$ along a given line-of-sight cannot be properly determined from projected quantities. As an example, pixels with a projected visual extinction of $A_\rm {V, 2D} \simeq$ 2.5–5 can be both, CO-bright or CO-dark, which can be attributed to the presence or absence of strong density enhancements along the line-of-sight. By producing synthetic CO(1-0) emission maps of the simulations with RADMC-3D, we show that about 15–65 per cent of the H2 is in regions with intensities below the detection limit. Our clouds have $X_\rm {CO}$-factors around 1.5 × 1020 cm−2 (K km s−1)−1 with a spread of up to a factor ∼ 4, implying a similar uncertainty in the derived total H2 masses and even worse for individual pixels. Based on our results, we suggest a new approach to determine the H2 mass, which relies on the availability of CO(1-0) emission and $A_\rm {V, 2D}$ maps. It reduces the uncertainty of the clouds’ overall H2 mass to a factor of ≲ 1.8 and for individual pixels, i.e. on sub-pc scales, to a factor of ≲ 3.
Parallel Seed Color Adaptation during Multiple Domestication Attempts of an Ancient New World Grain
Authors: Stetter Markus G , Vidal-Villarejo Mireia , Schmid Karl J 
Published: December 2019

AbstractThousands of plants have been selected as crops; yet, only a few are fully domesticated. The lack of adaptation to agroecological environments of many crop plants with few characteristic domestication traits potentially has genetic causes. Here, we investigate the incomplete domestication of an ancient grain from the Americas, amaranth. Although three grain amaranth species have been cultivated as crop for millennia, all three lack key domestication traits. We sequenced 121 crop and wild individuals to investigate the genomic signature of repeated incomplete adaptation. Our analysis shows that grain amaranth has been domesticated three times from a single wild ancestor. One trait that has been selected during domestication in all three grain species is the seed color, which changed from dark seeds to white seeds. We were able to map the genetic control of the seed color adaptation to two genomic regions on chromosomes 3 and 9, employing three independent mapping populations. Within the locus on chromosome 9, we identify an MYB-like transcription factor gene, a known regulator for seed color variation in other plant species. We identify a soft selective sweep in this genomic region in one of the crop species but not in the other two species. The demographic analysis of wild and domesticated amaranths revealed a population bottleneck predating the domestication of grain amaranth. Our results indicate that a reduced level of ancestral genetic variation did not prevent the selection of traits with a simple genetic architecture but may have limited the adaptation of complex domestication traits.
Polygenic Patterns of Adaptive Introgression in Modern Humans Are Mainly Shaped by Response to Pathogens
Authors: Gouy Alexandre , Excoffier Laurent 
Published: December 2019

AbstractAnatomically modern humans carry many introgressed variants from other hominins in their genomes. Some of them affect their phenotype and can thus be negatively or positively selected. Several individual genes have been proposed to be the subject of adaptive introgression, but the possibility of polygenic adaptive introgression has not been extensively investigated yet. In this study, we analyze archaic introgression maps with refined functional enrichment methods to find signals of polygenic adaptation of introgressed variants. We first apply a method to detect sets of connected genes (subnetworks) within biological pathways that present higher-than-expected levels of archaic introgression. We then introduce and apply a new statistical test to distinguish between epistatic and independent selection in gene sets of present-day humans. We identify several known targets of adaptive introgression, and we show that they belong to larger networks of introgressed genes. After correction for genetic linkage, we find that signals of polygenic adaptation are mostly explained by independent and potentially sequential selection episodes. However, we also find some gene sets where introgressed variants present significant signals of epistatic selection. Our results confirm that archaic introgression has facilitated local adaptation, especially in immunity related and metabolic functions and highlight its involvement in a coordinated response to pathogens out of Africa.
Dynamics of DNA nicking and unwinding by the RepC–PcrA complex
Authors: Carrasco Carolina , Pastrana Cesar L , Aicart-Ramos Clara , Leuba Sanford H , Khan Saleem A , Moreno-Herrero Fernando 
Published: December 2019

AbstractThe rolling-circle replication is the most common mechanism for the replication of small plasmids carrying antibiotic resistance genes in Gram-positive bacteria. It is initiated by the binding and nicking of double-stranded origin of replication by a replication initiator protein (Rep). Duplex unwinding is then performed by the PcrA helicase, whose processivity is critically promoted by its interaction with Rep. How Rep and PcrA proteins interact to nick and unwind the duplex is not fully understood. Here, we have used magnetic tweezers to monitor PcrA helicase unwinding and its relationship with the nicking activity of Staphylococcus aureus plasmid pT181 initiator RepC. Our results indicate that PcrA is a highly processive helicase prone to stochastic pausing, resulting in average translocation rates of 30 bp s−1, while a typical velocity of 50 bp s−1 is found in the absence of pausing. Single-strand DNA binding protein did not affect PcrA translocation velocity but slightly increased its processivity. Analysis of the degree of DNA supercoiling required for RepC nicking, and the time between RepC nicking and DNA unwinding, suggests that RepC and PcrA form a protein complex on the DNA binding site before nicking. A comprehensive model that rationalizes these findings is presented.
Is Youth Football Safe? An Analysis of Youth Football Head Impact Data
Authors: Heary Robert F , Majmundar Neil , Nagurka Roxanne 
Published: December 2019

Abstract

BACKGROUND
The issue of whether sports-related head trauma at the youth level can result in long-term sequelae that may negatively impact the participant has been widely debated.

OBJECTIVE
To investigate head impacts in the Summit Youth Football League equipped with helmets using the Riddell InSite impact monitoring system. The monitoring system allowed for analysis of the number of impacts and severity of impacts by player.

METHODS
Data were obtained for all 20 members of the youth football team. Impacts were recorded as “low,” “medium,” and “high” intensity.

RESULTS
All 20 players participated in all practices and games throughout the season. No player suffered a concussion throughout the entire season. There were 817 recorded impacts throughout the season. This was an average of 41 impacts per player over the course of the season and fewer than 4 impacts per player per week. Only one impact registered as “high.”

CONCLUSION
We demonstrate that there are few head impacts over the course of an entire season at the middle school level. Guardian Caps, safe tackling techniques, and the age of participants may have contributed to the very low number of impacts recorded and the complete lack of injuries. This study only provides data demonstrating that youth football, when Guardian Caps and safe tackling techniques are enforced, does not appear to result in significant head impacts causing immediate head injuries. This study cannot comment on the safety of playing football at the collegiate or professional level.
Convergent genomic signatures of high-altitude adaptation among domestic mammals
Authors: Wu Dong-Dong , Yang Cui-Ping , Wang Ming-Shan , Dong Kun-Zhe , Yan Da-Wei , Hao Zi-Qian , Fan Song-Qing , Chu Shu-Zhou , Shen Qiu-Shuo , Jiang Li-Ping , Li Yan , Zeng Lin , Liu He-Qun , Xie Hai-Bing , Ma Yun-Fei , Kong Xiao-Yan , Yang Shu-Li , Dong Xin-Xing , Esmailizadeh Ali , Irwin David M , Xiao Xiao , Li Ming , Dong Yang , Wang Wen , Shi Peng , Li Hai-Peng , Ma Yue-Hui , Gou Xiao , Chen Yong-Bin , Zhang Ya-Ping 
Published: December 2019

Abstract
Abundant and diverse domestic mammals living on the Tibetan Plateau provide useful materials for investigating adaptive evolution and genetic convergence. Here, we used 327 genomes from horses, sheep, goats, cattle, pigs and dogs living at both high and low altitudes, including 73 genomes generated for this study, to disentangle the genetic mechanisms underlying local adaptation of domestic mammals. Although molecular convergence is comparatively rare at the DNA sequence level, we found convergent signature of positive selection at the gene level, particularly the EPAS1 gene in these Tibetan domestic mammals. We also reported a potential function in response to hypoxia for the gene C10orf67, which underwent positive selection in three of the domestic mammals. Our data provide an insight into adaptive evolution of high-altitude domestic mammals, and should facilitate the search for additional novel genes involved in the hypoxia response pathway.
White matter tract-specific alterations in male patients with untreated obstructive sleep apnea are associated with worse cognitive function
Authors: Koo Dae Lim , Kim Hye Ryun , Kim Hosung , Seong Joon-Kyung , Joo Eun Yeon 
Published: December 2019

Abstract

Study Objectives
Neurocognitive impairment is one of the daytime symptoms of obstructive sleep apnea (OSA). We proposed to use tract-specific statistical analysis (TSSA) to investigate whether there are fiber tract abnormalities in OSA, which may be undiscovered using voxel-based approaches, and whether such tract-specific disruptions in brain connectivity are associated with neuropsychological deficits in patients with untreated OSA.

Methods
We enrolled 38 patients with OSA diagnosed by overnight polysomnography, and 41 healthy sleepers. Fractional anisotropy (FA) and mean diffusivity (MD) maps were obtained from whole-brain diffusion tensor imaging, and TSSA were used to assess regional deficits of white matter tracts. All participants underwent a battery of neuropsychological tests. To evaluate the association between FA values and clinical, polysomnographic, and neuropsychological parameters in the OSA group, permutation-based tests for correlation were performed preceding cluster-based statistics.

Results
Compared to healthy controls, patients with OSA showed decreased values of FA in the left and right anterior thalamic radiations, and right uncinate fasciculus (UNC) (p &lt; 0.001, p = 0.005, and p = 0.008, respectively). A lower score of digit span backward was associated with lower FA values of right UNC in the OSA group (p = 0.023). The Rey Complex Figure Test copy score revealed a positive correlation with FA values in the right UNC (p = 0.010).

Conclusions
The TSSA method indeed identified previously unrevealed tract-specific disruptions in OSA. Furthermore, reduced FA values in the frontal lobe portion of the right UNC which has been known to be involved in working memory function were significantly associated with lower cognitive performance in patients with untreated OSA.
Characteristics and Outcomes of Autoimmune Hepatitis from a Tertiary Paediatric Centre, Cape Town, South Africa
Authors: Yassin Sawsan , De Lacy Ronalda , Pillay Komala , Goddard Elizabeth 
Published: December 2019

Abstract

Objectives
To describe the clinical characteristics, biochemical and histological features, outcomes and predictors of prognosis of children with autoimmune hepatitis (AIH) from a paediatric centre in South Africa.

Methods
Thirty-nine children diagnosed with AIH at Red Cross War Memorial Children’s Hospital between 2005 and 2015 were included. Relevant patient’s data were retrieved from the hospital’s medical records and database. Liver biopsy slides were reviewed. Ethical approval was obtained. Data were analysed using SPSS.

Results
Females were 29 (74%). Mean age at presentation was 7.27 ± 3.35 years and the mean follow-up was 4.5 ± 2.4 years. Jaundice was present in 97% of patients at presentation. An acute presentation was observed in 26 (67%) even though cirrhosis was detected in 22 (56%). Autoantibody screening was completed in 35 patients, 20 (57%) were AIH-1, 1 (3%) was AIH-2 and 14 (40%) were seronegative AIH. Of the 25 patients who underwent magnetic resonance cholangiography 17 (68%) had associated autoimmune sclerosing cholangitis. The remission rate was 79%. However, 11 children relapsed later. One child required liver transplantation and one demised. Seronegative and seropositive patients have comparable characteristics and outcomes. While a higher alanine transaminase (ALT) level at presentation is a significant predictor of remission, a lower ALT level and cirrhosis are significant risk factors for unfavourable outcome. Overall survival rate was 97%.

Conclusion
AIH responds well to therapy with excellent survival. Hence, it should be considered in any child presenting with viral screen negative hepatitis and start therapy timeously to prevent disease progression.
CORRELATION BETWEEN POSTERIOR STAPHYLOMA AND DOME-SHAPED MACULA IN HIGH MYOPIC EYES
Authors: Dai Fangfang , Li Shuyin , Wang Yanting , Li Shuangshuang , Han Jinfeng , Li Mengdi , Zhang Zhong , Jin Xuemin , Dou Shewei 
Published: December 2019

Purpose:
To investigate the relationship between posterior staphyloma and dome-shaped macula (DSM) in highly myopic eyes.

Methods:
The clinical data were collected from patients with high myopia: diopter, best-corrected visual acuity, axial length, fundus images, optical coherence tomography, and 3D magnetic resonance imaging. A DSM was defined as a convex curvature of the macula in one or both of the vertical and horizontal optical coherence tomography scans. The relationship between DSM and posterior staphyloma was evaluated.

Results:
A total of 123 eyes were included. Dome-shaped macula was found in 18 eyes (14.63%). Twelve eyes with DSM had positive 3D magnetic resonance imaging findings. Nine eyes had horizontal oval-shaped dome, and a band-shaped inward convexity that extended horizontally from the optic disc through the fovea could be seen. Three eyes had round dome, and 3D magnetic resonance imaging showed a round inward convexity of the macular area. Five inward convexities were the border of multiple staphylomas, five were the boundary of one staphyloma, and two were within a single staphyloma.

Conclusion:
The formation of highly myopic DSM is related to the morphological change of the entire posterior segment.