bluuebunny/crossref_metadata_2025_split huggingface dataset:
Establishment of a Seronegative Occult Infection With an Active Hepatitis B Virus Reservoir Enriched of Vaccine Escape Mutations in a Vaccinated Infant After Liver Transplantation
Authors: Salpini Romina , Pietrobattista Andrea , Piermatteo Lorenzo , Basso Maria Sole , Bellocchi Maria C , Liccardo Daniela , Carioti Luca , Francalanci Paola , Aragri Marianna , Alkhatib Mohammed , Scutari Rossana , Candusso Manila , Ciotti Marco , Svicher Valentina 
Published: August 2019

Abstract
We describe the establishment of a seronegative occult hepatitis B virus (HBV) infection (OBI) in a successfully vaccinated infant who underwent liver transplantation from an donor positive for antibody to hepatitis B core antigen (anti-HBc). The use of highly sensitive droplet digital polymerase chain reaction assays revealed a not negligible and transcriptionally active intrahepatic HBV reservoir (circular covalently closed DNA, relaxed circular DNA, and pregenomic RNA: 5.6, 2.4, and 1.1 copies/1000 cells, respectively), capable to sustain ongoing viral production and initial liver damage. Next-generation sequencing revealed a peculiar enrichment of hepatitis B surface antigen vaccine-escape mutations that could have played a crucial role in OBI transmission. This clinical case highlights the pathobiological complexity and the diagnostic challenges underlying OBI.
Contextual factors affecting the integration of community health workers into the health system in Limpopo Province, South Africa
Authors: Jobson Geoffrey , Naidoo Nireshni , Matlakala Nthabiseng , Marincowitz Gert , Railton Jean , McIntyre James A , Struthers Helen E , Peters Remco P H 
Published: August 2019

Abstract

Background
Community health workers (CHWs) are an essential cadre in the health systems of many low- and middle-income countries. These workers provide a wide variety of services and are key to ongoing processes of task shifting within human immunodeficiency virus programmes in particular. Ward-based outreach teams (WBOTs) are South Africa’s latest iteration of the CHW programme and have been introduced as part of the National Department of Health’s Primary Health Care Re-engineering programme.

Methods
In order to assess the perceived effectiveness of the WBOTs in supporting the ongoing rollout of antiretroviral therapy, tuberculosis care and patient support, we conducted a qualitative investigation focusing on the perceived successes and challenges of the programme among CHWs, community leaders, healthcare workers and community members in the Mopani district, Limpopo province, South Africa.

Results
The CHW programme operates across these contexts, each associated with its own set of challenges and opportunities.

Conclusions
While these challenges may be interrelated, a contextual analysis provides a useful means of understanding the programme’s implementation as part of ongoing decision-making processes.
How to Investigate the Origins of Novelty: Insights Gained from Genetic, Behavioral, and Fitness Perspectives
Authors: Martin C H , McGirr J A , Richards E J , St. John M E 
Published: August 2019

SynopsisBiologists are drawn to the most extraordinary adaptations in the natural world, often referred to as evolutionary novelties, yet rarely do we understand the microevolutionary context underlying the origins of novel traits, behaviors, or ecological niches. Here we discuss insights gained into the origins of novelty from a research program spanning biological levels of organization from genotype to fitness in Caribbean pupfishes. We focus on a case study of the origins of novel trophic specialists on San Salvador Island, Bahamas and place this radiation in the context of other rapid radiations. We highlight questions that can be addressed about the origins of novelty at different biological levels, such as measuring the isolation of novel phenotypes on the fitness landscape, locating the spatial and temporal origins of adaptive variation contributing to novelty, detecting dysfunctional gene regulation due to adaptive divergence, and connecting behaviors with novel traits. Evolutionary novelties are rare, almost by definition, and we conclude that integrative case studies can provide insights into this rarity relative to the dynamics of adaptation to more common ecological niches and repeated parallel speciation, such as the relative isolation of novel phenotypes on fitness landscapes and the transient availability of ecological, genetic, and behavioral opportunities.
A Phylogenetic Analysis of the Dirt Ants, Basiceros (Formicidae: Myrmicinae): Inferring Life Histories Through Morphological Convergence
Authors: Probst Rodolfo S , Wray Brian D , Moreau Corrie S , Brandão Carlos R F 
Published: August 2019

Abstract
Ants of the genus Basiceros Schulz, 1906 are elusive species known only from Neotropical rainforests. Little information is available regarding their natural history, and nothing is known about the phylogenetic relationships among species within the genus. The genus has been the subject of some controversy regarding generic delimitation but is currently a member of the ‘Basiceros-genus group’ following recent classification changes. For mouthparts, labral and mandibular morphologies present considerable variation in the Basiceros-genus group, likely a result of adaptive evolution. In Basiceros, those differences can be observed in the labrum shape and the various degrees of development of the labral cleft and the clypeomandibular space. Here, in an attempt to illuminate the evolution of the group, species boundaries are tested for Basiceros. The evolutionary relationships of its species are investigated using molecular and morphological data. Bayesian inference and maximum likelihood analyses of a molecular dataset consisting of up to nine genes (three mitochondrial, six nuclear) and including samples from multiple populations of all known Basiceros taxa recovered the monophyly of the genus and of its species, with two well-resolved internal clades: the singularis clade and the disciger clade. Focusing on the female castes of Basiceros, an ancestral state reconstruction is presented for mandibles and labrum morphology. The results suggest that the labrum and clypeomandibular morphologies are highly labile, although phylogenetically important characters in the genus. Mouthpart traits indicate a strong correlated evolutionary history potentially associated with specialized feeding habits.
Civilians, Control, and Collaboration during Civil Conflict
Authors: Condra Luke N , Wright Austin L 
Published: August 2019

AbstractWhat affects civilian collaboration with armed actors during civil war? While theory and evidence confirm that harm by armed actors influences when and with whom civilians collaborate, we argue that collaboration is also a function of civilians’ perceptions of armed actors’ efforts to minimize collateral casualties. We test this argument using a series of nationwide surveys of Afghan civilians conducted quarterly between 2013 and 2015. Our data record civilian willingness to report roadside bombs to government authorities and perceptions of government and Taliban efforts to minimize civilian harm. Civilians are less (more) willing to collaborate with the government when they perceive the government (Taliban) carelessly using force, even after accounting for political sentiment, local security conditions, and a range of additional confounding factors. Moreover, our evidence suggests that perceived carelessness in the rival’s area of control influences collaboration. We discuss how these empirical results inform broader literatures on collaboration, conquest, occupation, and control.
Consumer health information and question answering: helping consumers find answers to their health-related information needs
Authors: Demner-Fushman Dina , Mrabet Yassine , Ben Abacha Asma 
Published: August 2019

Abstract

Objective
Consumers increasingly turn to the internet in search of health-related information; and they want their questions answered with short and precise passages, rather than needing to analyze lists of relevant documents returned by search engines and reading each document to find an answer. We aim to answer consumer health questions with information from reliable sources.

Materials and Methods
We combine knowledge-based, traditional machine and deep learning approaches to understand consumers’ questions and select the best answers from consumer-oriented sources. We evaluate the end-to-end system and its components on simple questions generated in a pilot development of MedlinePlus Alexa skill, as well as the short and long real-life questions submitted to the National Library of Medicine by consumers.

Results
Our system achieves 78.7% mean average precision and 87.9% mean reciprocal rank on simple Alexa questions, and 44.5% mean average precision and 51.6% mean reciprocal rank on real-life questions submitted by National Library of Medicine consumers.

Discussion
The ensemble of deep learning, domain knowledge, and traditional approaches recognizes question type and focus well in the simple questions, but it leaves room for improvement on the real-life consumers’ questions. Information retrieval approaches alone are sufficient for finding answers to simple Alexa questions. Answering real-life questions, however, benefits from a combination of information retrieval and inference approaches.

Conclusion
A pilot practical implementation of research needed to help consumers find reliable answers to their health-related questions demonstrates that for most questions the reliable answers exist and can be found automatically with acceptable accuracy.
The Parentage Disruption: A Comparative Approach
Authors: Kessler Guillaume 
Published: August 2019

AbstractThe bionormative and heteronormative models of parentage has been challenged by multiple factors: a cultural shift, which has led to the decline of marriage and the development of cohabitation, a technological evolution, which has made it possible to develop new reproductive technologies, and a legal change that has led to the recognition of same-sex relationships. However, the extent of this development has not yet been fully assessed. Rather than simply adapting the rules designed according to an outdated model, it would be better to break with it permanently. This article proposes to build a new system based on intent and care, on the basis of case law and doctrinal proposals from several countries. Drawing from the best interests of the child standard, it operates a distinction between the status of parent and progenitor: whatever the circumstances of the birth (natural procreation, adoption, assisted reproduction technology, or surrogacy) and the nature of the parents' relationship (same-sex or heterosexual, married or unmarried, engaged in a romantic relationship or not), parentage would be based on a formal statement and the question of genetics limited to the determination of identity and the right to know one's origins.
Reproduction of marginality: The labour market position of unemployed foreign citizens during economic recession in Iceland
Authors: Wojtyńska Anna , Skaptadóttir Unnur Dís 
Published: August 2019

Abstract
Following the economic crash in 2008, many migrants in Iceland lost their jobs and experienced deteriorating working conditions. In 2011, four years after the onset of the recession, the unemployment rates among the foreign population remained significantly higher than among Icelanders. In this article, we discuss experiences of unemployed migrants concerning their changed position on the labour market in order to highlight the different mechanisms of labour market exclusion. On the basis of research among registered unemployed foreign citizens, we analyse the main reasons for their difficulties in finding new employment. The main obstacles as reported by survey respondents and focus groups participants were limited knowledge of Icelandic, increased reluctance among Icelandic employers to hire foreigners and insufficient social networking with the native population.
Modelling the Effects of Dark Matter Substructure on Globular Cluster Evolution with the Tidal Approximation
Authors: Webb Jeremy J , Bovy Jo , Carlberg Raymond G , Gieles Mark 
Published: August 2019

Abstract
We present direct N-body simulations of tidally filling 30,000 M⊙ star clusters orbiting between 10 kpc and 100 kpc in galaxies with a range of dark matter substructure properties. The time-dependent tidal force is determined based on the combined tidal tensor of the galaxy’s smooth and clumpy dark matter components, the latter of which causes fluctuations in the tidal field that can heat clusters. The strength and duration of these fluctuations are sensitive to the local dark matter density, substructure fraction, sub-halo mass function, and the sub-halo mass-size relation. Based on the cold dark matter framework, we initially assume sub-halos are Hernquist spheres following a power-law mass function between 105 and 1011M⊙ and find that tidal fluctuations are too weak and too short to affect star cluster evolution. Treating sub-halos as point masses, to explore how denser sub-halos affect clusters, we find that only sub-halos with masses greater than 106M⊙ will cause cluster dissolution times to decrease. These interactions can also decrease the size of a cluster while increasing the velocity dispersion and tangential anisotropy in the outer regions via tidal heating. Hence increased fluctuations in the tidal tensor, especially fluctuations that are due to low-mass halos, do not necessarily translate into mass loss. We further conclude that the tidal approximation can be used to model cluster evolution in the tidal fields of cosmological simulations with a minimum cold dark matter sub-halo mass of 106M⊙, as the effect of lower-mass sub-halos on star clusters is negligible.
Arecibo 4.5/1.4/0.33-GHz polarimetric single-pulse emission survey
Authors: Olszanski Timothy E E , Mitra Dipanjan , Rankin Joanna M 
Published: August 2019

ABSTRACT
We report on an Arecibo 4.5-GHz polarimetric single-pulse survey of the brightest pulsars at high frequency within its sky. The high-frequency profiles are accompanied by a collection of both previously published and unpublished high quality 1.4- and 0.33-GHz observations. Here our analyses and discussion primarily involve the average and statistical properties of the 46 pulsars polarimetric pulse sequences, profile classification and frequency evolution, and polarimetric profiles and peak-occurrence histograms. In most cases both the fractional linear polarization and profile widths decrease with frequency as expected, but there are some exceptions. Similarly, we were able to review and/or extend the profile classifications for this population of pulsars and work out their beaming characteristics quantitatively showing that almost all show properties compatible with the core/double-cone emission beam model. The entirety of these observations’ average profiles are accessible for download.
Studying the morphology of reionization with the triangle correlation function of phases
Authors: Gorce Adélie , Pritchard Jonathan R 
Published: August 2019

ABSTRACT
We present a new statistical tool, called the triangle correlation function (TCF), inspired by the earlier work of Obreschkow et al. It is derived from the three-point correlation function and aims to probe the characteristic scale of ionized regions during the epoch of reionization from 21cm interferometric observations. Unlike most works, which focus on power spectrum, i.e. amplitude information, our statistic is based on the information we can extract from the phases of the Fourier transform of the ionization field. In this perspective, it may benefit from the well-known interferometric concept of closure phases. We find that this statistical estimator performs very well on simple ionization fields. For example, with well-defined fully ionized discs, there is a peaking scale, which we can relate to the radius of the ionized bubbles. We explore the robustness of the TCF when observational effects such as angular resolution and noise are considered. We also get interesting results on fields generated by more elaborate simulations such as 21CMFAST. Although the variety of sources and ionized morphologies in the early stages of the process make its interpretation more challenging, the nature of the signal can tell us about the stage of reionization. Finally, and in contrast to other bubble size distribution algorithms, we show that the TCF can resolve two different characteristic scales in a given map.
Probing the origin of stellar flares on M dwarfs using TESS data sectors 1–3
Authors: Doyle L , Ramsay G , Doyle J G , Wu K 
Published: August 2019

ABSTRACT
Detailed studies of the Sun have shown that sunspots and solar flares are closely correlated. Photometric data from Kepler/K2 has allowed similar studies to be carried out on other stars. Here, we utilize Transiting Exoplanet Survey Satellite (TESS) photometric 2-min cadence of 167 low-mass stars from Sectors 1 to 3 to investigate the relationship between star-spots and stellar flares. From our sample, 90 per cent show clear rotational modulation likely due to the presence of a large, dominant star-spot and we use this to determine a rotational period for each star. Additionally, each low-mass star shows one or more flares in its light curve and using Gaia Data Release 2 parallaxes and SkyMapper magnitudes we can estimate the energy of the flares in the TESS band-pass. Overall, we have 1834 flares from the 167 low-mass stars with energies from 6.0 × 1029 to 2.4 × 1035 erg. We find none of the stars in our sample show any preference for rotational phase, suggesting the lack of a correlation between the large, dominant star-spot, and flare number. We discuss this finding in greater detail and present further scenarios to account for the origin of flares on these low-mass stars.
K2 observations of the sdBV + dM/bd binaries PHL 457 and EQ Psc
Authors: Baran A S , Telting J H , Jeffery C S , Østensen R H , Vos J , Reed M D , Vŭcković M 
Published: August 2019

ABSTRACT
We present an analysis of two pulsating subdwarf B stars PHL 457 and EQ Psc observed during the K2 mission. The K2 light curves of both stars show variation consistent with irradiation of a cooler companion by the hot subdwarf. They also show higher frequency oscillations consistent with pulsation. Using new spectroscopic data, we measured the radial velocity, effective temperature, surface gravity, and helium abundance of both hot subdwarfs as a function of orbital phase. We confirm the previously published spectroscopic orbit of PHL 457, and present the first spectroscopic orbit of EQ Psc. The orbital periods are 0.313 and 0.801 d, respectively. For EQ Psc, we find a strong correlation between Teff and orbital phase, due to contribution of light from the irradiated companion. We calculated amplitude spectra, identified significant pulsation frequencies, and searched for multiplets and asymptotic period spacings. By means of multiplets and period spacing, we identified the degrees of several pulsation modes in each star. The g-mode multiplets indicate subsynchronous core rotation with periods of 4.6 d (PHL 457) and 9.4 d (EQ Psc). We made spectral energy disctribution (SED) fits of PHL 457 and EQ Psc using available broad-band photometry and Gaia data. While the SED of PHL 457 shows no evidence of a cool companion, the SED for EQ Psc clearly shows an infrared (IR) access consistent with a secondary with a temperature of about 6800 K and a radius of 0.23 R⊙. This is the first detection of an IR access in any sdB + dM binary.
There is no magnetic braking catastrophe: low-mass star cluster and protostellar disc formation with non-ideal magnetohydrodynamics
Authors: Wurster James , Bate Matthew R , Price Daniel J 
Published: August 2019

Abstract
We present results from the first radiation non-ideal magnetohydrodynamics (MHD) simulations of low-mass star cluster formation that resolve the fragmentation process down to the opacity limit. We model 50 M⊙ turbulent clouds initially threaded by a uniform magnetic field with strengths of 3, 5 10, and 20 times the critical mass-to-magnetic flux ratio, and at each strength, we model both an ideal and non-ideal (including Ohmic resistivity, ambipolar diffusion, and the Hall effect) MHD cloud. Turbulence and magnetic fields shape the large-scale structure of the cloud, and similar structures form regardless of whether ideal or non-ideal MHD is employed. At high densities (106 ≲ nH ≲ 1011 cm−3), all models have a similar magnetic field strength versus density relation, suggesting that the field strength in dense cores is independent of the large-scale environment. Albeit with limited statistics, we find no evidence for the dependence of the initial mass function on the initial magnetic field strength, however, the star formation rate decreases for models with increasing initial field strengths; the exception is the strongest field case where collapse occurs primarily along field lines. Protostellar discs with radii ≳ 20 au form in all models, suggesting that disc formation is dependent on the gas turbulence rather than on magnetic field strength. We find no evidence for the magnetic braking catastrophe, and find that magnetic fields do not hinder the formation of protostellar discs.
SDSS-IV MaNGA: environmental dependence of gas metallicity gradients in local star-forming galaxies
Authors: Lian Jianhui , Thomas Daniel , Li Cheng , Zheng Zheng , Maraston Claudia , Bizyaev Dmitry , Lane Richard R , Yan Renbin 
Published: August 2019

ABSTRACT
Within the standard model of hierarchical galaxy formation in a Λ cold dark matter universe, the environment of galaxies is expected to play a key role in driving galaxy formation and evolution. In this paper, we investigate whether and how the gas metallicity and the star formation surface density (ΣSFR) depend on galaxy environment. To this end, we analyse a sample of 1162 local, star-forming galaxies from the galaxy survey Mapping Nearby Galaxies at APO (MaNGA). Generally, both parameters do not show any significant dependence on environment. However, in agreement with previous studies, we find that low-mass satellite galaxies are an exception to this rule. The gas metallicity in these objects increases while their ΣSFR decreases slightly with environmental density. The present analysis of MaNGA data allows us to extend this to spatially resolved properties. Our study reveals that the gas metallicity gradients of low-mass satellites flatten and their ΣSFR gradients steepen with increasing environmental density. By extensively exploring a chemical evolution model, we identify two scenarios that are able to explain this pattern: metal-enriched gas accretion or pristine gas inflow with varying accretion time-scales. The latter scenario better matches the observed ΣSFR gradients, and is therefore our preferred solution. In this model, a shorter gas accretion time-scale at larger radii is required. This suggests that ‘outside–in quenching’ governs the star formation processes of low-mass satellite galaxies in dense environments.