bluuebunny/crossref_metadata_2025 huggingface dataset:
The Schizosaccharomyces pombe cdt2+ Gene, a Target of G1-S Phase-Specific Transcription Factor Complex DSC1, Is Required for Mitotic and Premeiotic DNA Replication
Authors: Yoshida Shu-hei , Al-Amodi Hiba , Nakamura Taro , McInerny Christopher J , Shimoda Chikashi
Published: April 2021

We have defined five sev genes by genetic analysis of Schizosaccharomyces pombe mutants, which are defective in both proliferation and sporulation. sev1+/cdt2+ was transcribed during the G1-S phase of the mitotic cell cycle, as well as during the premeiotic S phase. The mitotic expression of cdt2+ was regulated by the MCB-DSC1 system. A mutant of a component of DSC1 affected cdt2+ expression in vivo, and a cdt2+ promoter fragment containing MCB motifs bound DSC1 in vitro. Cdt2 protein also accumulated in S phase and localized to the nucleus. cdt2 null mutants grew slowly at 30° and were unable to grow at 19°. These cdt2 mutants were also medially sensitive to hydroxyurea, camptothecin, and 4-nitroquinoline-1-oxide and were synthetically lethal in combination with DNA replication checkpoint mutations. Flow cytometry analysis and pulsed-field gel electrophoresis revealed that S-phase progression was severely retarded in cdt2 mutants, especially at low temperatures. Under sporulation conditions, premeiotic DNA replication was impaired with meiosis I blocked. Furthermore, overexpression of suc22+, a ribonucleotide reductase gene, fully complemented the sporulation defect of cdt2 mutants and alleviated their growth defect at 19°. These observations suggest that cdt2+ plays an important role in DNA replication in both the mitotic and the meiotic life cycles of fission yeast.
Identification of Quantitative Trait Loci Influencing Wood Property Traits in Loblolly Pine (Pinus taeda L.). III. QTL Verification and Candidate Gene Mapping
Authors: Brown Garth R , Bassoni Daniel L , Gill Geoffrey P , Fontana Joseph R , Wheeler Nicholas C , Megraw Robert A , Davis Mark F , Sewell Mitchell M , Tuskan Gerald A , Neale David B
Published: April 2021

A long-term series of experiments to map QTL influencing wood property traits in loblolly pine has been completed. These experiments were designed to identify and subsequently verify QTL in multiple genetic backgrounds, environments, and growing seasons. Verification of QTL is necessary to substantiate a biological basis for observed marker-trait associations, to provide precise estimates of the magnitude of QTL effects, and to predict QTL expression at a given age or in a particular environment. Verification was based on the repeated detection of QTL among populations, as well as among multiple growing seasons for each population. Temporal stability of QTL was moderate, with approximately half being detected in multiple seasons. Fewer QTL were common to different populations, but the results are nonetheless encouraging for restricted applications of marker-assisted selection. QTL from larger populations accounted for less phenotypic variation than QTL detected in smaller populations, emphasizing the need for experiments employing much larger families. Additionally, 18 candidate genes related to lignin biosynthesis and cell wall structure were mapped genetically. Several candidate genes colocated with wood property QTL; however, these relationships must be verified in future experiments.
Schizosaccharomyces pombe Ras1 Effector, Scd1, Interacts With Klp5 and Klp6 Kinesins to Mediate Cytokinesis
Authors: Li Yingchun , Chang Eric C
Published: April 2021

Fission yeast Scd1 is an exchange factor for Cdc42 and an effector of Ras1. In a screen for scd1 interacting genes, we isolated klp5 and klp6, which encode presumptive kinesins. Klp5 and Klp6 form a complex to control the same processes, which so far include microtubule dynamics and chromosome segregation. We showed that klp5 or klp6 inactivation in combination with the scd1 deletion (scd1Δ) created a synthetic temperature-dependent growth defect. Further genetic analysis demonstrated that Klp5 and Klp6 interacted specifically with the Ras1-Scd1 pathway, but not with the Ras1-Byr2 pathway. In addition, Klp5 and Klp6 can stably associate with Scd1 and Cdc42. A deletion in the Scd1 C terminus, which contains the PB1 domain, prevented Scd1 binding to Klp5/6 and caused a growth defect in Klp5/6 mutant cells that is indistinguishable from that induced by scd1Δ. Analysis of the double-mutant phenotype indicated that at the nonpermissive temperature, cells failed to undergo cytokinesis efficiently. These cells contained abnormal contractile rings in which F-actin and Mid1, a key regulator of F-actin ring formation and positioning, are mispositioned and fragmented. These data suggest that Klp5/6 cooperate with the Ras1-Scd1 pathway to influence proper formation of the contractile ring for cytokinesis.
A Novel Step in β-Tubulin Folding Is Important for Heterodimer Formation in Saccharomyces cerevisiae
Authors: Lacefield Soni , Solomon Frank
Published: April 2021

Undimerized β-tubulin is toxic in the yeast S. cerevisiae. It can arise if levels of β-tubulin and α-tubulin are unbalanced or if the tubulin heterodimer dissociates. We are using the toxicity of β-tubulin to understand early steps in microtubule morphogenesis. We find that deletion of PLP1 suppresses toxic β-tubulin formed by disparate levels of α- and β-tubulin. That suppression occurs either when α-tubulin is modestly underexpressed relative to β-tubulin or when β-tubulin is inducibly and strongly overexpressed. Plp1p does not affect tubulin expression. Instead, a significant proportion of the undimerized β-tubulin in plp1Δ cells is less toxic than that in wild-type cells. It is also less able to combine with α-tubulin to form a heterodimer. As a result, plp1Δ cells have lower levels of heterodimer. Importantly, plp1Δ cells that also lack Pac10, a component of the GimC/PFD complex, are even less affected by free β-tubulin. Our results suggest that Plp1p defines a novel early step in β-tubulin folding.
A Bacterial Genetic Screen Identifies Functional Coding Sequences of the InsectmarinerTransposable ElementFamar1Amplified From the Genome of the Earwig,Forficula auricularia
Authors: Barry Elizabeth G , Witherspoon David J , Lampe David J
Published: April 2021

Transposons of the mariner family are widespread in animal genomes and have apparently infected them by horizontal transfer. Most species carry only old defective copies of particular mariner transposons that have diverged greatly from their active horizontally transferred ancestor, while a few contain young, very similar, and active copies. We report here the use of a whole-genome screen in bacteria to isolate somewhat diverged Famar1 copies from the European earwig, Forficula auricularia, that encode functional transposases. Functional and nonfunctional coding sequences of Famar1 and nonfunctional copies of Ammar1 from the European honey bee, Apis mellifera, were sequenced to examine their molecular evolution. No selection for sequence conservation was detected in any clade of a tree derived from these sequences, not even on branches leading to functional copies. This agrees with the current model for mariner transposon evolution that expects neutral evolution within particular hosts, with selection for function occurring only upon horizontal transfer to a new host. Our results further suggest that mariners are not finely tuned genetic entities and that a greater amount of sequence diversification than had previously been appreciated can occur in functional copies in a single host lineage. Finally, this method of isolating active copies can be used to isolate other novel active transposons without resorting to reconstruction of ancestral sequences.
Differential Segregation Patterns of Sperm Mitochondria in Embryos of the Blue Mussel (Mytilus edulis)
Authors: Cao Liqin , Kenchington Ellen , Zouros Eleftherios
Published: April 2021

In Mytilus, females carry predominantly maternal mitochondrial DNA (mtDNA) but males carry maternal mtDNA in their somatic tissues and paternal mtDNA in their gonads. This phenomenon, known as doubly uniparental inheritance (DUI) of mtDNA, presents a major departure from the uniparental transmission of organelle genomes. Eggs of Mytilus edulis from females that produce exclusively daughters and from females that produce mostly sons were fertilized with sperm stained with MitoTracker Green FM, allowing observation of sperm mitochondria in the embryo by epifluorescent and confocal microscopy. In embryos from females that produce only daughters, sperm mitochondria are randomly dispersed among blastomeres. In embryos from females that produce mostly sons, sperm mitochondria tend to aggregate and end up in one blastomere in the two- and four-cell stages. We postulate that the aggregate eventually ends up in the first germ cells, thus accounting for the presence of paternal mtDNA in the male gonad. This is the first evidence for different behaviors of sperm mitochondria in developing embryos that may explain the tight linkage between gender and inheritance of paternal mitochondrial DNA in species with DUI.
Meiotic Recombination Between Paralogous RBCSB Genes on Sister Chromatids of Arabidopsis thaliana
Authors: Jelesko John G , Carter Kristy , Thompson Whitney , Kinoshita Yuki , Gruissem Wilhelm
Published: April 2021

Paralogous genes organized as a gene cluster can rapidly evolve by recombination between misaligned paralogs during meiosis, leading to duplications, deletions, and novel chimeric genes. To model unequal recombination within a specific gene cluster, we utilized a synthetic RBCSB gene cluster to isolate recombinant chimeric genes resulting from meiotic recombination between paralogous genes on sister chromatids. Several F1 populations hemizygous for the synthRBCSB1 gene cluster gave rise to Luc+ F2 plants at frequencies ranging from 1 to 3 × 10-6. A nonuniform distribution of recombination resolution sites resulted in the biased formation of recombinant RBCS3B/1B::LUC genes with nonchimeric exons. The positioning of approximately half of the mapped resolution sites was effectively modeled by the fractional length of identical DNA sequences. In contrast, the other mapped resolution sites fit an alternative model in which recombination resolution was stimulated by an abrupt transition from a region of relatively high sequence similarity to a region of low sequence similarity. Thus, unequal recombination between paralogous RBCSB genes on sister chromatids created an allelic series of novel chimeric genes that effectively resulted in the diversification rather than the homogenization of the synthRBCSB1 gene cluster.
Chromosome Instabilities and Programmed Cell Death in Tapetal Cells of Maize With B Chromosomes and Effects on Pollen Viability
Authors: González-Sánchez Mónica , Rosato Marcela , Chiavarino Mauricio , Puertas María J
Published: April 2021

B chromosomes (B’s), knobbed chromosomes, and chromosome 6 (NOR) of maize undergo nondisjunction and micronucleus formation in binucleate tapetal cells. These chromosome instabilities are regular events in the program of tapetal cell death, but the B’s strongly increase A chromosome instability. We studied 1B and 0B plants belonging to selected lines for high or low B transmission rate and their F1 hybrids. These lines are characterized by meiotic conservation or loss of B chromosomes, respectively. The female B transmission (fBtl) allele(s) for low B transmission is dominant, inducing micronucleus formation and B nondisjunction. We hypothesize that the fBtl allele(s) induces knob instability. This instability would be sufficient to produce B loss in both meiocytes and binucleate tapetal cells. B instability could, in turn, produce instabilities in all chromosomes of maize complement. To establish whether the chromosomal instabilities are related to the tapetal programmed cell death (PCD) process, we applied the TUNEL technique. PCD, estimated as the frequency of binucleate tapetal cells with TUNEL label, was significantly correlated with the formation of micronuclei and the frequency of pollen abortion. It can be concluded that the observed chromosome instabilities are important to the PCD process and to the development of microspores to form viable pollen grains.
The Evolution of the Drosophila Sex-Determination Pathway
Authors: Pomiankowski Andrew , Nöthiger Rolf , Wilkins Adam
Published: April 2021

The molecular complexity of the Drosophila somatic sex-determination pathway poses formidable intellectual challenges for attempts to explain its evolutionary origins. Here we present a reconstruction of how this regulatory cascade might have evolved in a step-by-step fashion. We illustrate how mutations in genes, which were already part of the pathway or were recruited as new regulators of the pathway, were favored by sexual selection acting on the discriminatory sex-determining signal. This allows us to explain the major features of the pathway, including multiple promoter sites, alternative splicing patterns, autoregulation, and stop codons. Our hypothesis is built on the available data from Drosophila and other insect species, and we point out where it is amenable to further experimental and comparative tests.
Time-lapse resistivity imaging: CSEM-data 3-D double-difference inversion and application to the Reykjanes geothermal field
Authors: Bretaudeau F , Dubois F , Bissavetsy Kassa S-G , Coppo N , Wawrzyniak P , Darnet M
Published: April 2021

Time-lapse resistivity tomography bring valuable information on the physical changes occurring inside a geological reservoir. In this study, resistivity monitoring from controlled source electromagnetics (CSEM) data is investigated through synthetic and real data. We present three different schemes currently used to perform time-lapse inversions and compare these three methods: parallel, sequential and double difference. We demonstrate on synthetic tests that double difference scheme is the best way to perform time-lapse inversion when the survey parameters are fixed between the different time-lapse acquisitions. We show that double difference inversion allows to remove the imprint of correlated noise distortions, static shifts and most of the non-linearity of the inversion process including numerical noise and acquisition footprint. It also appears that this approach is robust against the baseline resistivity model quality, and even a rough starting resistivity model built from borehole logs or basic geological knowledge can be sufficient to map the time-lapse changes at their right positions. We perform these comparisons with real land time-lapse CSEM data acquired one year apart over the Reykjanes geothermal field.
“Notorious RBG”: A conversation with United States Supreme Court Justice Ruth Bader Ginsburg
Authors: Rubio-Marín Ruth
Published: April 2021

On February 2, 2016, Prof. Ruth Rubio-Marín, Chair of Constitutional and Comparative Public Law at the European University Institute (EUI), interviewed the U.S. Supreme Court Associate Justice Ruth Bader Ginsburg. The interview took place in the framework of the European University Institute’s annual Ursula Hirschmann Lecture, a space dedicated to stimulate research and thinking which links ideas about Europe and the study of gender. Justice Ruth Bader Ginsburg engaged in a conversation that tackled her whole persona, without making rigid divides between the professional and the personal. Deep legal analysis, personal anecdotes, and invaluable advice for future researchers and lawyers intertwine in the interview, which sheds light on important dimensions of equality law.
Patient-reported outcome measurement of symptom distress is feasible in most clinical scenarios in palliative care: an observational study involving routinely collected data
Authors: Clapham Sabina , Daveson Barbara A , Allingham Samuel F , Morris Darcy , Blackburn Pippa , Johnson Claire E , Eagar Kathy
Published: April 2021

Background

Implementation of routinely collected patient-reported outcome measures (PROMs) ensures patients’ priorities are at the forefront of care planning and helps to standardize approaches to quality improvement. In palliative care, barriers to PROMs are widely known but what are not understood are the clinical and care settings in which patients are more likely to report and when proxy reporting is needed.

Objective

To examine the incidence of patient-reported symptom distress compared to the incidence of proxy reporting in palliative care and influencing factors.

Methods

A national observational study using routinely collected PROMs data with influencing factors investigated by logistic regression modelling. Participants were patients with an advanced life-limiting illness receiving palliative care in an inpatient or a community healthcare setting in Australia.

Results

Sixteen thousand one hundred and fifty-eight reports of symptom distress were collected from 1117 patients seen by 21 palliative care services. The majority of respondents were diagnosed with cancer (76%), were older (≥65 years, 72%) and had nominated English as their first language (88%). The majority of symptom distress reports were completed by patients (61%). The odds of a patient providing a self-report where grater when they were receiving community versus inpatient palliative care (odds ratio (OR): 3.0; 95% confidence interval (CI): 2.25–4.01), for patients diagnosed with malignant versus non-malignant disease (OR 1.7; 95% CI: 1.26–2.31), and for those who required an urgent change in their care plan versus those whose symptoms and problems were adequately managed (OR: 1.38; 95% CI: 1.04–1.83).

Conclusion

Three factors are associated with an increased likelihood of patient versus proxy reporting in palliative care: healthcare setting, diagnosis, and the acuity and urgency of the patient’s clinical needs. PROMs are feasible in most clinical scenarios in palliative care, including when an urgent clinical response is required.
Pharmacokinetic/pharmacodynamic evaluation of tobramycin dosing in critically ill patients: the Hartford nomogram does not fit
Authors: Xie Feifan , Wang Yan , Peng Yaru , Cheng Zeneng , Li Sanwang
Published: April 2021

Objectives

Extended-interval dosing of tobramycin is widely applied in patients with the Hartford nomogram as a representative, while this dosing approach has not been extensively evaluated in critically ill patients. The goal of this study was to characterize the pharmacokinetics of tobramycin and to evaluate the appropriateness of the Hartford nomogram in critically ill patients.

Methods

A retrospective analysis was performed based on a medical critical care database. The extracted concentration data of tobramycin were used for the construction of the population pharmacokinetic model using a non-linear mixed-effects modelling approach. Real-world data-based simulations were conducted to evaluate the pharmacodynamic target attainment (Cmax/MIC ≥10) and safety (concentration <0.5 mg/L for at least 4 h) of the Hartford nomogram.

Results

A population pharmacokinetic model was built based on 307 measurements in 140 unique patients and externally validated by an independent study dataset. A two-compartment model was optimal for the structure model and creatinine clearance remained as the only covariate in the final model correlating to the clearance of tobramycin. Simulations indicated that the Hartford nomogram is effective for infections due to pathogens with an MIC of ≤1 mg/L, but not with an MIC of 2 mg/L. The percentage of patients who reached the non-toxicity target was quite low under the Hartford nomogram and a further extension of the dosing interval was necessary to minimize the toxicity.

Conclusions

The Hartford nomogram was not suitable for critically ill patients with pathogen MICs of 2 mg/L and drug monitoring is required to manage efficacy and toxicity.
Cross-Lag Model of Medical Responsibility and Skills in Youth With Spina Bifida
Authors: Smith Zoe R , Holmbeck Grayson N
Published: April 2021

Objective

This study examined bidirectional associations between mother- and father-reported medical responsibility and medical skill mastery in youth with spina bifida (SB).

Methods

Participants were 140 youth with SB and their parents who participated in three waves of a longitudinal study across four years (ages 8–15 years at Time 1). Mother- and father-report of both medical responsibility and medical skill mastery were used, and age and estimated intelligence quotient were included as covariates, in cross-lagged models.

Results

The cross-lagged model provided evidence for significant bidirectional associations between mother-reported medical responsibility and skill mastery across time (root mean square error of approximation=0.09, comparative fix index=0.97). These paths showed that higher levels of child responsibility predicted an increase in skill mastery and that higher levels of mastery predicted an increase in child responsibility across time. Moreover, based on mother-report, sharing of responsibility had stronger effects on increases in skill mastery (Time 1 to Time 2 β=.25, Time 2 to Time 3 β=.27) than skill mastery had on increases in child responsibility (Time 1 to Time 2 β=.08, Time 2 to Time 3 β=.07). The only significant cross-lagged path for father-report was from Time 1 skill mastery to Time 2 responsibility (β=.34).

Conclusions

Mothers perceive a bidirectional relationship between responsibility and skill mastery across time, whereas fathers appear to mainly consider how skills might affect a subsequent increase in responsibility sharing. Thus, it is important to consider both parents’ perspectives when working to increase medical autonomy in youth with SB.
Storytelling in Research with Refugees: On the Promise and Politics of Audibility and Visibility in Participatory Research in Contexts of Forced Migration
Authors: Saltsman Adam , Majidi Nassim
Published: April 2021

Researchers' methodological decisions have an impact on who gets to hear a refugees' story, the meaning a story conveys, and, consequently, the implications a story might have for forced migrants. What we as researchers, or aid workers, do with the stories gathered from forced migrants can contribute to their social and political invisibility, or our scholarship can be a tool to amplify refugee voices as forms of knowledge that are valid not only as testimony but as expertise to design research, programmes and policies. What potential do such methods have to disrupt the “established regimes” of what is audible, visible, or legible in society (Rancière, 2010)? In response to what is now widespread recognition of the “dual imperative” in forced migration research (Jacobsen and Landau 2003), action research has emerged as a common way to do research that is useful to the communities with which we engage. In this article we reflect on our efforts as researchers to address power imbalances by placing forced migrant stories at the forefront of our methods. We rely on two case studies to provide insights into and learn from critical narratives from the displaced themselves: 1) at the Thai-Burmese border, 2) with Somali refugee returnees in Kismayo. The two case studies reveal different ways of working with stories and strategies that can help address the inaudibility of refugee stories. We recognize that such work is necessarily partial and ongoing. To identify space for continued growth and learning, we point to moments where collaboration faltered and moments where our research inadvertently reproduced power inequities.
Massive congenital cervicofacial desmoid-type fibromatosis in a 5-month-old infant
Authors: Albokashy Mohammed S , Halawani Mohammed S , Eshky Anoof T , Alsaad Khalid , Khoja Hatim A , Bawazir Samir M
Published: April 2021

Desmoid-type fibromatosis (DF) is a borderline tumor of soft tissues that has low malignant potential but described as infiltrative, locally aggressive and rapidly growing. In the pediatric population, it occurs in the head and neck. Presentation varies based on tumor size and location. Despite the high recurrence rate, surgical excision remains the modality of choice with. Here, we report a case of a 5-month-old boy, with extensive head and neck DF that was managed twice with conservative debulking surgery through a combined transoral-transcervical approach. On 2-year follow-up, he was gaining weight with no developmental delay and had no clinical evidence tumor regrowth.
How to See Corruption: Networks and the Construction of Corruption in Spanish Italy
Authors: Murillo Raphael
Published: April 2021

This article examines the practices and structures of corruption in Spanish Italy and demonstrates how the forms of official conduct that would later be categorized as corrupt in eighteenth-century political and legal discourses were already understood and prosecuted as corruption in the sixteenth and seventeenth centuries, through the intervention at the local level of the visita, an institution employed by the Spanish Crown to inspect officials. The notion of corruption that was useful to the state amalgamated forms of conduct corresponding to distinctive configurations of social structures that functioned like networks. This article examines for the first time the rich collection of depositions assembled by the visitas in Naples and Sicily in 1559, 1581, and 1606, and reproduces four networks of corruption. Through the use of network analysis, these networks point to two foundational structural models of early modern corruption in which officials participated at the local level: a corrupt clientelism typified by relationships of exchange and favor organized by officials and a corruption of partiality and abuse of discretion embedded within institutional work and processes. Although distinct, these models were conceptually linked through the perception that these networks benefitted particular interests and were critically drawn together through the surveillance and discipline provided by the visita in anticipation of anti-corruption ideology and modern bureaucratic norms. What the state saw through the visita and prosecuted as corrupt reflected how that corruption was reported, how it occurred, and how it was structured.
Evaluation of a Field-Ready Neurofunctional Assessment Tool for Use in a Military Environment
Authors: Tommerdahl Mark , Favarov Oleg , Wagner Christina D , Walilko Timothy J , Zai Laila , Bentley Timothy B
Published: April 2021

Introduction

The Office of Naval Research sponsored the Blast Load Assessment Sense and Test (BLAST) program to develop a rapid, in-field solution that could be used by team leaders, commanders, and medical personnel to provide a standardized approach to operationally relevant monitoring and analysis of service members exposed to single or repeated low-level blast. A critical piece of the BLAST team’s solution was the development of the Brain Gauge technology which includes a cognitive assessment device that measures neurofunctional changes by testing sensory perceptions and a suite of mathematical algorithms that analyze the results of the test. The most recent versions of the technology are easily portable; the device is in the size and shape of a computer mouse. Tests can be administered in a matter of minutes and do not require oversight by a clinician, making Brain Gauge an excellent choice for field use. This paper describes the theoretical underpinnings and performance of a fieldable Brain Gauge technology for use with military populations.

Materials and Methods

The methods used by the Brain Gauge have been documented in over 80 peer-reviewed publications. These papers are reviewed, and the utility of the Brain Gauge is described in terms of those publications.

Results

The Brain Gauge has been demonstrated to be an effective tool for assessing blast-induced neurotrauma and tracking its recovery. Additionally, the method parallels neurophysiological findings of animal models which provide insight into the sensitivity of specific metrics to mechanisms of information processing.

Conclusions

The overall objective of the work was to provide an efficient tool, or tools, that can be effectively used for (1) determining stand-down criteria when critical levels of blast exposure have been reached and (2) tracking the brain health history until return-to-duty status is achieved. Neurofunctional outcome measures will provide the scientific link between blast sensors and the impact of blast on biological health. This calibration process is strengthened with outcome measures that have a biological basis that are paralleled in animal models. The integrative approach that utilizes the Brain Gauge technology will provide a significant advance for assessing the impact of blast exposure and support rapid, science-based decision-making that will ensure mission success and promote the protection of brain health in service members.
The detectability of binary star planetary and brown dwarf companions from eclipse timing variations
Authors: Getley A K , Carter B , King R , O’Toole S
Published: April 2021

In this paper, we determine the detectability of eclipsing binary star companions from eclipse timing variations using the Kepler mission data set. Extensive and precise stellar time-series photometry from space-based missions enable searches for binary star companions. However, due to the large data sets and computational resources involved, these searches would benefit from guidance from detection simulations. Our simulations start with and benefit from the use of empirical Kepler mission data, into which we inject third bodies to predict the resulting timing of binary star eclipses. We find that the orbital eccentricity of the third body and the orbital period of the host binary star are the key factors in detecting companions. Target brightness is also likely to be a factor in detecting companions. Detectable third body masses and periods can be efficiently bound using just two equations. Our results enable the setting of realistic expectations when planning searches for eclipsing binary star planetary and brown dwarf companions. Our results also suggest the brown dwarf desert is real rather than observational selection.
Spectroscopic quantification of projection effects in the SDSS redMaPPer galaxy cluster catalogue
Authors: Myles J , Gruen D , Mantz A B , Allen S W , Morris R G , Rykoff E , Costanzi M , To C , DeRose J , Wechsler R H , Rozo E , Jeltema T , Carrasco E R , Kremin A , Kron R
Published: April 2021

Projection effects, whereby galaxies along the line of sight to a galaxy cluster are mistakenly associated with the cluster halo, present a significant challenge for optical cluster cosmology. We use statistically representative spectral coverage of luminous galaxies to investigate how projection effects impact the low-redshift limit of the Sloan Digital Sky Survey (SDSS) redMaPPer galaxy cluster catalogue. Spectroscopic redshifts enable us to differentiate true cluster members from false positives and determine the fraction of candidate cluster members viewed in projection. Our main results can be summarized as follows: first, we show that a simple double-Gaussian model can be used to describe the distribution of line-of-sight velocities in the redMaPPer sample; secondly, the incidence of projection effects is substantial, accounting for ∼16 per cent of the weighted richness for the lowest richness objects; thirdly, projection effects are a strong function of richness, with the contribution in the highest richness bin being several times smaller than for low-richness objects; fourthly, our measurement has a similar amplitude to state-of-the-art models, but finds a steeper dependence of projection effects on richness than these models; and fifthly, the slope of the observed velocity dispersion–richness relation, corrected for projection effects, implies an approximately linear relationship between the true, three-dimensional halo mass and three-dimensional richness. Our results provide a robust, empirical description of the impact of projection effects on the SDSS redMaPPer cluster sample and exemplify the synergies between optical imaging and spectroscopic data for studies of galaxy cluster astrophysics and cosmology.
Explaining the scatter in the galaxy mass–metallicity relation with gas flows
Authors: van Loon Maria L , Mitchell Peter D , Schaye Joop
Published: April 2021

The physical origin of the scatter in the relation between galaxy stellar mass and the metallicity of the interstellar medium, i.e. the mass–metallicity relation (MZR), reflects the relative importance of key processes in galaxy evolution. The eagle cosmological hydrodynamical simulation is used to investigate the correlations between the residuals of the MZR and the residuals of the relations between stellar mass and, respectively, specific inflow, outflow, and star formation rate as well as the gas fraction for central galaxies. At low redshift, all these residuals are found to be anticorrelated with the residuals of the MZR for M⋆/M⊙ ≲ 1010. The correlations between the residuals of the MZR and the residuals of the other relations with mass are interrelated, but we find that gas fraction, specific inflow rate, and specific outflow rate all have at least some independent influence on the scatter of the MZR. We find that, while for M⋆/M⊙ > 1010.4 the specific mass of the nuclear black hole is most important, for M⋆/M⊙ ≲ 1010.3 gas fraction and specific inflow rate are the variables that correlate most strongly with the MZR scatter. The time-scales involved in the residual correlations and the time that galaxies stay above the MZR are revealed to be a few Gyr. However, most galaxies that are below the MZR at z = 0 have been below the MZR throughout their lifetimes.
Linking computational models to follow the evolution of heated coronal plasma
Authors: Reid J , Cargill P J , Johnston C D , Hood A W
Published: April 2021

A ‘proof of principle’ is presented, whereby the Ohmic and viscous heating determined by a three-dimensional (3D) MHD model of a coronal avalanche are used as the coronal heating input for a series of field-aligned, one-dimensional (1D) hydrodynamic models. Three-dimensional coronal MHD models require large computational resources. For current numerical parameters, it is difficult to model both the magnetic field evolution and the energy transport along field lines for coronal temperatures much hotter than $1\, \mathrm{MK}$, because of severe constraints on the time step from parallel thermal conduction. Using the 3D MHD heating derived from a simulation and evaluated on a single field line, the 1D models give coronal temperatures of $1\, \mathrm{MK}$ and densities $10^{14}\textrm {--}10^{15}\, \mathrm{m}^{-3}$ for a coronal loop length of $80\, \mathrm{Mm}$. While the temperatures and densities vary smoothly along the field lines, the heating function leads to strong asymmetries in the plasma flows. The magnitudes of the velocities in the 1D model are comparable with those seen in 3D reconnection jets in our earlier work. Advantages and drawbacks of this approach for coronal modelling are discussed.
A revisited study of Cepheids in open clusters in the Gaia era
Authors: Medina Gustavo E , Lemasle Bertrand , Grebel Eva K
Published: April 2021

In this paper, we revisit the problem of identifying bona fide cluster Cepheids by performing an all-sky search for Cepheids associated with open clusters and making use of state-of-the-art catalogued information for both Cepheids and clusters, based on the unparalleled astrometric precision of the second and early third data releases of the Gaia satellite. We determine membership probabilities by following a Bayesian approach using spatial and kinematic information of the potential cluster-Cepheid pairs. We confirm 19 Cepheid-cluster associations considered in previous studies as bona fide, and question the established cluster membership of six other associations. In addition, we identify 138 cluster Cepheid candidates of potential interest, mostly in recently discovered open clusters. We report on at least two new clusters possibly hosting more than one Cepheid. Furthermore, we explore the feasibility of using open clusters hosting Cepheids to empirically determine the Cepheid period–age relation through the use of Gaia and 2MASS photometry and a semiautomated method to derive cluster ages. We conclude that the usage of cluster Cepheids as tentative probes of the period–age relations still faces difficulties due to the sparsely populated red giant branch and the stochastically sampled main-sequence turn-off of the open clusters, making age determinations a challenging task. This biases the age-datable cluster selection for Cepheid period-age studies towards older and high-mass clusters.
Beyond small molecules: targeting G-quadruplex structures with oligonucleotides and their analogues
Authors: Cadoni Enrico , De Paepe Lessandro , Manicardi Alex , Madder Annemieke
Published: April 2021

G-Quadruplexes (G4s) are widely studied secondary DNA/RNA structures, naturally occurring when G-rich sequences are present. The strategic localization of G4s in genome areas of crucial importance, such as proto-oncogenes and telomeres, entails fundamental implications in terms of gene expression regulation and other important biological processes. Although thousands of small molecules capable to induce G4 stabilization have been reported over the past 20 years, approaches based on the hybridization of a synthetic probe, allowing sequence-specific G4-recognition and targeting are still rather limited. In this review, after introducing important general notions about G4s, we aim to list, explain and critically analyse in more detail the principal approaches available to target G4s by using oligonucleotides and synthetic analogues such as Locked Nucleic Acids (LNAs) and Peptide Nucleic Acids (PNAs), reporting on the most relevant examples described in literature to date.
Long-read whole-genome methylation patterning using enzymatic base conversion and nanopore sequencing
Authors: Sakamoto Yoshitaka , Zaha Suzuko , Nagasawa Satoi , Miyake Shuhei , Kojima Yasuyuki , Suzuki Ayako , Suzuki Yutaka , Seki Masahide
Published: April 2021

Long-read whole-genome sequencing analysis of DNA methylation would provide useful information on the chromosomal context of gene expression regulation. Here we describe the development of a method that improves the read length generated by using the bisulfite-sequencing-based approach. In this method, we combined recently developed enzymatic base conversion, where an unmethylated cytosine (C) should be converted to thymine (T), with nanopore sequencing. After methylation-sensitive base conversion, the sequencing library was constructed using long-range polymerase chain reaction. This type of analysis is possible using a minimum of 1 ng genomic DNA, and an N50 read length of 3.4–7.6 kb is achieved. To analyze the produced data, which contained a substantial number of base mismatches due to sequence conversion and an inaccurate base read of the nanopore sequencing, a new analytical pipeline was constructed. To demonstrate the performance of long-read methylation sequencing, breast cancer cell lines and clinical specimens were subjected to analysis, which revealed the chromosomal methylation context of key cancer-related genes, allele-specific methylated genes, and repetitive or deletion regions. This method should convert the intractable specimens for which the amount of available genomic DNA is limited to the tractable targets.
Total Petrosectomy for the Total Resection of Sphenopetroclival Meningioma: 2-Dimensional Operative Video
Authors: Aversa Antonio , Essayed Walid I B N , Al-Mefty Ossama
Published: April 2021

Sphenopetroclival meningioma is a most formidable meningioma. Many patients have few preoperative deficits and surgery has the potential of severe neurological complications. Surgical treatment is challenging due to brainstem compression, the involvement of multiple cranial nerves and cerebral vessels. Wide tumor exposure, multiple dissection axis, and short distance are paramount factors in the quest of achieving total removal of Simpson grade I, including the involved dura and bone. The posterior petrosal, transtentorial presigmoid approach offers a wide and shallow operative field.1–7
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When the patient has hearing loss, extending the resection of the temporal bone provides unmatchable exposure facilitating safer and more complete tumor removal. This article demonstrates the removal of a sphenopetroclival meningioma through total petrosectomy with closing of the external auditory canal and preservation of the facial nerve in the Fallopian canal. A total resection of the tumor was achieved with long-term preservation of cranial nerve function. The surgical steps of total petrosectomy are shown, including the skin flap, combined middle and posterior fossa craniotomy, skeletonization of the sigmoid transverse sinus, radical mastoidectomy, dissection of the Fallopian canal, and drilling of the labyrinth, cochlea, and petrous apex for superb exposure.
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We demonstrate the intra-arachnoidal microsurgical dissection utilized for the radical resection of petroclival meningioma. This surgery performed in 1995 is a testament to the time-tested technique. The patient consented to the procedure and image use.

Images at 1:33 and 3:57 © Ossama Al-Mefty, used with permission.
Ecological release and insular shifts in avian morphological traits in the Caribbean
Authors: Heathcote Alexandra , De Ruyck Christopher , Des Brisay Paulson , Grieef Paula , Koper Nicola
Published: April 2021

We compared support for 3 hypotheses that might explain observed morphological variation among islands of 4 species of Caribbean land birds: ecological release from competition and predation pressure, predation pressure from 1 novel predator species (small Indian mongoose, Herpestes auropunctatus), and climate. We measured wing chord, tarsus length, bill length, and mass of Bananaquits (Coereba flaveola), Black-faced Grassquits (Tiaris bicolor), Lesser Antillean Bullfinches (Loxigilla noctis), and Common Ground Doves (Columbina passerina) in Grenada, 2015–2017, and combined these measures with data from 23 other Caribbean islands collated from academic papers and researchers, for a total sample size of 6,518 individuals. We found the strongest support for the ecological release hypothesis, but each of our hypotheses received some support, suggesting that ecological release from competition, predation pressure from mongoose, and climate may all interact to influence morphological adaptations of birds to local conditions in the Caribbean.
The Relevance of Religion and Spirituality to Mental Health: A National Survey of Current Clients’ Views
Authors: Oxhandler Holly K , Pargament Kenneth I , Pearce Michelle J , Vieten Cassandra , Moffatt Kelsey M
Published: April 2021

Despite a growing interest in the relationship between religion and spirituality (RS) and mental health across helping professions, less is known about clients’ perceived relevance of these areas. This article describes the development and validation of the Relevance of Religion and Spirituality to Mental Health (RRSMH) scale, and responses to the first national survey of clients’ perceived relevance of RS to mental health. Specifically, a sample of 989 U.S. adults who saw a mental health care provider in the last month responded to an online survey that included 27 new items to measure clients’ perceptions of the relevance of RS to mental health, both positive and negative. A confirmatory factor analysis revealed that the sample’s data had an adequate fit to the final 12-item model, and the instrument’s overall reliability was very good (α = .96). Descriptive analyses indicated that clients view RS as both supportive and relevant to their mental health. The RRSMH scale may be used in mental health research and practice settings. Authors recommend that RS be assessed and included in treatment planning, where appropriate, and addressed in training for mental health professionals.
Low-dose computed tomography for axial spondyloarthritis: update on use and limitations
Authors: Lambert Robert G.W. , Hermann Kay Geert A. , Diekhoff Torsten
Published: April 2021

Purpose of review

Recent developments in low-dose computed tomography (ldCT) have greatly reduced radiation exposure levels. This article reviews what a ldCT is and its use and limitations for imaging axial spondyloarthritis.

Recent findings

Detection of structural damage in bone with CT is far superior to radiography and ldCT of the sacroiliac joints (SIJ) can now be done at radiation exposure levels equivalent to, or even less than, conventional radiography. ldCT should be considered a ‘first-choice’ test for arthritis imaging, and wherever available, SIJ ldCT may completely replace conventional radiography. Radiation exposure in the spine with ldCT is lower than conventional CT. However, it is unclear whether the additional information regarding structural damage changes in the spine provided by ldCT will alter patient management sufficiently often to merit switching from spinal radiography to ldCT in routine clinical practice. In addition, ldCT cannot assess osteitis disease activity for which MRI remains the best test.

ldCT of the sacroiliac joints (SIJ) can be done at radiation exposure levels equivalent to, or less than, radiography and ldCT may completely replace SIJ radiography. However, the role of spinal ldCT for spondyloarthritis is not clear and MRI is far superior for detecting disease activity.
The Use of a Novel Moldable Calcium Phosphate Putty (Montage) for Periarticular Fractures: Early Clinical Results
Authors: Atassi Omar H. , Busel Gennadiy , De La Fuente Guadalupe , Donohue David , Maxson Benjamin , Shah Anjan R. , Watson David T. , Infante Anthony , Downes Katheryne , Sanders Roy W. , Mir Hassan R.
Published: April 2021

Objective:

The objective of this study was to report on the early clinical results of a novel moldable calcium phosphate putty in managing metaphyseal voids associated with periarticular fractures.

Design:

This was a retrospective cohort study.

Setting:

Level I Academic Trauma Center.

Patients/Participants:

A total of 41 patients with periarticular fractures treated from June 2017 to June 2018 were included in the study.

Intervention:

Open reduction internal fixation.

Main Outcome Measurement:

Articular subsidence, bone void filler incorporation and resorption, calcium phosphate extravasation into soft tissue and joint, nonunion, infection.

Results:

Fracture distribution was as follows: 23 plateau, 6 pilon, 5 acetabulum, 4 calcaneus, 1 midfoot, 1 olecranon, 1 distal radius. Twenty-six patients had >6-month follow-up at the time of publication. All fractures have united. There were no instances in which the Montage extravasated into the soft tissue or joint. In all, 23/26 (88%) patients went on to union without articular subsidence. Overall, 25/26 (96%) showed radiographic evidence of incorporation and partial resorption. There were 2 unplanned surgeries (8%). One patient had an open pilon fracture that underwent debridement and implant removal at 4 months for deep infection; 1 patient with a tibial plateau fracture underwent debridement with implant retention at 4 weeks for deep infection. Both went on to clinical and radiographic union.

Conclusions:

Montage shows excellent efficacy in preventing articular subsidence when used as a metaphyseal void filler with fixation of periarticular fractures. There is strong radiographic evidence of incorporation and partial resorption at early clinical follow-up. The handling characteristics during its application showed no soft tissue or intra-articular extravasation. Early clinical results are promising, and further study is warranted.

Level of Evidence:

Level IV.