bluuebunny/crossref_metadata_2025_split huggingface dataset:
Random Effects Misspecification Can Have Severe Consequences for Random Effects Inference in Linear Mixed Models
Authors: Hui Francis K. C. , Müller Samuel , Welsh Alan H. 
Published: April 2020

SummaryThere has been considerable and controversial research over the past two decades into how successfully random effects misspecification in mixed models (i.e. assuming normality for the random effects when the true distribution is non‐normal) can be diagnosed and what its impacts are on estimation and inference. However, much of this research has focused on fixed effects inference in generalised linear mixed models. In this article, motivated by the increasing number of applications of mixed models where interest is on the variance components, we study the effects of random effects misspecification on random effects inference in linear mixed models, for which there is considerably less literature. Our findings are surprising and contrary to general belief: for point estimation, maximum likelihood estimation of the variance components under misspecification is consistent, although in finite samples, both the bias and mean squared error can be substantial. For inference, we show through theory and simulation that under misspecification, standard likelihood ratio tests of truly non‐zero variance components can suffer from severely inflated type I errors, and confidence intervals for the variance components can exhibit considerable under coverage. Furthermore, neither of these problems vanish asymptotically with increasing the number of clusters or cluster size. These results have major implications for random effects inference, especially if the true random effects distribution is heavier tailed than the normal. Fortunately, simple graphical and goodness‐of‐fit measures of the random effects predictions appear to have reasonable power at detecting misspecification. We apply linear mixed models to a survey of more than 4 000 high school students within 100 schools and analyse how mathematics achievement scores vary with student attributes and across different schools. The application demonstrates the sensitivity of mixed model inference to the true but unknown random effects distribution.
Use of asthma drugs and prevalence of molar incisor hypomineralization
Authors: Wogelius Pia , Viuff Jakob Hansen , Haubek Dorte 
Published: April 2020

AbstractBackgroundAsthma and molar incisor hypomineralization (MIH) are common diseases among children and have been suspected to be associated with each other.AimTo examine the association between asthma or the use of asthma drugs and the prevalence of MIH.DesignIn a population‐based cross‐sectional study, we recorded MIH in 9‐year‐old children in Aalborg Municipality, Denmark, born in the year 2000. We used a unique 10‐digit civil personal number to link data on MIH to population‐based medical register data. The exposure was inhaled asthma medication from birth date until date of dental examination. The outcome was the overall prevalence of MIH according to use of asthma medication. Odds ratios (OR) of having MIH were adjusted for gender, use of antibiotics and amoxicillin, maternal smoking, pre‐ and perinatal complication, and hospital admissions.ResultsWe examined 1837 children, of which 542 (29.5%) had one or more molar(s) with MIH. The adjusted odds ratio of having MIH was 0.95 (95% CI: 0.60‐1.51) among children with prescriptions of inhaled asthma medication.ConclusionIn this study, where the results have been adjusted for confounding, we found no association between use of inhaled asthma medication and the prevalence of MIH.
Pension scheme fees and charge ratios in 44 countries: A comparative study
Authors: Han Taejin , Stańko Dariusz 
Published: April 2020

AbstractBased on data received from pension supervisory authorities, the article reviews 85 different pension schemes in 44 jurisdictions by looking at fees and charges as well as their legal ceilings and their development since 2014. A key finding is the observed decrease in fees and caps. The article presents jurisdictions according to clusters, i.e. by groups of countries with identical or very similar items already covered by pension fees, and analyses the extent to which various cost and fee elements are covered by fees charged to members. Finally, we calculate charge ratios for each cluster to quantify the impact of fees and charges on pension savings. Occupational defined contribution pension schemes and personal plans linked to employment tend to be much more cost effective than personal schemes that have no direct employment link.
Nickel percolation and coarsening in sintered Li4Ti5O12 anode composite
Authors: Huddleston William , Dynys Frederick , Sehirlioglu Alp 
Published: April 2020

AbstractInherently safe all‐solid‐state lithium‐ion battery anodes with high electronic and ionic conductivity are sought to enable next‐generation electric propulsion systems. In novel architectural concepts, multifunctionality of battery materials will provide simultaneous mechanical load bearing and electrochemical energy storage functionality for systems level mass savings. Co‐processing of strain‐free lithium titanate anode and nickel current collector was explored to provide structural integrity and electrical conductivity for a load‐bearing anode with bulk current collection capability. In this study, the effects of processing conditions on densification, electrical conductivity, and microstructural evolution were characterized for Li4Ti5O12‐Ni (LTO‐Ni) composites. Densification of LTO‐Ni was achieved at 900°C and above, and nickel content had minimal effect on final density compared to sintering temperature and time. Electronic conductivity was modeled by percolation theory, exhibiting a large dependence on nickel content and bulk density. Bulk electrical conductivity greater than 1 S/cm was achieved at volume fractions above the percolation threshold. Modeling of microstructural evolution applied Ostwald ripening theories to describe diffusion governing the growth of average nickel particle size and the change in size distributions. Volume fraction effects resulted in larger average Nickel particle sizes and an activation energy of 1.04 eV was measured for nickel particle coarsening.
Integrated learning communities as a peer support initiative for first year university students
Authors: Spiridon Elena , Kaye Linda K. , Nicolson Rod I. , Ransom Heather J. , Tan Angel J. Y. , Tang Bryan W. X. 
Published: April 2020

AbstractPeer Mentoring schemes tend to be developed as retention strategies, however, they can also serve other purposes (psychosocial or career‐related). However, evidence of the effectiveness of these presents mixed results and less is known about the horizontal peer support schemes which may help students capitalize on existing peer relationships. We developed an integrated learning communities (ILC) peer support scheme, building on the theoretical principles of social identity theory, which we embedded within our existing teaching framework and designed functional activities. Collective activities were undertaken to promote the processes of social identity with the intention that these may foster social and academic integration experiences. This intervention was undertaken with an entire cohort of first year undergraduate psychology students. We conducted semi‐structured interviews with a self‐selected sample of these students (N = 17). Thematic analysis revealed two main themes, each with two sub‐themes. These were: “Divergent Experiences” with the sub‐themes of “dependent on people” and “types of support”, and “Good idea in principle” with the sub‐themes of “Theory ≠ Practice” and “Dependent on student engagement”. Although identifying with a peer group was not transparent in the interviews, the existence of a peer support scheme was perceived positively by students which might explain the success of the newly developed student‐led Psychology Society. Indeed, this Psychology Society can provide a lasting framework for further amplification of the student voice. We conclude that our embedded ILC was both feasible and potentially valuable, but it is crucial for the peer support approach to have transactional significance.
Female mate choice and species recognition between two closely related cichlid fish of Lake Malawi, Metriaclima estherae and M. callainos
Authors: Nyalungu Nonhlanhla P. , Couldridge Vanessa 
Published: April 2020

AbstractCichlids are one of the most diverse and colourful groups of freshwater fishes in the world. Despite much investigation, the factors that promote speciation in these fishes are still uncertain. However, previous studies suggest that sexual selection on male colour is one of the main drivers of speciation among these fishes. Metriaclima estherae is a polymorphic cichlid species from Lake Malawi, and thus provides an ideal model for the investigation of the importance of colour as a species recognition cue. M. callainos is a closely related and morphologically similar species, with male colour pattern very similar to that of M. estherae. We tested female choice by giving females of the two species a choice between conspecific and heterospecific males in the presence and absence of visual (colour) and chemical cues. The results show that females of M. callainos were able to reliably recognize conspecific males, even when colour was eliminated as a cue. However, females of M. estherae did not prefer conspecific males, although they were able to discriminate between red and blue conspecific colour morphs by using chemical cues. These results suggest that species recognition cues may differ even among closely related species of cichlid fish, and that female preferences for male coloration may be weak in certain species.
Assortative aggression among males in a sympatric pair of Labeotropheus from Lake Malaŵi, Africa
Authors: Pauers Michael J. , Grudnowski Jacob A. 
Published: April 2020

AbstractFemale mate choice has strong experimental support as a diversifying force in the speciation of the haplochromine cichlid fishes of Lake Malaŵi, Africa. Somewhat less understood is the role that male–male aggression might have played in the evolution of new species of these fishes. In the rock‐dwelling haplochromines of Lake Malaŵi, primarily territory‐holding males successfully court females; by determining which males gain territories, male–male aggression could support speciation by excluding less‐fit males from the breeding population. To test the hypothesis that males should direct more aggression towards conspecific rivals, the aggression directed towards conspecific and heterospecific opponents was compared in a sympatric pair of cichlids of the genus Labeotropheus Ahl 1927 (Labeotropheus fuelleborni Ahl 1927 and Labeotropheus trewavasae Fryer 1956). It was found that when presented with a pair of rivals, males of both species did direct more aggression towards the conspecific opponent, and the amount of aggression increased when the conspecific opponent was larger than the heterospecific opponent. In addition, this study found a difference in the behavioural repertoire of the species: L. fuelleborni tends to rely on displays to intimidate opponents, whereas L. trewavasae employs more physical attacks to drive away opponents. Males of both species can thus recognize conspecifics and assess an opponent's relative threat to their ability to successfully reproduce, and use species‐specific strategies to intimidate opponents.
Thermal variation near the thermal optimum does not affect the growth, metabolism or swimming performance in wild Atlantic salmonSalmo salar
Authors: Morissette Jenna , Swart Sula , MacCormack Tyson J. , Currie Suzanne , Morash Andrea J. 
Published: April 2020

AbstractTypically, laboratory studies on the physiological effects of temperature are conducted using stable acclimation temperatures. Nonetheless, information extrapolated from these studies may not accurately represent wild populations living in thermally variable environments. The aim of this study was to compare the growth rate, metabolism and swimming performance of wild Atlantic salmon exposed to cycling temperatures, 16–21°C, and stable acclimation temperatures, 16, 18.5, 21°C. Growth rate, metabolic rate, swimming performance and anaerobic metabolites did not change among acclimation groups, suggesting that within Atlantic salmon's thermal optimum range, temperature variation has no effect on these physiological properties.
Identification and characterization of outer membrane vesicles from the fish pathogen Vibrio ordalii
Authors: Echeverría‐Bugueño Macarena , Espinosa‐Lemunao Rodrigo , Irgang Rute , Avendaño‐Herrera Ruben 
Published: April 2020

AbstractVibriosis outbreaks due to Vibrio ordalii occur globally, but Chilean salmon aquaculture, in particular, has suffered significant monetary losses in the last 15 years. Little is known about the virulence mechanisms employed by V. ordalii. However, most Vibrio pathogens (e.g., Vibrio anguillarum, a very close taxonomic species) present outer membrane vesicles (OMVs) that are released extracellularly and implicated in the delivery of virulence factors to host cells. This study provides the first reported evidence of the fish pathogen V. ordalii producing and releasing OMVs under normal growth conditions. Analyses were conducted with the V. ordalii strain Vo‐LM‐18 and the type strain ATCC 33509T. For comparative purposes, the reference strain V. anguillarum ATCC 43307 was employed. The average size for the three Vibrio strains was 0.215 ± 0.6 µm (via scanning electron microscopy) or between 0.19 and 1.8 µm (via dynamic light scattering), with each bacterium presenting a wide range. SDS‐PAGE revealed similarities in OMV patterns, but neither total nor external proteins were identical. Comparing V. ordalii ATCC 33509T and Vo‐LM‐18, bands were most evident in the total proteins, and the greatest degree of similarity in OMV profiles was between 37 and 50 kDa. The purified OMVs demonstrated haemolytic enzyme activity, which could play a role during V. ordalii infection. These data represent an initial step towards gaining new insights into this virulence factor, of which a lot is known in other pathogenic microorganisms.
Fecal calprotectin is a reliable marker of endoscopic response to vedolizumab therapy: A simple algorithm for clinical practice
Authors: Pauwels Renske Wilhelmina Maria , de Vries Annemarie Charlotte , van der Woude Christien Janneke 
Published: April 2020

AbstractBackground and AimThe association of fecal calprotectin (FC) and endoscopic response in inflammatory bowel disease patients during vedolizumab (VDZ) treatment is largely unknown. The aim of this study is to assess the diagnostic value of FC to predict endoscopic response.MethodsPatients with active endoscopic disease at baseline were included. Endoscopies and FC tests were performed at baseline and week 16. Patients with a confirmed endoscopic response at week 16 continued VDZ maintenance therapy, and endoscopy and FC tests were performed at week 52. Endoscopic response was defined as endoscopic Mayo score reduction of ≥ 1, SES‐CD of ≥ 50%, or Rutgeerts' score of ≥ 1. Correlations were assessed using Spearman and receiver operating characteristic statistics.ResultsA total of 114 patients, 46 ulcerative colitis and 68 Crohn's disease patients (44 men, median age 40 years), were included after the start of VDZ; 85% was anti‐tumor necrosis factor alpha refractory. Endoscopic response was observed in 60 (53%) patients at week 16; the response sustained in 73% at week 52. FC decreased significantly from 819 at baseline to 154 μg/g at week 16. FC at weeks 16 and 52 were significantly correlated to (sustained) endoscopic response (r = −0.62 / r = −0.67, P < 0.001). FC < 200 μg/g indicates endoscopic response (area under the curve = 0.89, positive predictive value = 94%), whereas FC > 450 μg/g indicates endoscopic non‐response after induction (negative predictive value = 83%). An increase in FC level of > 400 μg/g after induction indicates endoscopic loss of response (area under the curve = 0.97, negative predictive value = 96%).ConclusionThis prospective study demonstrates a significant correlation between FC and endoscopic response to VDZ. FC < 200 μg/g prognosticate endoscopic response, and FC > 450 μg/g endoscopic non‐response. An increase in FC of > 400 μg/g after induction indicates endoscopic loss of response. This simple FC algorithm may guide clinical decisions on the continuation and optimization of VDZ in inflammatory bowel disease patients.
Fecal calprotectin and need of multiple microbiota trasplantation infusions in Clostridium difficile infection
Authors: Gallo Antonella , Cancelli Cristina , Ceron Emily , Covino Marcello , Capoluongo Ettore , Pocino Krizia , Ianiro Gianluca , Cammarota Giovanni , Gasbarrini Antonio , Montalto Massimo 
Published: April 2020

AbstractBackground and AimFecal microbiota transplantation (FMT) has proven to be very effective in recurrent Clostridium difficile infection (CDI) when compared with standard antibiotic therapy. However, given the lack of validated criteria, decision regarding number and timing of infusions is currently based on the clinician's experience, severity of infection, and clinical response. We performed a longitudinal assessment of fecal calprotectin concentration (FCC) in CDI patients undergoing FMT. FCCs were correlated with the need for multiple infusions and with the clinical status of the patient.MethodsFecal calprotectin concentration measurement was performed just before first procedure (T0) and 2 (T1) and 5 (T2) days later. The need for reinfusion was accounted for in the 8 weeks following procedure, and clinical status was evaluated at the end of the given period. Both outcomes were correlated with measured FCCs.ResultsA total of 28 CDI patients undergoing FMT were enrolled. Median FCCs at T0 were significantly higher in patients who needed repeat FMT, 540 μg/g versus patients who underwent single FMT, 290 μg/g (P < 0.05). Differences were not significant for FCC at T1 and T2. Regarding correlation with clinical outcome, median FCC at T0 was found to be lower in responders compared with non‐responders with a trend towards statistical significance (P = 0.07). Correlation at T1 and T2 was not significant.ConclusionsThe use of an easily obtainable parameter such as fecal calprotectin could possibly optimize overall management of FMT procedural framework potentially being able to immediately identify patients who may benefit from repeat infusions.
Cancer, hear my battle CRY
Authors: Chan Alanna B. , Lamia Katja A. 
Published: April 2020

AbstractCircadian clocks are cell‐autonomous self‐sustaining oscillators that allow organisms to anticipate environmental changes throughout the solar day and persist in nearly every cell examined. Environmental or genetic disruption of circadian rhythms increases the risk of several types of cancer, but the underlying mechanisms are not well understood. Here, we discuss evidence connecting circadian rhythms—with emphasis on the cryptochrome proteins (CRY1/2)—to cancer through in vivo models, mechanisms involving known tumor suppressors and oncogenes, chemotherapeutic efficacy, and human cancer risk.
Spatial phylogenetics of the North American flora
Authors: Mishler Brent D. , Guralnick Robert , Soltis Pamela S. , Smith Stephen A. , Soltis Douglas E. , Barve Narayani , Allen Julie M. , Laffan Shawn W. 
Published: April 2020

AbstractNorth America is a large continent with extensive climatic, geological, soil, and biological diversity. As biota faces threat from habitat destruction and climate change, making a quantitative assessment of biodiversity becomes critically important. Rapid digitization of plant specimen records and accumulation of DNA sequence data enable a much‐needed broad synthesis of species occurrences with phylogenetic data. In this study, the first such synthesis of a flora from such a large and diverse part of the world is attempted, all seed plants from the North American continent (here defined to include Canada, United States, and Mexico), with a focus on examining phylogenetic diversity and endemism. We collected digitized plant specimen records and chose a coarse grain for analysis, recognizing that this grain is currently necessary for reasonable completeness per sampling unit. We found that raw richness and endemism patterns largely support previous hypotheses of biodiversity hotspots. The application of phylogenetic metrics and a randomization test revealed novel results, including a significant phylogenetic clustering across the continent, a striking east–west geographical difference in the distribution of branch lengths, and the discovery of centers of neo‐ and paleoendemism in Mexico, the southwestern USA, and the southeastern USA. Finally, our examination of phylogenetic beta diversity provides a new approach to compare centers of endemism. We discuss the empirical challenges of working at the continental scale and the need for more sampling across large parts of the continent, for both DNA data for terminal taxa and spatial data for poorly understood regions, to confirm and extend these results.
The role of weighing‐bathing sequence and postmenstrual age in eliciting adaptive/maladaptive responses in very low birth weight preterm infants
Authors: Bembich Stefano , Trappan Antonella , Galimberti Alice , Taglieri Jessica , Scolz Sabrina , Risso Francesco Maria , Sanson Gianfranco 
Published: April 2020

AbstractPurposeIn the neonatal intensive care unit, preterm infants are exposed to several stressful stimuli. Inappropriate stimulation led to high risk for short‐ and long‐term neurocognitive disabilities. This study aimed to evaluate whether the sequence of execution of weighing/bathing nursing procedures and postmenstrual age (PMA) have any effect on preterm infants' stress responses.Design and MethodsProspective cross‐sectional study on a sample of 21 preterm infants. Responses to the procedures were assessed using an observational sheet based on Als's Synactive Theory of Development. Autonomic and motor responses were scored according to five‐point Likert scales. The order of execution of weighing/bathing nursing procedures and PMA were documented. Effects of weighing/bathing execution sequence and PMA on autonomic and motor response scores were analyzed by linear multiple regression analysis.ResultsThe sequence of execution had a significant effect on the autonomic score during weighing (p = .035), evidencing more stress when weighing was executed first. A higher level of stress response on the autonomic score during both weighing (p = .015) and bathing (p = .018) procedure was independently associated with a lower infant PMA.Conclusions and Practice ImplicationsThe real‐time recognition of adaptive/maladaptive responses allows nurses to personalize their approach to preterm infants, taking into account PMA and adjusting the appropriate sequence of execution of weighing/bathing nursing procedures.