bluuebunny/crossref_metadata_2025_split huggingface dataset:
Circumstellar CO J = 3→2 detected around the evolving metal-poor ([Fe/H] ≈ −1.15 dex) AGB star RU Vulpeculae
Authors: McDonald I , Uttenthaler S , Zijlstra A A , Richards A M S , Lagadec E 
Published: October 2019

ABSTRACT
We report the first detection of CO J = 3→2 around a truly metal-poor evolved star. RU Vulpeculae is modelled to have Teff ≈ 3620 K, L ≈ 3128 ± 516 L⊙, log(g) = 0.0 ± 0.2 dex and [Fe/H] = −1.3 to −1.0 dex, and is modelled to have recently undergone a thermal pulse. Its infrared flux has approximately doubled over 35 yr. ALMA observations show the 3→2 line is narrow (half-width ∼1.8–3.5 km s−1). The 2→1 line is much weaker: it is not confidently detected. Spectral-energy-distribution fitting indicates very little circumstellar absorption, despite its substantial mid-infrared emission. A VISIR mid-infrared spectrum shows features typical of previously observed metal-poor stars, dominated by a substantial infrared excess but with weak silicate and (possibly) Al2O3 emission. A lack of resolved emission, combined with weak 2→1 emission, indicates the dense circumstellar material is truncated at large radii. We suggest that rapid dust condensation is occurring, but with an aspherical geometry (e.g. a disc or clumps) that does not obscure the star. We compare with T UMi, a similar star which is currently losing its dust.
Radio Interferometric Calibration Using a Complex Student’s t-distribution and Wirtinger Derivatives
Authors: Sob U M , Bester H L , Smirnov O M , Kenyon J S , Grobler T L 
Published: October 2019

Abstract
Radio interferometric gain calibration can be biased by incomplete sky models and radio frequency interference, resulting in calibration artefacts that can restrict the dynamic range of the resulting images. It has been suggested that calibration algorithms employing heavy-tailed likelihood functions are less susceptible to this due to their robustness against outliers in the data. We present an algorithm based on a Student’s t-distribution which leverages the framework of complex optimisation and Wirtinger calculus for efficient and robust interferometric gain calibration. We integrate this algorithm as an option in the newly released calibration software package, CubiCal. We demonstrate that the algorithm can mitigate some of the biases introduced by incomplete sky models and radio frequency interference by applying it to both simulated and real data. Our results show significant improvements compared to a conventional least-squares solver which assumes a Gaussian likelihood function. Furthermore, we provide some insight into why the algorithm outperforms the conventional solver, and discuss specific scenarios (for both direction-independent and direction-dependent self-calibration) where this is expected to be the case.
The very slow rotation of the magnetic O9.7 V star HD 54879
Authors: Hubrig S , Järvinen S P , Schöller M , Hummel C A 
Published: October 2019

ABSTRACT
The first FOcal Reducer low dispersion Spectrograph (FORS 2) spectropolarimetric observation of the longitudinal magnetic field of HD 54879 of the order of −600 G with a lower limit of the dipole strength of ∼2 kG dates back to 2014. Since then, observations showed a gradual decrease of the absolute value of the mean longitudinal magnetic field. In the course of the most recent monitoring of HD 54879 using FORS 2 spectropolarimetric observations from 2017 October to 2018 February, a longitudinal magnetic field strength change from about −300 G down to about −90 G was reported. A sudden increase of the absolute value of the mean longitudinal magnetic field and an accompanying spectral variability was detected on 2018 February 17. New FORS 2 spectropolarimetric data obtained from 2018 December to 2019 February confirm the very slow magnetic field variability, with the field decreasing from about 150 G to −100 G over 2 months. Such a slow magnetic field variability, related to the extremely slow rotation of HD 54879, is also confirmed using high-resolution High Accuracy Radial velocity Planet Searcher in polarimetric mode and Echelle SpectroPolarimetric Device for the Observation of Stars spectropolarimetry. The re-analysis of the FORS 2 polarimetric spectra from 2018 February indicates that the previously reported field increase and the change of the spectral appearance was caused by improper spectra extraction and wavelength calibration using observations obtained at an insufficient signal-to-noise ratio. The presented properties of HD 54879 are discussed in the context of the Of?p spectral classification.
Development of a simulator of the SIMBIOSYS suite onboard the BepiColombo mission
Authors: Slemer A , Zusi M , Simioni E , Da Deppo V , Re C , Lucchetti A , Della Corte V , Filacchione G , Palumbo P , Capaccioni F , Capria M T , Amoroso M , Mugnuolo R , Cremonese G 
Published: October 2019

ABSTRACT
BepiColombo is the fifth cornerstone mission of the European Space Agency (ESA) dedicated to study the Mercury planet. The BepiColombo spacecraft comprises two science modules: the Mercury Planetary Orbiter (MPO) realized by ESA and the Mercury Magnetospheric Orbiter provided by the Japan Aerospace Exploration Agency. The MPO is composed by 11 instruments, including the ‘Spectrometer and Imagers for MPO BepiColombo Integrated Observatory System’ (SIMBIOSYS). The SIMBIOSYS suite includes three optical channels: a Stereoscopic Imaging Channel, a High Resolution Imaging Channel, and a Visible and near Infrared Hyperspectral Imager. SIMBIOSYS will characterize the hermean surface in terms of surface morphology, volcanism, global tectonics, and chemical composition. The aim of this work is to describe a tool for the radiometric response prediction of the three SIMBIOSYS channels. Given the spectral properties of the surface, the instrument characteristics, and the geometrical conditions of the observation, the realized SIMBIOSYS simulator is capable of estimating the expected signal and integration times for the entire mission lifetime. In the simulator the spectral radiance entering the instrument optical apertures has been modelled using a Hapke reflectance model implementing the parameters expected for the hermean surface. The instrument performances are simulated by means of calibrated optical and detectors responses. The simulator employs the SPICE (Spacecraft, Planet, Instrument, C-matrix, Environment) toolkit software, which allows us to know for each epoch the exact position of the MPO with respect to the planet surface and the Sun.
Magneto-hydrodynamical origin of eclipsing time variations in post-common-envelope binaries for solar mass secondaries
Authors: Navarrete Felipe H , Schleicher Dominik R G , Käpylä Petri J , Schober Jennifer , Völschow Marcel , Mennickent Ronald E 
Published: October 2019

Abstract
Eclipsing time variations have been observed for a wide range of binary systems, including post-common-envelope binaries. A frequently proposed explanation, apart from the possibility of having a third body, is the effect of magnetic activity, which may alter the internal structure of the secondary star, particularly its quadrupole moment, and thereby cause quasi-periodic oscillations. Here we present two compressible non-ideal magneto-hydrodynamical (MHD) simulations of the magnetic dynamo in a solar mass star, one of them with three times the solar rotation rate (“slow rotator”), the other one with twenty times the solar rotation rate (“rapid rotator”), to account for the high rotational velocities in close binary systems. For the slow rotator, we find that both the magnetic field and the stellar quadrupole moment change in a quasi-periodic manner, leading to O-C (observed - corrected times of the eclipse) variations of ∼0.025 s. For the rapid rotator, the behavior of the magnetic field as well as the quadrupole moment changes become considerably more complex, due to the less coherent dynamo solution. The resulting O-C variations are of the order 0.13 s. The observed system V471 Tau shows two modes of eclipsing time variations, with amplitudes of 151 s and 20 s, respectively. However, the current simulations may not capture all relevant effects due to the neglect of the centrifugal force and self-gravity. Considering the model limitations and that the rotation of V471 Tau is still a factor of 2.5 faster than our rapid rotator, it may be conceivable to reach the observed magnitudes.
Molecular Diversification of the Seminal Fluid Proteome in a Recently Diverged Passerine Species Pair
Authors: Rowe Melissah , Whittington Emma , Borziak Kirill , Ravinet Mark , Eroukhmanoff Fabrice , Sætre Glenn-Peter , Dorus Steve 
Published: October 2019

Abstract
Seminal fluid proteins (SFPs) mediate an array of postmating reproductive processes that influence fertilization and fertility. As such, it is widely held that SFPs may contribute to postmating, prezygotic reproductive barriers between closely related taxa. We investigated seminal fluid (SF) diversification in a recently diverged passerine species pair (Passer domesticus and Passer hispaniolensis) using a combination of proteomic and comparative evolutionary genomic approaches. First, we characterized and compared the SF proteome of the two species, revealing consistencies with known aspects of SFP biology and function in other taxa, including the presence and diversification of proteins involved in immunity and sperm maturation. Second, using whole-genome resequencing data, we assessed patterns of genomic differentiation between house and Spanish sparrows. These analyses detected divergent selection on immunity-related SF genes and positive selective sweeps in regions containing a number of SF genes that also exhibited protein abundance diversification between species. Finally, we analyzed the molecular evolution of SFPs across 11 passerine species and found a significantly higher rate of positive selection in SFPs compared with the rest of the genome, as well as significant enrichments for functional pathways related to immunity in the set of positively selected SF genes. Our results suggest that selection on immunity pathways is an important determinant of passerine SF composition and evolution. Assessing the role of immunity genes in speciation in other recently diverged taxa should be prioritized given the potential role for immunity-related proteins in reproductive incompatibilities in Passer sparrows.
Transcriptomic profiling of trophoblast fusion using BeWo and JEG-3 cell lines
Authors: Msheik H , El Hayek S , Bari M Furqan , Azar J , Abou-Kheir W , Kobeissy F , Vatish M , Daoud G 
Published: October 2019

AbstractIn human placenta, alteration in trophoblast differentiation has a major impact on placental maintenance and integrity. However, little is known about the mechanisms that control cytotrophoblast fusion. The BeWo cell line is used to study placental function, since it forms syncytium and secretes hormones after treatment with cAMP or forskolin. In contrast, the JEG-3 cell line fails to undergo substantial fusion. Therefore, BeWo and JEG-3 cells were used to identify a set of genes responsible for trophoblast fusion. Cells were treated with forskolin for 48 h to induce fusion. RNA was extracted, hybridised to Affymetrix HuGene ST1.0 arrays and analysed using system biology. Trophoblast differentiation was evaluated by real-time PCR and immunocytochemistry analysis. Moreover, some of the identified genes were validated by real-time PCR and their functional capacity was demonstrated by western blot using phospho-specific antibodies and CRISPR/cas9 knockdown experiments. Our results identified a list of 32 altered genes in fused BeWo cells compared to JEG-3 cells after forskolin treatment. Among these genes, four were validated by RT-PCR, including salt-inducible kinase 1 (SIK1) gene which is specifically upregulated in BeWo cells upon fusion and activated after 2 min with forskolin. Moreover, silencing of SIK1 completely abolished the fusion. Finally, SIK1 was shown to be at the center of many biological and functional processes, suggesting that it might play a role in trophoblast differentiation. In conclusion, this study identified new target genes implicated in trophoblast fusion. More studies are required to investigate the role of these genes in some placental pathology.
IPD-IMGT/HLA Database
Authors: Robinson James , Barker Dominic J , Georgiou Xenia , Cooper Michael A , Flicek Paul , Marsh Steven G E 
Published: October 2019

AbstractThe IPD-IMGT/HLA Database, http://www.ebi.ac.uk/ipd/imgt/hla/, currently contains over 25 000 allele sequence for 45 genes, which are located within the Major Histocompatibility Complex (MHC) of the human genome. This region is the most polymorphic region of the human genome, and the levels of polymorphism seen exceed most other genes. Some of the genes have several thousand variants and are now termed hyperpolymorphic, rather than just simply polymorphic. The IPD-IMGT/HLA Database has provided a stable, highly accessible, user-friendly repository for this information, providing the scientific and medical community access to the many variant sequences of this gene system, that are critical for the successful outcome of transplantation. The number of currently known variants, and dramatic increase in the number of new variants being identified has necessitated a dedicated resource with custom tools for curation and publication. The challenge for the database is to continue to provide a highly curated database of sequence variants, while supporting the increased number of submissions and complexity of sequences. In order to do this, traditional methods of accessing and presenting data will be challenged, and new methods will need to be utilized to keep pace with new discoveries.
Predictors of Complications, Functional Outcome, and Morbidity in a Large Cohort Treated With Flow Diversion
Authors: Sweid Ahmad , Starke Robert M , Herial Nabeel , Chalouhi Nohra , Das Somnath , Baldassari Michael P , Alexander Tyler D , Tjoumakaris Stavropoula , Gooch M Reid , Hasan David , Rosenwasser Robert H , Romo Victor , Jabbour Pascal 
Published: October 2019

Abstract

BACKGROUND
A dramatic improvement in obliteration rates of large, wide-necked aneurysms has been observed after the FDA approved the Pipeline Embolization Device (PED) in 2011.

OBJECTIVE
To assess the predictors of complications, morbidity, and unfavorable outcomes in a large cohort of patients with aneurysms treated with PED.

METHODS
A retrospective chart review of a prospectively maintained database for subjects treated with flow diversion from 2010 to 2019.

RESULTS
A total of 598 aneurysms were treated during a period extending from 2010 to 2019 (84.28% females, mean age 55.5 yr, average aneurysm size 8.49 mm). Morbidity occurred at a rate of 5.8% and mortality at a rate of 2.2%. Ischemic stroke occurred at a rate of 3%, delayed aneurysmal rupture (DAR) at 1.2%, and distal intraparenchymal hemorrhage (DIPH) at 1.5%. On multivariate analysis, the predictor of stroke was aneurysm size >15 mm. Predictors of DAR were previous subarachnoid hemorrhage (SAH), increasing aneurysm size, and posterior circulation aneurysm. Predictors of DIPH were using more than 1 PED and baseline P2Y12 value. Predictors of in-stent stenosis were the increasing year of treatment and balloon angioplasty, whereas increasing age and previous treatment were negatively associated with in-stent stenosis. Predictors of morbidity were posterior circulation aneurysms, increasing aneurysm size, and hypertension, and incidental aneurysm diagnosis was protective for morbidity.

CONCLUSION
Flow diversion is a safe and effective treatment option for aneurysms. A better understanding of predictive factors of complications, morbidity, and functional outcomes is of high importance for a more accurate risk assessment.
Comparing Effects of Treatment: Controlling for Confounding
Authors: Yan Han , Karmur Brij S , Kulkarni Abhaya V 
Published: October 2019

Abstract

BACKGROUND
Determining true causal links between an intervention and an outcome forms an imperative task in research studies in neurosurgery. Although the study results sometimes demonstrate clear statistical associations, it is important to ensure that this represents a true causal link. A confounding variable, or confounder, affects the association between a potential predictor and an outcome.

OBJECTIVE
To discuss what confounding is and the means by which it can be eliminated or controlled.

METHODS
We identified neurosurgical research studies demonstrating the principles of eliminating confounding by means of study design and data analysis.

RESULTS
In this report, we outline the role of confounding in neurosurgical studies after giving an overview of its identification. We report on the definition of confounding and effect modification, and the differences in the 2. We explain study design techniques to eliminate confounding, including simple, block, stratified, and minimization randomization, along with restriction of sample and matching. Data analysis techniques of eliminating confounding include regression analysis, propensity scoring, and subgroup analysis.

CONCLUSION
Understanding confounding is important for conducting a good research study. Study design techniques provide the best way to control for confounders, but when not possible to alter study design, data analysis techniques can also provide an effective control.
Time-Varying Risk Premium and Unemployment Risk across Age Groups
Authors: Mitra Indrajit , Xu Yu 
Published: October 2019

AbstractWe show that time-varying risk premium in financial markets can explain a key, yet puzzling, feature of labor markets: the large differences in unemployment risk across worker age groups over the business cycle. Our search model features a time-varying risk premium and learning about unobserved heterogeneity in worker productivity. Their interaction generates large real effects through firms’ labor policies. Our model predicts higher unemployment risk of younger workers relative to prime-age workers when risk premium is high, and the employment ratio of prime-age to young workers to be more cyclical in high beta industries. We find empirical support for these predictions.Authors have furnished an Internet Appendix, which is available on the Oxford University Press Web site next to the link to the final published paper online.
Choosing the right home: settlement responses by larvae of six sea urchin species align with hydrodynamic traits of their contrasting adult habitats
Authors: Hodin Jason , Ferner Matthew C , Gaylord Brian 
Published: October 2019

AbstractOcean organisms as diverse as seaweeds and sea cucumbers exhibit life cycles in which dispersal occurs primarily via microscopic larvae or spores, with adults exhibiting limited or even no dispersal. In benthic animals, the larval stage concludes with irreversible settlement into the benthos. The decision of where and when to settle is thus one of substantial import. Prior work has shown that settlement in two shoreline echinoids (a sea urchin and a sand dollar) is unexpectedly sensitive to an environmental feature (intense fluid turbulence) that can be considered as a signal to larvae of their arrival in the neighbourhood of the hydrodynamically energetic habitats in which these taxa live as adults. Here, we used a comparative approach to explore the evolution of turbulence responsiveness in late-stage echinoid larvae. We examined three pairs of closely related sea urchins that differ in the energetic exposure of their adult habitats and found that larval responsiveness to turbulence was more pronounced in urchins that settle in more hydrodynamically exposed locations. These results raise the possibility that evolutionary differences in larval responsiveness to environmental indicators of appropriate adult habitat might reinforce or even provide a mechanism for vicariance in the ocean.
Mild Traumatic Brain Injury Disrupts Functional Dynamic Attractors of Healthy Mental States
Authors: Vergara Victor M. , van der Horn Harm J. , Mayer Andrew R. , Espinoza Flor A. , van der Naalt Joukje , Calhoun Vince D 
Published: October 2019

AbstractThe human brain has the ability of changing its wiring configuration by increasing or decreasing functional connectivity strength between specific areas. Variable but recurring configuration patterns in dynamic functional connectivity have been observed during resting fMRI experiments, patterns which are defined as dynamic brain states. The question arises whether in a regular healthy brain these states evolve in a random fashion or in a specific sequential order. The current work reveals both the specific state sequence in healthy brains, as well as the set of disruptions in this sequence produced by traumatic brain injury. The healthy sequence consists of oscillatory dynamic connectivity patterns that orbit an attractor state in a high dimensional space. Using discovery (96 subjects) and replication (74 subjects) cohorts, this study demonstrated that mild traumatic brain injury results in immediate orbital disruptions that recover over time. Brain dynamics enter a status of disrupted orbits right after injury, with partial recovery at 4 weeks, and full recovery at 3 months post-injury. In summary, our results describe an aspect of neuronal dysfunction in mild traumatic brain injury that is fully based on brain state dynamics, and different from traditional brain connectivity strength measures.
Operationalizing Occupational Fatigue in Pharmacists: An Exploratory Factor Analysis
Authors: Watterson Taylor , Look Kevin , Steege Linsey , Chui Michelle 
Published: October 2019

IntroductionThe Quadruple Aim recognizes that caring for the healthcare employee is necessary to optimize patient outcomes and health system performance. Although previous research has assessed pharmacists’ workload, this study is the first to describe pharmacist occupational fatigue – a characteristic of excessive workload that inhibits workers’ abilities to function at normal capacity. The purpose of this study was to describe occupational fatigue in pharmacists using exploratory factor analysis (EFA) – assessing whether dimensional structures used to describe occupational fatigue in other health professions fit pharmacist perceptions.MethodsA model was created to conceptualize ‘fatigue’ domains found in the literature. A priori, the two domains identified were physical fatigue (ex. physical discomfort), and mental fatigue (ex. trouble thinking clearly). These domains were operationalized and used to create a paper survey that was distributed to licensed pharmacists at a pharmacy conference. An EFA was conducted to identify the key domains underlying pharmacist perceptions of fatigue.ResultsA total of 283 surveys were distributed and 115 were returned and usable. Respondents were primarily white, female, worked 9.52 hours-per-day on average, and mean age of 39-years-old. The EFA suggested a statistically significant two-factor model (χ2 9.73, p=0.28; TLI 0.998, RMSEA 0.048), which included physical fatigue (α = 0.87) and mental fatigue (α = 0.82).DiscussionThe EFA yielded a structure similar to what was anticipated from the literature with physical and mental fatigue dimensions. This is just the first step in promoting systematic interventions to prevent or cope with fatigue and prevent the downstream patient, pharmacist, and institutional outcomes. By addressing fatigue and caring for employees, health care systems can take steps to work toward the Quadruple Aim.