bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of Postpartum Hemorrhage Admission Risk Factor Stratification in a Large Obstetrics Population
Authors: Ruppel Halley , Liu Vincent X. , Gupta Neeru R. , Soltesz Lauren , Escobar Gabriel J. 
Published: May 2020

Abstract
Objective This study aimed to evaluate the performance of the California Maternal Quality Care Collaborative (CMQCC) admission risk criteria for stratifying postpartum hemorrhage risk in a large obstetrics population.
Study Design Using detailed electronic health record data, we classified 261,964 delivery hospitalizations from Kaiser Permanente Northern California hospitals between 2010 and 2017 into high-, medium-, and low-risk groups based on CMQCC criteria. We used logistic regression to assess associations between CMQCC risk groups and postpartum hemorrhage using two different postpartum hemorrhage definitions, standard postpartum hemorrhage (blood loss ≥1,000 mL) and severe postpartum hemorrhage (based on transfusion, laboratory, and blood loss data). Among the low-risk group, we also evaluated associations between additional present-on-admission factors and severe postpartum hemorrhage.
Results Using the standard definition, postpartum hemorrhage occurred in approximately 5% of hospitalizations (n = 13,479), with a rate of 3.2, 10.5, and 10.2% in the low-, medium-, and high-risk groups. Severe postpartum hemorrhage occurred in 824 hospitalizations (0.3%), with a rate of 0.2, 0.5, and 1.3% in the low-, medium-, and high-risk groups. For either definition, the odds of postpartum hemorrhage were significantly higher in medium- and high-risk groups compared with the low-risk group. Over 40% of postpartum hemorrhages occurred in hospitalizations that were classified as low risk. Among the low-risk group, risk factors including hypertension and diabetes were associated with higher odds of severe postpartum hemorrhage.
Conclusion We found that the CMQCC admission risk assessment criteria stratified women by increasing rates of severe postpartum hemorrhage in our sample, which enables early preparation for many postpartum hemorrhages. However, the CMQCC risk factors missed a substantial proportion of postpartum hemorrhages. Efforts to improve postpartum hemorrhage risk assessment using present-on-admission risk factors should consider inclusion of other nonobstetrical factors.
Trends in the Treatment of Pectus Excavatum in the Netherlands
Authors: Zuidema Wietse P. , van der Steeg Alida F. W. , Oosterhuis Jan W. A. , van Heurn Ernest 
Published: May 2020

Abstract
Introduction Pectus excavatum (PE) is the most common deformity of the anterior chest wall and can be corrected surgically with different techniques. In the past years, medical literature suggests that the minimal invasive surgical correction of PE (MIRPE) has currently become the operation technique of choice in Europe, and the number of PE patients undergoing surgery has increased. The aim of this study was to evaluate trends in the number of patients operated on and the surgical techniques generally used in patients with PE in the Netherlands.
Materials and Methods From the registration by Statistics Netherlands, the numbers of live births and gender were obtained for the period 1980 to 2017. Furthermore, from the Dutch hospital registration performed by Kiwa Prismant systems, the number of total surgical procedures of PE patients from the period 1998 to 2017, and the numbers of open and MIRPE surgery were obtained over the period 2005 to 2013.
Results The birth rate in Netherlands has stayed more or less stable in the last two decades. The number of PE patients asking for correction, however, has increased. In addition, the percentage of thoracoscopic assisted correction has increased.
Conclusion The increase in correction of PE is not due to an increased incidence but to an increase of patient wishes. The use of MIRPE is gaining popularity over time.
Tuning environmental timescales to evolve and maintain generalists
Authors: Sachdeva Vedant , Husain Kabir , Sheng Jiming , Wang Shenshen , Murugan Arvind 
Published: May 2020

Significance
Generalists, or jacks-of-all-trades, that are fit across diverse environments can be difficult to evolve since they may not be as fit as a specialist in any particular environment. Such generalists are sought in immunology, where broadly neutralizing antibodies that can detect a broad variety of strains of a rapidly changing virus like HIV are often hard to evolve. Here, we find that generalists are most easily evolved in the most poorly understood regime of evolution—where the environment changes are neither fast nor slow but on the same timescale as evolutionary response of the population. Our methods let us propose temporal vaccination protocols, such as a chirp, that exploit this highly dynamic regime of evolution.
Modulation of hippocampal brain networks produces changes in episodic simulation and divergent thinking
Authors: Thakral Preston P. , Madore Kevin P. , Kalinowski Sarah E. , Schacter Daniel L. 
Published: May 2020

SignificanceStudies have suggested a role for episodic memory in imagining future events and thinking creatively. Here, we tested the causal role played by episodic memory in future imagining and creative thinking by using fMRI-guided transcranial magnetic stimulation to disrupt neural activity in the hippocampus, a brain region involved in episodic memory. After transcranial magnetic stimulation, participants generated fewer episodic details when imagining future events and produced fewer creative ideas. fMRI analyses revealed that these behavioral reductions were linked to a reduction in hippocampal activity. Our findings have implications for brain targets and interventions to alleviate declines in memory, imagination, creativity, and other sorts of adaptive episodic functioning.
A methyl-TROSY approach for NMR studies of high-molecular-weight DNA with application to the nucleosome core particle
Authors: Abramov Gili , Velyvis Algirdas , Rennella Enrico , Wong Leo E. , Kay Lewis E. 
Published: May 2020

Significance
Many of the important functions in the cell are performed by high-molecular-weight complexes that contain both protein and nucleic acid components. Although developments in solution NMR spectroscopy have facilitated the study of the protein portions of these complexes, similar quantitative studies of the nucleic acids have proven challenging. Here we describe an approach for labeling DNA molecules with methyl-group probes at specific sites, followed by the use of optimized NMR methods to obtain high-quality data in studies of these large molecular complexes. Studies of both the DNA and protein components of the nucleosome core particle are presented, including an investigation of how CpG methylation, an important epigenetic mark, affects the structural dynamics of the particle.
Connective frequencies in child-directed texts
Authors: Tellings Agnes E. J. M. , Penning de Vries Bart 
Published: May 2020

Abstract
Starting from a usage-based perspective of language acquisition, the present study investigates the occurrence of
connectives in BasiLex, an 11.5 million word corpus of texts Dutch children encounter during the primary school years (grades 1–6).
Specifically, we investigate how connective frequencies change across grades, how these changes reflect the theorized orders of connective
acquisition in the work of Bloom et al. (1980) and Evers-Vermeul & Sanders (2009), and we make a comparison with the frequencies of connectives in the adult written language
corpus Celex. Briefly summarized, our findings show that the numbers of connectives increase sharply after grade 1 and then more steadily
across grades 2 to 6; we see some reflection of the connective acquisition theory of Evers-Vermeul & Sanders in the connective
frequencies in texts offered to children; and we see some remarkable similarities between connective frequencies in the adult corpus Celex
as compared to connective frequencies in grade 1 and grade 6 texts in BasiLex. Our findings suggest that the written input offered to
children harmonizes with theoretical approaches that emphasize the incremental growth of word knowledge in children as a function of
exposure.
Electron channelling: challenges and opportunities for compositional analysis of nanowires by TEM
Authors: Ek M , Lehmann Sebastian , Wallenberg Reine 
Published: May 2020

Abstract
Energy dispersive x-ray spectroscopy in a transmission electron microscope is often the first method employed to characterize the composition of nanowires. Ideally, it should be accurate and sensitive down to fractions of an atomic percent, and quantification results are often reported as such. However, one can often get substantial errors in accuracy even though the precision is high: for nanowires it is common for the quantified V/III atomic ratios to differ noticeably from 1. Here we analyse the origin of this systematic error in accuracy for quantification of the composition of III–V nanowires. By varying the electron illumination direction, we find electron channelling to be the primary cause, being responsible for errors in quantified V/III atomic ratio of 50%. Knowing the source of the systematic errors is required for applying appropriate corrections. Lastly, we show how channelling effects can provide information on the crystallographic position of dopants.
Role of protic ionic liquid concentration in proton conducting polymer electrolytes for improved electrical and thermal properties
Authors: Nair Manjula G , Mohapatra Saumya R , Garda Marie-Rose , Patanair Bindu , Saiter-Fourcin Allisson , Thomas Sabu 
Published: May 2020

AbstractProtic ionic liquids (PILs) in the acidic medium are known to show higher ionic conductivity than neat PIL or PIL in alkaline media. Hence, polymer electrolyte membranes (PEM) containing both PIL and acids are considered ideal for non-humidified intermediate temperature PEM fuel cells. Herein, we report non-aqueous proton conducting PEM made up of diethylmethylammonium trifluoromethanesulfonate; [dema][TfO] and neat phosphoric acid (H3PO4) with poly (vinylidene fluoride-co-hexafluoropropylene); PVDF-HFP as the host matrix. The presence of PIL significantly modified the structure and microstructure of the electrolyte films with the emergence of micropores in the PIL containing membranes. SEM images suggest leaching of PIL and phosphoric acid above 80 wt% of PIL in the electrolyte membranes. Thermogravimetric studies show that the dehydration in the PEM films due to phosphoric acid condensation at 100 °C–200 °C region is arrested by the presence of PIL. The maximum ionic conductivity at room temperature is ∼6.3 × 10−4S cm−1at 40 wt% of [dema][TfO] addition, which is two orders higher than that of the primary electrolyte (PE) containing only phosphoric acid in PVDF-HFP. This high conductivity in PEM films can be correlated to the increase in polarβandγphases as well as a drop in the total crystallinity fraction in the film. The study using dielectric spectroscopy reveals a strong coupling of ionic conductivity with the structural or segmental relaxation of the PVDF-HFP due to the presence of [dema][TfO] in the PEMs.
Network Structure of Physical, Cognitive, and Emotional Symptoms at Preseason Baseline in Student Athletes with Attention-Deficit/ Hyperactivity Disorder
Authors: Iverson Grant L , Jones Payton J , Karr Justin E , Maxwell Bruce , Zafonte Ross , Berkner Paul D , McNally Richard J 
Published: May 2020

Abstract

Objective
Preexisting attention-deficit/hyperactivity disorder (ADHD) may be a risk factor for worse outcome following sport-related concussion. We used a statistical and psychometric approach known as network analysis to examine the architecture of physical, cognitive, and emotional symptoms at preseason baseline among student athletes with ADHD.

Method
A cohort of 44,527 adolescent student athletes completed baseline preseason testing with ImPACT® between 2009 and 2015. A subsample of athletes reporting a diagnosis of ADHD and at least one symptom were included in this study (N = 3,074; 14–18 years old, 32.7% girls). All participants completed the 22-item Post-Concussion Symptom Scale at preseason baseline.

Results
Student athletes reported high frequencies of difficulty concentrating (boys/girls = 50.7%/59.4%), emotional symptoms (nervousness: boys/girls = 30.2%/51.0%; irritability: boys/girls = 23.6%/34.8%; sadness: boys/girls = 21.4%/39.7%), sleep/arousal-related symptoms (trouble falling asleep: boys/girls = 39.5%/49.4%; sleeping less than usual: boys/girls = 36.2%/43.4%; and fatigue: boys/girls = 29.8%/36.4%), and headaches (boys/girls = 27.6%/39.0%) during preseason baseline testing. The most central symptoms included dizziness, which was related to multiple somatic symptoms, and increased emotionality, which was related to a cluster of emotional symptoms. Girls reported symptoms at a greater frequency than boys, and there was evidence for variance in the global strength of the symptom network across gender, but not specific intersymptom relationships.

Conclusion
In the absence of injury, symptoms that commonly occur after concussion interact and potentially reinforce each other among student athletes with ADHD at preseason. Symptoms common in ADHD (i.e., difficulty concentrating) are not necessarily the most central within the symptom network. These findings may inform more precise interventions for athletes with ADHD and prolonged recovery following concussion.
Ecological factors driving pollination success in an orchid that mimics a range of Fabaceae
Authors: Scaccabarozzi Daniela , Guzzetti Lorenzo , Phillips Ryan D , Milne Lynne , Tommasi Nicola , Cozzolino Salvatore , Dixon Kingsley W 
Published: May 2020

AbstractRewarding plants can enhance the pollination success of co-occurring plants pollinated by food mimicry. However, it is not always possible to readily discern between the effect of model and magnet species. Here, we tested for mimicry of co-occurring Fabaceae by the rewardless Diuris magnifica (Orchidaceae) and whether the number of flowers of Fabaceae, habitat remnant size and frequency of conspecifics, influenced the pollination success of D. magnifica. Trichocolletes bees were the primary pollinators of D. magnifica, on which they displayed similar behaviour as seen when feeding on Fabaceae. Quantification of spectral reflectance suggested that flowers of Bossiaea eriocarpa, Daviesia divaricata and Jacksonia sternbergiana may represent models for D. magnifica, whereas Hardenbergia comptoniana strongly differed in colour. Orchid pollination success was not directly affected by the number of model flowers, but the pollination rate was enhanced by increased numbers of Hardenbergia flowers. Pollination success of the orchid decreased with higher density of conspecifics, but did not exhibit a significant relationship with Trichocolletes occurrence, possibly because of the contribution of sub-optimal pollinator species. Fruit set of the orchid was greater in larger habitat remnants. Overall, pollination success of D. magnifica is affected by ecological factors related to the effectiveness of mimicry, numbers of co-flowering plants and anthropogenic landscape alteration.
Potential hazards of recent trends in liberal iron use for renal anemia
Authors: Nakanishi Takeshi , Kuragano Takahiro 
Published: May 2020

Abstract
A randomized controlled trial,the Proactive IV Iron Therapy in Haemodialysis Patients (PIVOTAL), has recently shown that a high-dose (‘proactive’) intravenous iron regimen was superior to a low-dose (‘reactive’) regimen for hemodialysis patient outcomes and overall safety. However, even in the low-dose group, a substantial amount of iron was administered to maintain serum ferritin &gt;200 ng/mL. This type of comparison may have strongly affected the safety results. Iron has two opposite effects on erythropoiesis: it activates erythroid differentiation directly by supplying iron but inhibits it indirectly by stimulating hepcidin and enhancing oxidative stress. Hepcidin plays an essential role not only in iron homeostasis and the anemia of chronic kidney disease, but also in its complications such as atherosclerosis and infection. Its main stimulation by iron—and to a lesser degree by inflammation—should urge clinicians to avoid prescribing excessive amounts of iron. Furthermore, as serum ferritin is closely correlated with serum hepcidin and iron storage, it would seem preferable to rely mainly on serum ferritin to adjust iron administration, defining an upper limit for risk reduction. Based on our estimations, the optimal range of serum ferritin is ∼50–150 ng/mL, which is precisely within the boundaries of iron management in Japan. Considering the contrasting ranges of target ferritin levels between end-stage renal disease patients in Japan and the rest of the world, the optimal range proposed by us will probably be considered as unacceptable by nephrologists abroad. Only well-balanced, randomized controlled trials with both erythropoiesis-stimulating agents and iron will allow us to settle this controversy.
Lost in Transmission? John Berger and the Origins of Ways of Seeing (1972)
Authors: Conlin Jonathan 
Published: May 2020

Abstract
The documentary series Ways of Seeing was broadcast on BBC television in January 1972. Directed by Mike Dibb and presented by the marxist critic John Berger, the series addressed the canon of western art history as well as contemporary consumer culture. The conspicuous use of cross-cutting and music along with Berger’s emphatic ‘talking-head’ delivery were employed to dispel the aura enveloping ‘original’ artworks, and reveal the technologies by which art historians, curators and advertising agencies shored up a capitalist, western, male social order. The series and its associated book were canonical for the nascent disciplines of media and culture studies. Drawing on scripts and other materials from the BBC, Berger and Dibb archives, this essay explains how the four episodes were conceived and executed. It places the series in the context of Berger’s prior activity as artist, art critic, presenter and author, noting the influence of Frederick Antal, Walter Benjamin and others. It concludes that Berger’s charisma and the mastery of the relatively new technology of colour television displayed by the series undermined its intent: rather than encouraging viewers to use images in framing their own personal narratives, its message was consumed as an invitation to view all images in political terms.
Accounting for Wealth-Inequality Dynamics: Methods, Estimates, and Simulations for France
Authors: Garbinti Bertrand , Goupille-Lebret Jonathan , Piketty Thomas 
Published: May 2020

Abstract
Measuring and understanding the evolution of wealth inequality is a key challenge for researchers, policy makers, and the general public. This paper breaks new ground on this topic by presenting a new method to estimate and study wealth inequality. This method combines fiscal data with household surveys and national accounts in order to provide annual wealth distribution series, with detailed breakdowns by percentiles, age, and assets. Using the case of France as an illustration, we show that the resulting series can be used to better analyze the evolution and the determinants of wealth-inequality dynamics over the 1970–2014 period. We show that the decline in wealth inequality ends in the early 1980s, marking the beginning of a rise in the top 1% wealth share, though with significant fluctuations due largely to asset price movements. Rising inequality in savings rates coupled with highly stratified rates of returns has led to rising wealth concentration in spite of the opposing effect of house price increases. We develop a simple simulation model highlighting how changes in the combination of unequal savings rates, rates of return, and labor earnings that occurred in the early 1980s generated large multiplicative effects that led to radically different steady-state levels of wealth inequality. Taking advantage of the joint distribution of income and wealth, we show that top wealth holders are almost exclusively top capital earners, and increasingly fewer are made up of top labor earners; it has become increasingly difficult in recent decades to access top wealth groups with one's labor income only.
Are population-based models advantageous in estimating the lumen outputs from light-pollution sources?
Authors: Kocifaj M , Kómar L , Lamphar H , Wallner S 
Published: May 2020

Abstract
The total lumen output (TLO) from ground-based artificial light sources is required in a wide range of light-pollution models currently in use. No realistic assessment of diffuse light levels in the nocturnal environment is possible if the information on TLO is missing. Traditional approaches to skyglow modelling, if no lighting inventory is available, foresee to estimate TLO based on population and average amount of lumens per capita. However, we show in this letter that a model based on the area of artificially lit surfaces can reduce uncertainties in estimating TLO by 25 per cent for compact urban areas of defined centres and autonomous character and even 50 per cent for diffuse cities with small satellite towns interacting closely with the main city. The new model could be of great significance to the community of light-pollution researchers, especially astronomers, physicists, and modellers who use TLO routinely in light-pollution characterization.
European genetic ancestry associated with risk of childhood ependymoma
Authors: Zhang Chenan , Ostrom Quinn T , Hansen Helen M , Gonzalez-Maya Julio , Hu Donglei , Ziv Elad , Morimoto Libby , de Smith Adam J , Muskens Ivo S , Kline Cassie N , Vaksman Zalman , Hakonarson Hakon , Diskin Sharon J , Kruchko Carol , Barnholtz-Sloan Jill S , Ramaswamy Vijay , Ali-Osman Francis , Bondy Melissa L , Taylor Michael D , Metayer Catherine , Wiemels Joseph L , Walsh Kyle M 
Published: May 2020

AbstractBackgroundEpendymoma is a histologically defined central nervous system tumor most commonly occurring in childhood. Population-level incidence differences by race/ethnicity are observed, with individuals of European ancestry at highest risk. We aimed to determine whether extent of European genetic ancestry is associated with ependymoma risk in US populations.MethodsIn a multi-ethnic study of Californian children (327 cases, 1970 controls), we estimated the proportions of European, African, and Native American ancestry among recently admixed Hispanic and African American subjects and estimated European admixture among non-Hispanic white subjects using genome-wide data. We tested whether genome-wide ancestry differences were associated with ependymoma risk and performed admixture mapping to identify associations with local ancestry. We also evaluated race/ethnicity-stratified ependymoma incidence data from the Central Brain Tumor Registry of the United States (CBTRUS).ResultsCBTRUS data revealed that African American and Native American children have 33% and 36%, respectively, reduced incidence of ependymoma compared with non-Hispanic whites. In genetic analyses, a 20% increase in European ancestry was associated with a 1.31-fold higher odds of ependymoma among self-reported Hispanics and African Americans (95% CI: 1.08–1.59, Pmeta = 6.7 × 10−3). Additionally, eastern European ancestral substructure was associated with increased ependymoma risk in non-Hispanic whites (P = 0.030) and in Hispanics (P = 0.043). Admixture mapping revealed a peak at 20p13 associated with increased local European ancestry, and targeted fine-mapping identified a lead variant at rs6039499 near RSPO4 (odds ratio = 1.99; 95% CI: 1.45–2.73; P = 2.2 × 10−5) but which was not validated in an independent set of posterior fossa type A patients.ConclusionsInterethnic differences in ependymoma risk are recapitulated in the genomic ancestry of ependymoma patients, implicating regions to target in future association studies.