bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cradles of the first stars: self-shielding, halo masses, and multiplicity
Authors: Skinner Danielle , Wise John H 
Published: January 2020

ABSTRACT
The formation of Population III (Pop III) stars is a critical step in the evolution of the early Universe. To understand how these stars affected their metal-enriched descendants, the details of how, why and where Pop III formation takes place needs to be determined. One of the processes that is assumed to greatly affect the formation of Pop III stars is the presence of a Lyman–Werner (LW) radiation background, that destroys H2, a necessary coolant in the creation of Pop III stars. Self-shielding can alleviate the effect the LW background has on the H2 within haloes. In this work, we perform a cosmological simulation to study the birthplaces of Pop III stars, using the adaptive mesh refinement code enzo. We investigate the distribution of host halo masses and its relationship to the LW background intensity. Compared to previous work, haloes form Pop III stars at much lower masses, up to a factor of a few, due to the inclusion of H2 self-shielding. We see no relationship between the LW intensity and host halo mass. Most haloes form multiple Pop III stars, with a median number of four, up to a maximum of 16, at the instance of Pop III formation. Our results suggest that Pop III star formation may be less affected by LW radiation feedback than previously thought and that Pop III multiple systems are common.
The Pristine Survey – VIII. The metallicity distribution function of the Milky Way halo down to the extremely metal-poor regime
Authors: Youakim K , Starkenburg E , Martin N F , Matijevič G , Aguado D S , Allende Prieto C , Arentsen A , Bonifacio P , Carlberg R G , González Hernández J I , Hill V , Kordopatis G , Lardo C , Navarro J F , Jablonka P , Sánchez Janssen R , Sestito F , Thomas G F , Venn K 
Published: January 2020

ABSTRACT
The Pristine survey uses narrow-band photometry to derive precise metallicities down to the extremely metal-poor regime ($ \rm [Fe/H] \lt -3$), and currently consists of over 4 million FGK-type stars over a sky area of $\sim 2500\, \mathrm{deg}^2$. We focus our analysis on a subsample of ∼80 000 main-sequence turn-off stars with heliocentric distances between 6 and 20 kpc, which we take to be a representative sample of the inner halo. The resulting metallicity distribution function (MDF) has a peak at $ \rm [Fe/H] =-1.6$, and a slope of Δ(LogN)/$\Delta \rm [Fe/H] = 1.0 \pm 0.1$ in the metallicity range of $-3.4\; \lt\; \rm [Fe/H]\; \lt -2.5$. This agrees well with a simple closed-box chemical enrichment model in this range, but is shallower than previous spectroscopic MDFs presented in the literature, suggesting that there may be a larger proportion of metal-poor stars in the inner halo than previously reported. We identify the Monoceros/TriAnd/ACS/EBS/A13 structure in metallicity space in a low-latitude field in the anticentre direction, and also discuss the possibility that the inner halo is dominated by a single, large merger event, but cannot strongly support or refute this idea with the current data. Finally, based on the MDF of field stars, we estimate the number of expected metal-poor globular clusters in the Milky Way halo to be 5.4 for $ \rm [Fe/H]\; \lt\; -2.5$ and 1.5 for $ \rm [Fe/H]\; \lt\; -3$, suggesting that the lack of low-metallicity globular clusters in the Milky Way is not due simply to statistical undersampling.
Simulated mass measurements of the young planet K2-33b
Authors: Klein Baptiste , Donati J-F 
Published: January 2020

ABSTRACT
In this paper, we carry out simulations of radial velocity (RV) measurements of the mass of the 8–11 Myr Neptune-sized planet K2-33b using high-precision near-infrared velocimeters like SPIRou at the Canada–France–Hawaii Telescope. We generate an RV curve containing a planet signature and a realistic stellar activity signal, computed for a central wavelength of 1.8 µm and statistically compatible with the light curve obtained with K2. The modelled activity signal includes the effect of time-evolving dark and bright surface features hosting a 2 kG radial magnetic field, resulting in an RV signal of semi-amplitude ∼30 m s−1. Assuming a 3-month visibility window, we build RV time series including Gaussian white noise from which we retrieve the planet mass while filtering the stellar activity signal using Gaussian process regression. We find that 35/50 visits spread over three consecutive bright-time runs on K2-33 allow one to reliably detect planet RV signatures of, respectively, 10 and 5 m s−1 at precisions &gt;3σ. We also show that 30 visits may end up being insufficient in some cases to provide a good coverage of the stellar rotation cycle, with the result that the planet signature can go undetected or the mass estimation be plagued by large errors.
Evolution of Transcriptional Repressors Impacts Caenorhabditis Vulval Development
Authors: Chamberlin Helen M , Jain Ish M , Corchado-Sonera Marcos , Kelley Leanne H , Sharanya Devika , Jama Abdulrahman , Pabla Romy , Dawes Adriana T , Gupta Bhagwati P 
Published: January 2020

Abstract
Comparative genomic sequence analysis has found that the genes for many chromatin-associated proteins are poorly conserved, but the biological consequences of these sequence changes are not understood. Here, we show that four genes identified for an Inappropriate Vulval cell Proliferation (ivp) phenotype in the nematode Caenorhabditis briggsae exhibit distinct functions and genetic interactions when compared with their orthologs in C. elegans. Specifically, we show that the four C. briggsae ivp genes encode the noncanonical histone HTZ-1/H2A.z and three nematode-specific proteins predicted to function in the nucleus. The mutants exhibit ectopic vulval precursor cell proliferation (the multivulva [Muv] phenotype) due to inappropriate expression of the lin-3/EGF gene, and RNAseq analysis suggests a broad role for these ivp genes in transcriptional repression. Importantly, although the C. briggsae phenotypes have parallels with those seen in the C. elegans synMuv system, except for the highly conserved HTZ-1/H2A.z, comparable mutations in C. elegans ivp orthologs do not exhibit synMuv gene interactions or phenotypes. These results demonstrate the evolutionary changes that can underlie conserved biological outputs and argue that proteins critical to repress inappropriate expression from the genome participate in a rapidly evolving functional landscape.
Evolutionary Dynamics of Abundant 7-bp Satellites in the Genome ofDrosophila virilis
Authors: Flynn Jullien M , Long Manyuan , Wing Rod A , Clark Andrew G 
Published: January 2020

AbstractThe factors that drive the rapid changes in abundance of tandem arrays of highly repetitive sequences, known as satellite DNA, are not well understood. Drosophila virilis has one of the highest relative amounts of simple satellites of any organism that has been studied, with an estimated &gt;40% of its genome composed of a few related 7-bp satellites. Here, we use D. virilis as a model to understand technical biases affecting satellite sequencing and the evolutionary processes that drive satellite composition. By analyzing sequencing data from Illumina, PacBio, and Nanopore platforms, we identify platform-specific biases and suggest best practices for accurate characterization of satellites by sequencing. We use comparative genomics and cytogenetics to demonstrate that the highly abundant AAACTAC satellite family arose from a related satellite in the branch leading to the virilis phylad 4.5–11 Ma before exploding in abundance in some species of the clade. The most abundant satellite is conserved in sequence and location in the pericentromeric region but has diverged widely in abundance among species, whereas the satellites nearest the centromere are rapidly turning over in sequence composition. By analyzing multiple strains of D. virilis, we saw that the abundances of two centromere-proximal satellites are anticorrelated along a geographical gradient, which we suggest could be caused by ongoing conflicts at the centromere. In conclusion, we illuminate several key attributes of satellite evolutionary dynamics that we hypothesize to be driven by processes including selection, meiotic drive, and constraints on satellite sequence and abundance.
ADAPT identifies an ESCRT complex composition that discriminates VCaP from LNCaP prostate cancer cell exosomes
Authors: Hornung Tassilo , O’Neill Heather A , Logie Stephen C , Fowler Kimberly M , Duncan Janet E , Rosenow Matthew , Bondre Aniket S , Tinder Teresa , Maher Varun , Zarkovic Jelena , Zhong Zenyu , Richards Melissa N , Wei Xixi , Miglarese Mark R , Mayer Günter , Famulok Michael , Spetzler David 
Published: January 2020

Abstract
Libraries of single-stranded oligodeoxynucleotides (ssODNs) can be enriched for sequences that specifically bind molecules on naïve complex biological samples like cells or tissues. Depending on the enrichment strategy, the ssODNs can identify molecules specifically associated with a defined biological condition, for example a pathological phenotype, and thus are potentially useful for biomarker discovery. We performed ADAPT, a variant of SELEX, on exosomes secreted by VCaP prostate cancer cells. A library of ∼1011 ssODNs was enriched for those that bind to VCaP exosomes and discriminate them from exosomes derived from LNCaP prostate cancer cells. Next-generation sequencing (NGS) identified the best discriminating ssODNs, nine of which were resynthesized and their discriminatory ability confirmed by qPCR. Affinity purification with one of the sequences (Sequence 7) combined with LC–MS/MS identified its molecular target complex, whereof most proteins are part of or associated with the multiprotein ESCRT complex participating in exosome biogenesis. Within this complex, YBX1 was identified as the directly-bound target protein. ADAPT thus is able to differentiate exosomes from cancer cell subtypes from the same lineage. The composition of ESCRT complexes in exosomes from VCaP versus LNCaP cells might constitute a discriminatory element between these prostate cancer subtypes.
Modulated control of DNA supercoiling balance by the DNA-wrapping domain of bacterial gyrase
Authors: Hobson Matthew J , Bryant Zev , Berger James M 
Published: January 2020

AbstractNegative supercoiling by DNA gyrase is essential for maintaining chromosomal compaction, transcriptional programming, and genetic integrity in bacteria. Questions remain as to how gyrases from different species have evolved profound differences in their kinetics, efficiency, and extent of negative supercoiling. To explore this issue, we analyzed homology-directed mutations in the C-terminal, DNA-wrapping domain of the GyrA subunit of Escherichia coli gyrase (the ‘CTD’). The addition or removal of select, conserved basic residues markedly impacts both nucleotide-dependent DNA wrapping and supercoiling by the enzyme. Weakening CTD–DNA interactions slows supercoiling, impairs DNA-dependent ATP hydrolysis, and limits the extent of DNA supercoiling, while simultaneously enhancing decatenation and supercoil relaxation. Conversely, strengthening DNA wrapping does not result in a more extensively supercoiled DNA product, but partially uncouples ATP turnover from strand passage, manifesting in futile cycling. Our findings indicate that the catalytic cycle of E. coli gyrase operates at high thermodynamic efficiency, and that the stability of DNA wrapping by the CTD provides one limit to DNA supercoil introduction, beyond which strand passage competes with ATP-dependent supercoil relaxation. These results highlight a means by which gyrase can evolve distinct homeostatic supercoiling setpoints in a species-specific manner.
Use of radiomics for the prediction of local control of brain metastases after stereotactic radiosurgery
Authors: Mouraviev Andrei , Detsky Jay , Sahgal Arjun , Ruschin Mark , Lee Young K , Karam Irene , Heyn Chris , Stanisz Greg J , Martel Anne L 
Published: January 2020

Abstract

Background
Local response prediction for brain metastases (BM) after stereotactic radiosurgery (SRS) is challenging, particularly for smaller BM, as existing criteria are based solely on unidimensional measurements. This investigation sought to determine whether radiomic features provide additional value to routinely available clinical and dosimetric variables to predict local recurrence following SRS.

Methods
Analyzed were 408 BM in 87 patients treated with SRS. A total of 440 radiomic features were extracted from the tumor core and the peritumoral regions, using the baseline pretreatment volumetric post-contrast T1 (T1c) and volumetric T2 fluid-attenuated inversion recovery (FLAIR) MRI sequences. Local tumor progression was determined based on Response Assessment in Neuro-Oncology‒BM criteria, with a maximum axial diameter growth of &gt;20% on the follow-up T1c indicating local failure. The top radiomic features were determined based on resampled random forest (RF) feature importance. An RF classifier was trained using each set of features and evaluated using the area under the receiver operating characteristic curve (AUC).

Results
The addition of any one of the top 10 radiomic features to the set of clinical features resulted in a statistically significant (P &lt; 0.001) increase in the AUC. An optimized combination of radiomic and clinical features resulted in a 19% higher resampled AUC (mean = 0.793; 95% CI = 0.792–0.795) than clinical features alone (0.669, 0.668–0.671).

Conclusions
The increase in AUC of the RF classifier, after incorporating radiomic features, suggests that quantitative characterization of tumor appearance on pretreatment T1c and FLAIR adds value to known clinical and dosimetric variables for predicting local failure.
The Orestes Melt Zone, McMurdo Dry Valleys, Antarctica: Spatially Distributed Melting Regimes in a Contact Melt Zone, with Implications for the Formation of Rapakivi and Albite Granites
Authors: Currier R M , Flood T P 
Published: January 2020

Abstract
The Orestes Melt Zone (OMZ) is a massive contact melt zone (∼20 m thick by several kilometers long), located in the McMurdo Dry Valleys of Antarctica. The OMZ formed at shallow crustal depths by melting of the A-type Orestes Granite owing to intrusion of the underlying, doleritic Basement Sill. The OMZ can be divided broadly into two melting facies. The upper melting facies is distal from the contact and formed by melting at low temperature and water-saturated, or near water-saturated, conditions. The lower melting facies is proximal to the contact and formed by melting at high temperature and water-undersaturated conditions. Separate melting reactions occurred in both of the melting facies, resulting in distinct textures and melt compositions. Melting in the distal facies generated melts with compositions that plot near a predicted eutectic composition. Melting in the proximal facies was accomplished in part by replacement reactions in restitic feldspars. These reactions resulted in the development of plagioclase mantles on both restitic plagioclase and K-feldspar, and melt compositions that diverged from predicted minimum melt along an unexpected path, towards enrichment in orthoclase component. Thermal modeling indicates that this melt zone was active for a minimum of ∼150 years, with a contact temperature of ∼900 °C. Upon cooling, recrystallization generated ocellar textures around restitic quartz, as well as faceted albite as a late-stage product. Observations of the OMZ, combined with thermal modeling, provide new insights into the origin of rapakivi and albite granites. This study has implications for the origin of these two associated granite types in other geological settings.
Epidemiology, morbidity and mortality in Behçet’s disease: a cohort study using The Health Improvement Network (THIN)
Authors: Thomas Tom , Chandan Joht Singh , Subramanian Anuradhaa , Gokhale Krishna , Gkoutos George , Harper Lorraine , Buckley Christopher , Chandratre Priyanka , Raza Karim , Situnayake Deva , Nirantharakumar Krishnarajah 
Published: January 2020

Abstract

Objectives
The epidemiology of Behçet’s disease (BD) has not been well characterized in the UK. Evidence on the risk of cardiovascular disease, thromboembolic disease and mortality in patients with BD compared with the general population is scarce.

Methods
We used a large UK primary care database to investigate the epidemiology of BD. A retrospective matched cohort study was used to assess the following outcomes: risk of cardiovascular, thromboembolic disease and mortality. Controls were selected at a 1:4 ratio (age and gender matched). Cox proportional hazard models were used to derive adjusted hazard ratios (aHR).

Results
The prevalence of BD was 14.61 (95% CI 13.35–15.88) per 100 000 population in 2017. A total of 1281 patients with BD were compared with 5124 age- and gender-matched controls. There was significantly increased risk of ischaemic heart disease [aHR 3.09 (1.28–7.44)], venous thrombosis [aHR 4.80 (2.42–9.54)] and mortality [aHR 1.40 (1.07–1.84)] in patients with BD compared with corresponding controls. Patients with BD were at higher risk of pulmonary embolism compared with corresponding controls at baseline [adjusted odds ratio 4.64 (2.66–8.09), P &lt; 0.0001]. The majority of patients with pulmonary embolism and a diagnosis of BD had pulmonary embolism preceding the diagnosis of BD, not after (87.5%; n = 28/32).

Conclusion
BD has a higher prevalence than previously thought. Physicians should be aware of the increased risk of developing ischaemic heart disease, stroke/transient ischaemic attack and deep venous thrombosis in patients with BD at an earlier age compared with the general population. Risk of embolism in patients with BD might vary across the disease course.
Frontal alpha asymmetry in alcohol-related intimate partner violence
Authors: Fink Brandi C , Howell Breannan C , Salway Sarah , Cavanagh James F , Hamilton Derek A , Claus Eric D , Frost Madeline E 
Published: January 2020

Abstract
Electroencephalographic (EEG) frontal alpha asymmetry (FAA) has been associated with differences in the experience and expression of emotion, motivation and anger in normal and clinical populations. The current study is the first to investigate FAA in alcohol-related intimate partner violence. EEG was recorded from 23 distressed violent (DV) and 15 distressed nonviolent (DNV) partners during a placebo-controlled alcohol administration and emotion-regulation study. The State-Trait Anger Expression Inventory 2 was used to evaluate anger experiences and was collected from both participants and their partners. During baseline, acute alcohol intoxication DV partners had significantly greater right FAA, whereas DNV partners showed greater left FAA. Both partner types demonstrated significantly greater right FAA during the placebo beverage condition of the emotion-regulation task when viewing evocative partner displays of contempt, belligerence, criticism, defensiveness and stonewalling, but greater left FAA during acute alcohol intoxication. Although no group differences were found in the emotion-regulation task, partner self-reported anger experiences accounted for 67% of the variance in the FAA of DV participants when intoxicated and viewing evocative stimuli, suggesting dyadic processes are important in understanding alcohol-related IPV. These findings suggest that FAA could index the affective and motivational determinants through which alcohol is related to IPV.
Chairs of academic events: The investments and academic impact
Authors: Trøst Hansen Thomas , Ren Carina 
Published: January 2020

AbstractEvery year, tens of thousands of academics engage in unfamiliar tasks related to catering, hotel booking, and transportation. They do so as chairs of the academic event. We do not know much about these chairmanships; neither how the researchers engage nor whether it is worthwhile from an academic point of view. Based on interviews with twenty-three researchers at six Danish universities and an analytical framework informed by the concept of credibility cycles, we analyze the academic chairmanship and how it impacts the knowledge production process of the chair. The article argues that the chairmanship is a multifaceted investment, which includes a range of non-academic tasks. The investment is a source for the following forms of credibility network, buzz, and recognition and the chairs gain access to a range of other potential exchanges. The study concludes that chairmanships of academic events are surprisingly similar across disciplines and that they are potential science policy instruments.
Molecular fossils reveal ancient associations of dsDNA viruses with several phyla of fungi
Authors: Gong Zhen , Zhang Yu , Han Guan-Zhu 
Published: January 2020

Abstract
Little is known about the infections of double-stranded DNA (dsDNA) viruses in fungi. Here, we use a paleovirological method to systematically identify the footprints of past dsDNA virus infections within the fungal genomes. We uncover two distinct groups of endogenous nucleocytoplasmic large DNA viruses (NCLDVs) in at least seven fungal phyla (accounting for about a third of known fungal phyla), revealing an unprecedented diversity of dsDNA viruses in fungi. Interestingly, one fungal dsDNA virus lineage infecting six fungal phyla is closely related to the giant virus Pithovirus, suggesting giant virus relatives might widely infect fungi. Co-speciation analyses indicate fungal NCLDVs mainly evolved through cross-species transmission. Taken together, our findings provide novel insights into the diversity and evolution of NCLDVs in fungi.
Contemporary Strategies in Pilon Fixation
Authors: Hebert-Davies Jonah , Kleweno Conor P. , Nork Sean E. 
Published: January 2020

Summary:
The treatment of tibial pilon fractures has evolved substantially over the past decades due to ever-increasing high-energy injuries. Open reduction and internal fixation of these intra-articular fractures requires an appreciation for a number of basic principles: respect the soft tissues, understand the fracture pattern, use safe surgical approaches, and provide stability that allows for early motion of the ankle. Surgical strategy should be customized based on the fracture pattern, access needed for fracture visualization and reduction, and status of the soft tissues. Given the ability to obtain an accurate stable reduction, smaller implants are typically adequate using multiple small incisions. We view this surgical tactic as continuing the evolution of complex fracture treatment whose origins lie in the influences of pioneers such as Dr Sigvard T. Hansen Jr.