bluuebunny/crossref_metadata_2025 huggingface dataset:
One Way or Another: Cortical Language Areas Flexibly Adapt Processing Strategies to Perceptual And Contextual Properties of Speech
Authors: Klimovich-Gray Anastasia , Barrena Ander , Agirre Eneko , Molinaro Nicola
Published: March 2021

Cortical circuits rely on the temporal regularities of speech to optimize signal parsing for sound-to-meaning mapping. Bottom-up speech analysis is accelerated by top–down predictions about upcoming words. In everyday communications, however, listeners are regularly presented with challenging input—fluctuations of speech rate or semantic content. In this study, we asked how reducing speech temporal regularity affects its processing—parsing, phonological analysis, and ability to generate context-based predictions. To ensure that spoken sentences were natural and approximated semantic constraints of spontaneous speech we built a neural network to select stimuli from large corpora. We analyzed brain activity recorded with magnetoencephalography during sentence listening using evoked responses, speech-to-brain synchronization and representational similarity analysis. For normal speech theta band (6.5–8 Hz) speech-to-brain synchronization was increased and the left fronto-temporal areas generated stronger contextual predictions. The reverse was true for temporally irregular speech—weaker theta synchronization and reduced top–down effects. Interestingly, delta-band (0.5 Hz) speech tracking was greater when contextual/semantic predictions were lower or if speech was temporally jittered. We conclude that speech temporal regularity is relevant for (theta) syllabic tracking and robust semantic predictions while the joint support of temporal and contextual predictability reduces word and phrase-level cortical tracking (delta).
School Mental Health Providers’ Perspectives on the Impact of COVID-19 on Racial Inequities and School Disengagement
Authors: Jones Tiffany M , Williford Anne , Spencer Michael S , Riggs Nathaniel R , Toll Rebecca , George Melissa , Becker Kaylee , Bruick Samantha
Published: March 2021

School disengagement is a critical factor that will likely exacerbate long-standing racial inequities in educational outcomes during the aftermath of the coronavirus disease (COVID-19) pandemic. Due to their training and contact with at-risk students, school social workers and other school-based mental health professionals (SMHP) are in an ideal position to understand the impact of COVID-19 and virtual learning on K–12 students. To that end, this study reports on findings from a survey of SMHP about the differential impact that the COVID-19 outbreak is having on students and their families. The findings suggest that COVID-19 has had a tremendous impact on families overall, especially among populations who were experiencing hardships before the current outbreak. In addition, several barriers were noted for student learning, with many students—particularly students of color—completely disengaging from school during spring 2020. However, SMHP reported several important insights on how to support students and their families—some requiring immediate action on the part of school districts and others requiring greater community-level investment into the economic, social, emotional, and overall health of families. Findings are discussed in light of addressing disengagement and educational inequities for students of color.
Guided by images—Chilean novice teachers’ visions of themselves
Authors: Glas Katharina , Dittmar Patricia , Allendes Paz
Published: March 2021

Mental imagery of ‘future selves’ is considered a powerful means for motivating learners, and also teachers, whose own motivation is an important basis for the creation of engaging teaching–learning environments. This multiple case study accompanied Chilean novice teachers of English over 18 months and explores the use of visualizations of teacher selves as a reflection tool in early career development. What images of themselves and their classroom environments do novice teachers create when prompted to visualize themselves as ‘motivating teachers’? What role do these visualizations play in supporting novice teachers in implementing methodological innovations? And do novice teachers value the use of visualizations? Two contrasting cases demonstrate variability in the evolution of visions, and illustrate how these can fulfil different roles in assisting teachers during their induction phase.
Clinical and demographic correlates of accelerometer-measured physical activity in participants enrolled in the OPTIMISE HFpEF study
Authors: Lin Helen , Hartley Peter , Forsyth Faye , Pilling Mark , Hobbs F D Richard , Taylor Clare J , Schiff Rebekah , Deaton Christi
Published: March 2021

Aims

This study aimed to measure physical activity (PA) in participants with suspected heart failure with preserved ejection fraction (HFpEF) and assess associations between PA and participant characteristics.

Methods and results

Adults with presumed HFpEF were recruited and received diagnostic evaluation and clinical assessment. Physical activity was objectively measured using accelerometers over 7 days. To examine predictors of PA, a best subset analysis was used, with the optimal model defined as that with the lowest Bayesian information criterion. One hundred and twenty-four participants with presumed HFpEF who had valid accelerometer data were included in this study. Seventy-six were confirmed by a cardiologist as meeting the European Society of Cardiology diagnosis criteria for HFpEF. The median age of all participants was 80.1 years, and 47.4% were female. Patients spent most of each 24-h period at low-intensity PA and few or no durations at high-intensity PA, with lower activity for those with HFpEF. Gait speed was the best univariate correlate of activity levels (adjusted R2 0.29). The optimal model using best subsets regression included six variables and improved adjusted R2 to 0.47. In the model, lower levels of PA were associated with slower gait speed, lower levels of anxiety, higher levels of depression, past smoking history, a confirmed HFpEF diagnosis, and higher body mass index.

Conclusion

Participants demonstrated very low PA levels. The study has identified important patient characteristics associated with PA, which may help to identify those most in need of interventions. Notably, participants with confirmed HFpEF were more inactive than participants with other heart failure phenotypes.
Marine sediments harbor diverse archaea and bacteria with the potential for anaerobic hydrocarbon degradation via fumarate addition
Authors: Zhang Chuwen , Meckenstock Rainer U , Weng Shengze , Wei Guangshan , Hubert Casey R J , Wang Jiang-Hai , Dong Xiyang
Published: March 2021

Marine sediments can contain large amounts of alkanes and methylated aromatic hydrocarbons that are introduced by natural processes or anthropogenic activities. These compounds can be biodegraded by anaerobic microorganisms via enzymatic addition of fumarate. However, the identity and ecological roles of a significant fraction of hydrocarbon degraders containing fumarate-adding enzymes (FAE) in various marine sediments remains unknown. By combining phylogenetic reconstructions, protein homolog modelling, and functional profiling of publicly available metagenomes and genomes, 61 draft bacterial and archaeal genomes encoding anaerobic hydrocarbon degradation via fumarate addition were obtained. Besides Desulfobacterota (previously known as Deltaproteobacteria) that are well-known to catalyze these reactions, Chloroflexi are dominant FAE-encoding bacteria in hydrocarbon-impacted sediments, potentially coupling sulfate reduction or fermentation to anaerobic hydrocarbon degradation. Among Archaea, besides Archaeoglobi previously shown to have this capability, genomes of Heimdallarchaeota, Lokiarchaeota, Thorarchaeota and Thermoplasmata also suggest fermentative hydrocarbon degradation using archaea-type FAE. These bacterial and archaeal hydrocarbon degraders occur in a wide range of marine sediments, including high abundances of FAE-encoding Asgard archaea associated with natural seeps and subseafloor ecosystems. Our results expand the knowledge of diverse archaeal and bacterial lineages engaged in anaerobic degradation of alkanes and methylated aromatic hydrocarbons.
Selection and characterization of twoBacillus thuringiensisstrains showing nematicidal activity againstCaenorhabditis elegansandMeloidogyne incognita
Authors: Verduzco-Rosas Luis A , García-Suárez Rosalina , López-Tlacomulco José J , Ibarra Jorge E
Published: March 2021

Bacillus thuringiensis has been widely used as a biological control agent against insect pests. Additionally, nematicidal strains have been under investigation. In this report, 310 native strains of B. thuringiensis against Caenorhabditis elegans were tested. Only the LBIT-596 and LBIT-107 strains showed significant mortality. LC50s of spore-crystal complexes were estimated at 37.18 and 31.89 μg/mL for LBIT-596 and LBIT-107 strains, respectively, while LC50s of partially purified crystals was estimated at 23.76 and 20.25 μg/mL for LBIT-596 and LBIT-107, respectively. The flagellin gene sequence and plasmid patterns indicated that LBIT-596 and LBIT-107 are not related to each other. Sequences from internal regions of a cry5B and a cyt1A genes were found in the LBIT-596 strain, while a cry21A, a cry14A and a cyt1A genes were found in the LBIT-107 strain. Genome sequence of the LBIT-107 strain showed new cry genes, along with other virulence factors, hence, total nematicidal activity of the LBIT-107 strain may be the result of a multifactorial effect. The highlight of this contribution is that translocation of spore-crystal suspensions of LBIT-107 into tomato plants inoculated at their rhizosphere decreased up to 90% the number of galls of Meloidogyne incognita, perhaps the most important nematode pest in the world.
X chromosome-dependent disruption of placental regulatory networks in hybrid dwarf hamsters
Authors: Brekke Thomas D , Moore Emily C , Campbell-Staton Shane C , Callahan Colin M , Cheviron Zachary A , Good Jeffrey M
Published: March 2021

Embryonic development in mammals is highly sensitive to changes in gene expression within the placenta. The placenta is also highly enriched for genes showing parent-of-origin or imprinted expression, which is predicted to evolve rapidly in response to parental conflict. However, little is known about the evolution of placental gene expression, or if divergence of placental gene expression plays an important role in mammalian speciation. We used crosses between two species of dwarf hamsters (Phodopus sungorus and Phodopus campbelli) to examine the genetic and regulatory underpinnings of severe placental overgrowth in their hybrids. Using quantitative genetic mapping and mitochondrial substitution lines, we show that overgrowth of hybrid placentas was primarily caused by genetic differences on the maternally inherited P. sungorus X chromosome. Mitochondrial interactions did not contribute to abnormal hybrid placental development, and there was only weak correspondence between placental disruption and embryonic growth. Genome-wide analyses of placental transcriptomes from the parental species and first- and second-generation hybrids revealed a central group of co-expressed X-linked and autosomal genes that were highly enriched for maternally biased expression. Expression of this gene network was strongly correlated with placental size and showed widespread misexpression dependent on epistatic interactions with X-linked hybrid incompatibilities. Collectively, our results indicate that the X chromosome is likely to play a prominent role in the evolution of placental gene expression and the accumulation of hybrid developmental barriers between mammalian species.
Genome sequence and genetic diversity analysis of an under-domesticated orphan crop, white fonio (Digitaria exilis)
Authors: Wang Xuewen , Chen Shiyu , Ma Xiao , Yssel Anna E J , Chaluvadi Srinivasa R , Johnson Matthew S , Gangashetty Prakash , Hamidou Falalou , Sanogo Moussa D , Zwaenepoel Arthur , Wallace Jason , de Peer Yves , Bennetzen Jeffrey L , Van Deynze Allen
Published: March 2021

Background

Digitaria exilis, white fonio, is a minor but vital crop of West Africa that is valued for its resilience in hot, dry, and low-fertility environments and for the exceptional quality of its grain for human nutrition. Its success is hindered, however, by a low degree of plant breeding and improvement.

Findings

We sequenced the fonio genome with long-read SMRT-cell technology, yielding a ∼761 Mb assembly in 3,329 contigs (N50, 1.73 Mb; L50, 126). The assembly approaches a high level of completion, with a BUSCO score of >99%. The fonio genome was found to be a tetraploid, with most of the genome retained as homoeologous duplications that differ overall by ∼4.3%, neglecting indels. The 2 genomes within fonio were found to have begun their independent divergence ∼3.1 million years ago. The repeat content (>49%) is fairly standard for a grass genome of this size, but the ratio of Gypsy to Copia long terminal repeat retrotransposons (∼6.7) was found to be exceptionally high. Several genes related to future improvement of the crop were identified including shattering, plant height, and grain size. Analysis of fonio population genetics, primarily in Mali, indicated that the crop has extensive genetic diversity that is largely partitioned across a north-south gradient coinciding with the Sahel and Sudan grassland domains.

Conclusions

We provide a high-quality assembly, annotation, and diversity analysis for a vital African crop. The availability of this information should empower future research into further domestication and improvement of fonio.
Bulk modulus for fluid-saturated rocks at intermediate frequencies: modification of squirt flow model proposed by Gurevich et al.
Authors: Zhao Liming , Chen Tongjun , Tang Genyang
Published: March 2021

Squirt flow is an essential cause of wave dispersion and attenuation in saturated rocks. The squirt flow model, proposed by Gurevich et al., has been widely applied to explain the wave dispersion and associated attenuation for saturated rocks at sonic and seismic frequency bands. In this model, the saturated bulk modulus is obtained by taking the partially relaxed frame bulk modulus as the dry frame modulus into Gassmann's formula with the mineral bulk modulus as the matrix bulk modulus. However, because of the weakening effect of soft pores on rock matrix bulk modulus, the model cannot accurately predict the saturated bulk modulus when the soft-pore fraction (the ratio of the soft porosity to total porosity) becomes large. We modified this model following Gurevich et al. by setting a different boundary condition. The modified squirt flow model can obtain correct saturated bulk modulus for large soft-pore fractions in the full range of frequencies, showing excellent consistency with the predictions of Gassmann, Mavko & Jizba (modified) at both low- and high-frequency limits, respectively. Modelling results show that the saturated bulk moduli and their dispersions calculated by the original and modified models exhibit little difference when the soft-pore fraction is small. Under this condition, the original model is as effective and accurate as the modified one. When the soft-pore fraction becomes larger, the differences in the bulk moduli and their dispersions become substantial, suggesting the original model is not applicable any longer. Furthermore, the differences calculated for the intermediate frequency range is even more obvious than other ranges, suggesting that the modified model should be used to calculate the bulk modulus and the dispersion in this frequency range. In summary, the modified squirt flow model can extend the original model's applicable range in terms of soft-pore fraction and has a potential application in rocks having a relatively large amount of soft-pore fraction such as basalts.
Imaging of a magma system beneath the Merapi Volcano complex, Indonesia, using ambient seismic noise tomography
Authors: Yudistira T , Metaxian J-P , Putriastuti M , Widiyantoro S , Rawlinson N , Beauducel F , Zulfakriza Z , Nugraha A D , Laurin A , Fahmi A A , Budi-Santoso A
Published: March 2021

Mt Merapi, which lies just north of the city of Yogyakarta in Java, Indonesia, is one of the most active and dangerous volcanoes in the world. Thanks to its subduction zone setting, Mt Merapi is a stratovolcano, and rises to an elevation of 2968 m above sea level. It stands at the intersection of two volcanic lineaments, Ungaran–Telomoyo–Merbabu–Merapi (UTMM) and Lawu–Merapi–Sumbing–Sindoro–Slamet, which are oriented north–south and west–east, respectively. Although it has been the subject of many geophysical studies, Mt Merapi's underlying magmatic plumbing system is still not well understood. Here, we present the results of an ambient seismic noise tomography study, which comprise of a series of Rayleigh wave group velocity maps and a 3-D shear wave velocity model of the Merapi–Merbabu complex. A total of 10 months of continuous data (October 2013–July 2014) recorded by a network of 46 broad-band seismometers were used. We computed and stacked daily cross-correlations from every pair of simultaneously recording stations to obtain the corresponding inter-station empirical Green's functions. Surface wave dispersion information was extracted from the cross-correlations using the multiple filtering technique, which provided us with an estimate of Rayleigh wave group velocity as a function of period. The group velocity maps for periods 3–12 s were then inverted to obtain shear wave velocity structure using the neighbourhood algorithm. From these results, we observe a dominant high velocity anomaly underlying Mt Merapi and Mt Merbabu with a strike of 152°N, which we suggest is evidence of old lava dating from the UTMM double-chain volcanic arc which formed Merbabu and Old Merapi. We also identify a low velocity anomaly on the southwest flank of Merapi which we interpret to be an active magmatic intrusion.
Mevolectin specificity toward high-mannose structures with terminal αMan(1,2)αMan residues and its implication to inhibition of the entry ofMycobacterium tuberculosisinto macrophages
Authors: Sivaji Nukathoti , Harish Nikitha , Singh Samsher , Singh Amit , Vijayan Mamannamana , Surolia Avadhesha
Published: March 2021

Mannose-binding lectins can specifically recognize and bind complex glycan structures on pathogens and have potential as antiviral and antibacterial agents. We previously reported the structure of a lectin from an archaeal species, Mevo lectin, which has specificity toward terminal α1,2 linked manno-oligosaccharides. Mycobacterium tuberculosis expresses mannosylated structures including lipoarabinomannan (ManLAM) on its surface and exploits C-type lectins to gain entry into the host cells. ManLAM structure has mannose capping with terminal αMan(1,2)αMan residues and is important for recognition by innate immune cells. Here, we aim to address the specificity of Mevo lectin toward high-mannose type glycans with terminal αMan(1,2)αMan residues and its effect on M. tuberculosis internalization by macrophages. Isothermal titration calorimetry studies demonstrated that Mevo lectin shows preferential binding toward manno-oligosaccharides with terminal αMan(1,2)αMan structures and showed a strong affinity for ManLAM, whereas it binds weakly to Mycobacterium smegmatis lipoarabinomannan, which displays relatively fewer and shorter mannosyl caps. Crystal structure of Mevo lectin complexed with a Man7D1 revealed the multivalent cross-linking interaction, which explains avidity-based high-affinity for these ligands when compared to previously studied manno-oligosaccharides lacking the specific termini. Functional studies suggest that M. tuberculosis internalization by the macrophage was impaired by binding of Mevo lectin to ManLAM present on the surface of M. tuberculosis. Selectivity shown by Mevo lectin toward glycans with terminal αMan(1,2)αMan structures, and its ability to compromise the internalization of M. tuberculosis  in vitro, underscore the potential utility of Mevo lectin as a research tool to study host-pathogen interactions.
Voluntary fishing restrictions alone do not promote growth of bryozoan-dominated biogenic habitat on the Otago shelf, southeastern New Zealand
Authors: Mello H Lee , Smith Abigail M , Wood Anna C L
Published: March 2021

On the continental shelf, New Zealand bryozoans dominate ecologically-important three-dimensional benthic habitat providing structural complexity which hosts a wide variety of fauna, including economically valuable species (e.g. oysters and blue cod). The association between these species and bryozoan-dominated biogenic habitat commonly results in trawling damage to the benthos; eliminating pressure from destructive fishing practices could support bryozoan regrowth. In 2002, a voluntary fishing restriction was designated over part of one such bryozoan-dominated biogenic habitat, but the efficacy of this ban has not been assessed. Statutory marine protected areas have been proposed in the same area; they aim to achieve bryozoan protection and recovery. A comparison of the bryozoan fauna using benthic images from 2003 and 2019 from the Otago shelf, South Island, New Zealand/Te Waipounamu, Aotearoa shows that a 17-year voluntary fishing ban has been ineffective at increasing the cover and richness of bryozoan-dominated biogenic habitat on the Otago shelf. This study provides a baseline for future monitoring and develops useful metrics for recovery, while calling for further research on the biology and ecology of habitat-forming bryozoans.
Quantifying the contribution of modifiable risk factors to socio-economic inequities in cancer morbidity and mortality: a nationally representative population-based cohort study
Authors: Nejatinamini Sara , Godley Jenny , Minaker Leia M , Sajobi Tolulope T , McCormack Gavin R , Cooke Martin J , Nykiforuk Candace I J , Koning Lawrence de , Olstad Dana Lee
Published: March 2021

Background

Compared with those with a higher socio-economic position (SEP), individuals with a lower SEP have higher cancer morbidity and mortality. However, the contribution of modifiable risk factors to these inequities is not known. This study aimed to quantify the mediating effects of modifiable risk factors to associations between SEP and cancer morbidity and mortality.

Methods

This study used a prospective observational cohort design. We combined eight cycles of the Canadian Community Health Survey (2000/2001–2011) as baseline data to identify a cohort of adults (≥35 years) without cancer at the time of survey administration (n = 309 800). The cohort was linked to the Discharge Abstract Database and the Canadian Mortality Database for cancer morbidity and mortality ascertainment. Individuals were followed from the date they completed the Canadian Community Health Survey until 31 March 2013. Dates of individual first hospitalizations for cancer and deaths due to cancer were captured during this time period. SEP was operationalized using a latent variable combining measures of education and household income. Self-reported modifiable risk factors, including smoking, excess alcohol consumption, low fruit-and-vegetable intake, physical inactivity and obesity, were considered as potential mediators. Generalized structural equation modelling was used to estimate the mediating effects of modifiable risk factors in associations between low SEP and cancer morbidity and mortality in the total population and stratified by sex.

Results

Modifiable risk factors together explained 45.6% of associations between low SEP and overall cancer morbidity and mortality. Smoking was the most important mediator in the total population and for males, accounting for 15.5% and 40.2% of the total effect, respectively. For females, obesity was the most important mediator.

Conclusions

Modifiable risk factors are important mediators of socio-economic inequities in cancer morbidity and mortality. Nevertheless, more than half of the variance in these associations remained unexplained. Midstream interventions that target modifiable risk factors may help to alleviate inequities in cancer risk in the short term. However, ultimately, upstream interventions that target structural determinants of health are needed to reduce overall socio-economic inequities in cancer morbidity and mortality.
IL-6: from arthritis to CAR-T-cell therapy and COVID-19
Authors: Kishimoto Tadamitsu
Published: March 2021

Blockade of IL-6 function by an anti-IL-6 receptor (IL-6R) antibody (tocilizumab, trade name Actemra) has been shown to be effective for the treatment of chronic autoimmune inflammatory diseases including rheumatoid arthritis. Interestingly, treatment with tocilizumab has also been found to alleviate the cytokine storm induced by chimeric antigen receptor (CAR)-T-cell therapy. Patients with serious cases of coronavirus disease 2019 (COVID-19) exhibit cytokine release syndrome (CRS), which suggested that tocilizumab might be an effective therapeutic for serious cases of COVID-19. In the first part of this short review, the therapeutic effect of tocilizumab for the disease induced by IL-6 overproduction is described. CRS induced by CAR-T-cell therapy and COVID-19 is then discussed.
Systematics of the rodent genusNeacomysThomas (Cricetidae: Sigmodontinae): two new species and a discussion on carotid patterns
Authors: Caccavo Aldo , Weksler Marcelo
Published: March 2021

The taxonomy of the oryzomyine genus Neacomys currently is in a state of flux: systematic studies in the last 20 years increased its diversity from four to 16 species, with an additional several undescribed phylogenetic lineages. Despite this progress, morphological variation and species limits remain poorly known for several species groups and complexes within the genus, such as N. tenuipes, N. musseri, and N. dubosti. Here we analyze the variation of morphological characters and morphometric patterns of two new candidate species of Neacomys for northern Venezuela and Pará state, Brazil, that are characterized by the presence of derived carotid circulation, a rare character state for the genus. Analyzed material included holotypes, type series, and/or topotypes of almost all described species of Neacomys, including type series of N. musseri, the holotype of N. tenuipes, and sequenced specimens of N. xingu. Qualitative comparison showed that 25 characters are informative for the distinction of the two new forms, and morphometric analyses corroborated the morphological separation of the new species. Results also point that N. tenuipes might represent a species complex. The new forms are sympatric with other species, including N. tenuipes and N. xingu, and can be identified by a suite of morphological characters, including the presence of a derived carotid pattern and, for the Pará form, by a unique morphology of the first upper molar. We review the occurrence of carotid circulation patterns within Sigmodontinae and discuss its use for the systematics of the subfamily. Further studies involving the new Neacomys species will contribute to understanding the biogeographic patterns and evolutionary trends within this distinct and diverse genus.
The Logicality of Language: Contextualism versus Semantic Minimalism
Authors: Del Pinal Guillermo
Published: March 2021

The logicality of language is the hypothesis that the language system has access to a ‘natural’ logic that can identify and filter out as unacceptable expressions that have trivial meanings—that is, that are true/false in all possible worlds or situations in which they are defined. This hypothesis helps explain otherwise puzzling patterns concerning the distribution of various functional terms and phrases. Despite its promise, logicality vastly over-generates unacceptability assignments. Most solutions to this problem rest on specific stipulations about the properties of logical form—roughly, the level of linguistic representation which feeds into the interpretation procedures—and have substantial implications for traditional philosophical disputes about the nature of language. Specifically, contextualism and semantic minimalism, construed as competing hypotheses about the nature and degree of context-sensitivity at the level of logical form, suggest different approaches to the over-generation problem. In this paper, I explore the implications of pairing logicality with various forms of contextualism and semantic minimalism. I argue that to adequately solve the over-generation problem, logicality should be implemented in a constrained contextualist framework.
Structured variational inference for simulating populations of radio galaxies
Authors: Bastien David J , Scaife Anna M M , Tang Hongming , Bowles Micah , Porter Fiona
Published: March 2021

We present a model for generating postage stamp images of synthetic Fanaroff–Riley Class I and Class II radio galaxies suitable for use in simulations of future radio surveys such as those being developed for the Square Kilometre Array. This model uses a fully connected neural network to implement structured variational inference through a variational autoencoder and decoder architecture. In order to optimize the dimensionality of the latent space for the autoencoder, we introduce the radio morphology inception score (RAMIS), a quantitative method for assessing the quality of generated images, and discuss in detail how data pre-processing choices can affect the value of this measure. We examine the 2D latent space of the VAEs and discuss how this can be used to control the generation of synthetic populations, whilst also cautioning how it may lead to biases when used for data augmentation.
Fomalhaut b could be massive and sculpting the narrow, eccentric debris disc, if in mean-motion resonance with it
Authors: Pearce Tim D , Beust Hervé , Faramaz Virginie , Booth Mark , Krivov Alexander V , Löhne Torsten , Poblete Pedro P
Published: March 2021

The star Fomalhaut hosts a narrow, eccentric debris disc, plus a highly eccentric companion Fomalhaut b. It is often argued that Fomalhaut b cannot have significant mass, otherwise it would quickly perturb the disc. We show that material in internal mean-motion resonances with a massive, coplanar Fomalhaut b would actually be long-term stable, and occupy orbits similar to the observed debris. Furthermore, millimetre dust released in collisions between resonant bodies could reproduce the width, shape, and orientation of the observed disc. We first re-examine the possible orbits of Fomalhaut b, assuming that it moves under gravity alone. If Fomalhaut b orbits close to the disc mid-plane then its orbit crosses the disc, and the two are apsidally aligned. This alignment may hint at an ongoing dynamical interaction. Using the observationally allowed orbits, we then model the interaction between a massive Fomalhaut b and debris. While most debris is unstable in such an extreme configuration, we identify several resonant populations that remain stable for the stellar lifetime, despite crossing the orbit of Fomalhaut b. This debris occupies low-eccentricity orbits similar to the observed debris ring. These resonant bodies would have a clumpy distribution, but dust released in collisions between them would form a narrow, relatively smooth ring similar to observations. We show that if Fomalhaut b has a mass between those of Earth and Jupiter then, far from removing the observed debris, it could actually be sculpting it through resonant interactions.
The most massive white dwarfs in the solar neighbourhood
Authors: Kilic Mukremin , Bergeron P , Blouin Simon , Bédard A
Published: March 2021

We present an analysis of the most massive white dwarf candidates in the Montreal White Dwarf Database 100 pc sample. We identify 25 objects that would be more massive than $1.3\, {\rm M}_{\odot }$ if they had pure H atmospheres and CO cores, including two outliers with unusually high photometric mass estimates near the Chandrasekhar limit. We provide follow-up spectroscopy of these two white dwarfs and show that they are indeed significantly below this limit. We expand our model calculations for CO core white dwarfs up to M = 1.334 M⊙, which corresponds to the high-density limit of our equation-of-state tables, ρ = 109 g cm−3. We find many objects close to this maximum mass of our CO core models. A significant fraction of ultramassive white dwarfs are predicted to form through binary mergers. Merger populations can reveal themselves through their kinematics, magnetism, or rapid rotation rates. We identify four outliers in transverse velocity, four likely magnetic white dwarfs (one of which is also an outlier in transverse velocity), and one with rapid rotation, indicating that at least 8 of the 25 ultramassive white dwarfs in our sample are likely merger products.
Association Between Vancomycin Area Under the Curve and Nephrotoxicity: a single center, retrospective cohort study in a veteran population
Authors: Poston-Blahnik Anna , Moenster Ryan
Published: March 2021

Background

It is unclear which vancomycin area under the curve (AUC) values are most associated with risk for acute kidney injury (AKI).

Methods

This retrospective cohort study was undertaken to determine if vancomycin AUC >550 is associated with a higher rate of AKI than an AUC <550. Patients treated with vancomycin for at least 4 days at the VA St. Louis Health Care System from 1/1/2016 to 9/31/2018 were included. The primary outcome was AKI (defined as an increase in serum creatinine by 0.3 mg/dL or 50% from baseline). Secondary outcomes included length of stay, readmission in 30 days, and mortality in 30 days. A bivariate analysis was used to determine other potential factors affecting AKI rate, with significant variables (P < .2) to be included in the multivariate logistic regression analysis to determine independent risk for AKI.

Results

Two hundred patients were included in the analysis; 100 patients with an AUC ≥550 and 100 with an AUC <550. Only mean vancomycin dose (1722.50 mg vs 2361.25 mg; P < .05), mean AUC (465.88 vs 696.45; P < .05), and peak SCr (1.22 mg/dL vs 1.48 mg/dL; P = .015) were significantly different between groups (AUC <550 vs AUC ≥550, respectively). AKI occurred in 42% (42/100) of patients with AUC ≥550 compared with 2% (2/100) of patients with AUC <550 (P < .05). Secondary outcomes were not different between the groups. In the bivariate analysis, age ≥70, CrCl <50 mL/min, and AUC ≥550 (odds ratio, 49.5; 95% CI, 10.1–242.3; P < .05) were found to be independently associated with risk for developing AKI.

Conclusions

Patients with a vancomycin AUC ≥550 were found to have a significantly higher rate of AKI compared with those with an AUC <550.
Clustering of SARS-CoV-2 Infections in Households of Patients Diagnosed in the Outpatient Setting in Baltimore, Maryland
Authors: Demko Zoe O , Antar Annukka A R , Blair Paul W , Lambrou Anastasia S , Yu Tong , Brown Diane , Walch Samantha N , Armstrong Derek T , Mostafa Heba H , Keruly Jeanne C , Thomas David L , Manabe Yukari C , Mehta Shruti H ,   Ambulatory COVID Study Team, Reuland Carolyn , Azamfirei Razvan , Hardick Justin P , Church Taylor , Sewell Thelio T , Keller Sara , Sauer Lauren , Tornheim Jeffrey , Townsend Jennifer , Bachu Vismaya , Barnaba Brittany , Charles Curtisha , Dai Weiwei , Payton Christine , Fuchs Joelle , Holden Jeffrey , Jang Minyoung , Johnstone J R , Kruczynski Kate , Kusemiju Oyinkansola , Li Lucy , Tuchler Amanda , Montana Manuela Plazas , Prizzi Michelle , Ursin Rebecca
Published: March 2021

In an outpatient cohort in Maryland, clustering of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positivity within households was high, with 76% of 74 households reporting at least 1 other symptomatic person and 66% reporting another person who tested SARS-CoV-2 positive. SARS-CoV-2 positivity among household members was associated with larger household size and bedroom sharing.
Evaluation of a Cryptococcal Antigen Lateral Flow Assay and Cryptococcal Antigen Positivity at a Large Public Hospital in Atlanta, Georgia
Authors: Harrington Kristin R V , Wang Yun F , Rebolledo Paulina A , Liu Zhiyong , Yang Qianting , Kempker Russell R
Published: March 2021

Background

Cryptococcus neoformans is a major cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected persons worldwide, and there are scarce recent data on cryptococcal antigen (CrAg) positivity in the United States We sought to determine the frequency of cryptococcal disease and compare the performance of a CrAg lateral flow assay (LFA) versus latex agglutination (LA) test.

Methods

All patients from Grady Health System in Atlanta who had a serum or cerebrospinal fluid (CSF) sample sent for CrAg testing as part of clinical care from November 2017 to July 2018 were included. Percentage positivity and test agreement were calculated.

Results

Among 467 patients, 557 diagnostic tests were performed; 413 on serum and 144 on CSF. The mean age was 44 years, and most were male (69%) and had HIV (79%). Twenty-four (6.4%, 95% confidence interval [CI] = 4.1–9.4) patients were serum CrAg positive, and 8 (5.8%, 95% CI = 2.6–11.2) individuals tested positive for CSF CrAg. Although overall agreement between the LA and LFA was substantial to high for CSF (κ = 0.71, 95% CI = 0.51–0.91) and serum (κ = 0.93, 95% CI = 0.86–1.00), respectively, there were important discrepancies. Five patients had false-positive CSF LA tests that affected clinical care, and 4 patients had discordant serum tests.

Conclusions

We found a moderately high proportion of cryptococcal disease and important discrepancies between the LA test and LFA. Clinical implications of these findings include accurate detection of serum CrAg and averting unnecessary treatment of meningitis with costly medications associated with high rates of adverse events.
‘When I asked for help and support it was not there’: current NHS employment practice and its impact on people with systemic lupus erythematosus
Authors: Booth Sara , Price Elizabeth , Walker Elizabeth
Published: March 2021

Objectives

The aim was to investigate whether National Health Service (NHS) employees with SLE, for whom work disability and early retirement are high, are supported effectively in at work.

Methods

An online survey of 393 people with lupus was completed through the LUPUS UK website, investigating participants’ experiences in maintaining employment. Quantitative and qualitative data were collected. Disease fluctuation, invisibility and fatigue were identified as having substantial negative impacts on employment. This study examined data from a large subgroup (n = 72, 18.74%) of current/previous NHS employees. Descriptive statistics and thematic analysis were used to explore and characterize the demography and experiences of participants.

Results

The NHS subgroup (n = 72) represented 18.74% of the whole cohort; 100% were female and of working age (18–64 years). Fifty-one were currently (70.8%) and 21 previously (29.2%) NHS employees. Forty-nine (60%) were clinicians. Twenty-one (29.16%) of this working-age subgroup had left any employment. Negative effects of SLE on employment were universal (including an impact on career choices, work disability, enforced part-time working, lower income and early retirement). NHS support for participants to maintain employment was inconsistent, with more negative experiences than positive. The impact of SLE on employment seemed to be poorly understood.

Conclusion

A punitive approach to NHS employees with SLE was more common than a proactive, flexible, problem-solving one despite inclusive rhetoric, resulting in the loss of skills and experience to the service. Characterizing conditions such as SLE and long coronavirus disease 2019 as fluctuating, invisible conditions with constitutional symptoms highlights features with negative employment impact, potentially facilitating much-needed change in NHS organizations, with greater use of occupational health, vocational rehabilitation, redeployment and retraining opportunities, highlighting the need for evidence-based employment interventions and improved management of fatigue.
Biomimetic cell-adhesive ligand-functionalized peptide composite hydrogels maintain stemness of human amniotic mesenchymal stem cells
Authors: Zhang Ling , Xiong Na , Liu Yanfei , Gan Lili
Published: March 2021

In vivo, stem cells reside in a three-dimensional (3D) extracellular microenvironment in which complicated biophysical and biochemical factors regulate their behaviors. Biomimicking of the stem cell−matrix interactions is an ideal approach for controlling the stem cell fate. This study investigates the effects of the incorporation of cell-adhesive ligands in 3D self-assembling peptide hydrogels to modulate stem cell survival, proliferation, maintenance of stemness, and osteogenic differentiation. The results show that the composite hydrogels were non-cytotoxic and effective for maintaining human amniotic mesenchymal stem cell (hAMSC) survival, proliferation and phenotypic characterization. The expression levels of pluripotent markers were also upregulated in the composite hydrogels. Under inductive media conditions, mineral deposition and mRNA expression levels of osteogenic genes of hAMSCs were enhanced. The increasing expression of integrin α- and β-subunits for hAMSCs indicates that the ligand−integrin interactions may modulate the cell fate for hAMSCs in composite hydrogels.
Inequalities in Psychiatric Service Use and Mortality by Migrant Status Following a First Diagnosis of Psychotic Disorder: A Swedish Cohort Study of 1.3M People
Authors: Katsampa Dafni , Akther Syeda F , Hollander Anna-Clara , Dal Henrik , Dalman Christina , Kirkbride James B
Published: March 2021

It is unclear whether inequalities in mental healthcare and mortality following the onset of psychosis exist by migrant status and region-of-origin. We investigated whether (1) mortality (including by major causes of death); (2) first admission type (inpatient or outpatient); (3) in-patient length of stay (LOS) at first diagnosis for psychotic disorder presentation, and; (4) time-to-readmission for psychotic disorder differed for refugees, non-refugee migrants, and by region-of-origin. We established a cohort of 1 335 192 people born 1984–1997 and living in Sweden from January 1, 1998, followed from their 14th birthday or arrival to Sweden, until death, emigration, or December 31, 2016. People with ICD-10 psychotic disorder (F20–33; N = 9399) were 6.7 (95% confidence interval [95%CI]: 5.9–7.6) times more likely to die than the general population, but this did not vary by migrant status (P = .15) or region-of-origin (P = .31). This mortality gap was most pronounced for suicide (adjusted hazard ratio [aHR]: 12.2; 95% CI: 10.4–14.4), but persisted for deaths from other external (aHR: 5.1; 95%CI: 4.0–6.4) and natural causes (aHR: 2.3; 95%CI: 1.6–3.3). Non-refugee (adjusted odds ratio [aOR]: 1.4, 95%CI: 1.2–1.6) and refugee migrants (aOR: 1.4, 95%CI: 1.1–1.8) were more likely to receive inpatient care at first diagnosis. No differences in in-patient LOS at first diagnosis were observed by migrant status. Sub-Saharan African migrants with psychotic disorder were readmitted more quickly than their Swedish-born counterparts (adjusted sub-hazard ratio [sHR]: 1.2; 95%CI: 1.1–1.4). Our findings highlight the need to understand the drivers of disparities in psychosis treatment and the mortality gap experienced by all people with disorder, irrespective of migrant status or region-of-origin.
Pericyte‐like cells undergo transcriptional reprogramming and distinct functional adaptations in acute lung injury
Authors: Hung Chi F. , Holton Sarah , Chow Yu‐Hua , Liles Wayne Conrad , Gharib Sina A. , Altemeier William A.
Published: March 2021

We previously reported on the role of pericyte‐like cells as functional sentinel immune cells in lung injury. However, much about the biological role of pericytes in lung injury remains unknown. Lung pericyte‐like cells are well‐positioned to sense disruption to the epithelial barrier and coordinate local inflammatory responses due to their anatomic niche within the alveoli. In this report, we characterized transcriptional responses and functional changes in pericyte‐like cells following activation by alveolar components from injured and uninjured lungs in a mouse model of acute lung injury (ALI). Purified pericyte‐like cells from lung digests using PDGFRβ as a selection marker were expanded in culture as previously described (1). We induced sterile acute lung injury in mice with recombinant human Fas ligand (rhFasL) instillation followed by mechanical ventilation (1). We then collected bronchoalveolar lavage fluid (BALF) from injured and uninjured mice. Purified pericyte‐like cells in culture were exposed to growth media only (control), BALF from uninjured mice, and BALF from injured mice for 6 and 24 hours. RNA collected from these treatment conditions were processed for RNAseq. Targets of interest identified by pathway analysis were validated using in vitro and in vivo assays. We observed robust global transcriptional changes in pericyte‐like cells following treatment with uninjured and injured BALF at 6 hours, but this response persisted for 24 hours only after exposure to injured BALF. Functional enrichment analysis of pericytes treated with injured BALF revealed the activation of pro‐inflammatory, cell migration, and angiogenesis‐related pathways, whereas processes associated with tissue development and cell differentiation were down‐regulated. We validated select upregulated targets in the inflammatory, angiogenic, and cell migratory pathways using functional biological assays in vitro and in vivo. We conclude that lung pericyte‐like cells are highly responsive to alveolar compartment content from both uninjured and injured lungs, but injured BALF elicits a more sustained response. The inflammatory, angiogenic, and migratory changes exhibited by activated pericyte‐like cells underscore the phenotypic plasticity of these specialized stromal cells in the setting of acute lung injury.
Pyrroloquinoline quinone protects against exercise‐induced fatigue and oxidative damage via improving mitochondrial function in mice
Authors: Liu Lixia , Zhang Yingyong , Liu Tao , Ke Chongrong , Huang Jianzhong , Fu Yajuan , Lin Zhang , Chen Fengjuan , Wu Xiuqin , Chen Qi
Published: March 2021

Pyrroloquinoline quinone (PQQ) has a variety of biological functions. However, rare attention has been paid to its effects on exercise‐induced damage. Here, we assessed the potential protective effects of PQQ against the fatigue and oxidative damage caused by repeated exhaustive exercise, and studied the underlying mechanism. The models for exercise‐induced fatigue were established, and the parameters were measured, including the time to exhaustion (TTE), biochemical indicators, the expression of nuclear factor kappa B (NF‐κB) and inflammatory cytokines and so on. Besides, the mitochondrial function was evaluated by the morphology, membrane potential, respiratory function, adenosine triphosphate (ATP) levels, and the application of the mitochondrial complex I inhibitor. The results demonstrate that PQQ prolongs TTE, causes the decrease in the activity of serum creatine kinase and lactate dehydrogenase, increases the activity of antioxidant enzymes, inhibits the production of reactive oxygen species (ROS) and malondialdehyde (MDA), and diminishes the over expression of NF‐κB (p65) and inflammatory mediators. Furthermore, PQQ preserves normal mitochondrial function. Particularly, PQQ reduces the accumulation of ROS triggered by the mitochondrial complex I inhibitor. These data suggest that PQQ can significantly protect mice from exercise‐induced fatigue and oxidative damage by improving mitochondrial function. These data also suggest that PQQ controls mitochondrial activity through directly affecting the NADH dehydrogenase.