bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical framework for the emergent floe size distribution in the marginal ice zone: the case for log-normality
Authors: Montiel Fabien , Mokus Nicolas 
Published: September 2022

Sea ice is not horizontally homogeneous on large scales. Its morphology is inherently discrete and made of individual floes. In recent years, sea ice models have incorporated this horizontal heterogeneity. The modelling framework considers an evolution equation for the probability density function of the floe size distribution (FSD) with forcing terms that represent the effects of several physical processes. Despite the modelling effort, a key question remains: What is the FSD emerging from the collection of all forcing processes? Field observations have long suggested that the FSD follows a power law, but this result has not been reproduced by models or laboratory experiments. The theoretical framework for FSD dynamics in response to physical forcings is presented. Wave-induced breakup is further examined with an emphasis on how it affects the FSD. Recent modelling results suggesting the consistent emergence of a log-normal distribution as a result of that process are further discussed. Log-normality is also found in a dataset of floe sizes, which was originally analysed under the power law hypothesis. A simple stochastic process of FSD dynamics, based on random fragmentation theory, is further shown to predict log-normality. We therefore conjecture that, in some situations, the emergent FSD follows a log-normal distribution.This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.
Multi-scale satellite observations of Arctic sea ice: new insight into the life cycle of the floe size distribution
Authors: Hwang Byongjun , Wang Yanan 
Published: September 2022

This study provides a new conceptional framework to understand the life cycle of the floe size distribution of Arctic sea ice and the associated processes. We derived the floe size distribution from selected multi-scale satellite imagery data acquired from different locations and times in the Arctic. Our study identifies three stages of the floe size evolution during summer – ‘fracturing’, ‘transition’ and ‘melt/wave fragmentation’. Fracturing defines the initial floe size distribution (
N
∼

d
−α

, where
d
is floe size) formed from the spring breakup, characterized by the single power-law regime over
d
= 30–3000 m with
α

≈

2. The initial floe size distribution is then modified by various floe fragmentation processes during the transition period, which is characterized by ‘selective’ fragmentation of large floes (
d
> 200–300 m) with variable
α
= 2.5–3.5 depending on the degree of fragmentation. As ice melt intensifies, the melt fragmentation expands the single power-law regime into smaller floes (
d
= 70 m) with
α
= 2.4–3.8, while a significant reduction of small floes (
d
< 30–40 m) occurs due to lateral melt. The shape factor shows an overall progression from elongated floes into rounded floes. The effects of scaling and wave-fracture are also discussed.

This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.
A model study of convergent dynamics in the marginal ice zone
Authors: Auclair Jean-Pierre , Dumont Dany , Lemieux Jean-François , Ritchie Hal 
Published: September 2022

With the increasing resolution of operational forecasting models, the marginal ice zone (MIZ), the area where waves and sea ice interact, can now be better represented. However, the proper mechanics of wave propagation and attenuation in ice, and especially their influence on sea ice dynamics, still remain poorly understood and constrained in models. Observations have shown exponential wave energy decrease with distance in sea ice, particularly strong at higher frequencies. Some of this energy is transferred to the ice, breaking it into smaller floes and weakening it, as well as exerting a stress on the ice similar to winds and currents. In this article, we present a one-dimensional, fully integrated wave and ice model that has been developed to test different parameterizations of wave–ice interactions. The response of the ice cover to the wind and wave radiative stresses is investigated for a variety of wind, wave and ice conditions at different scales. Results of sensitivity analyses reveal the complex interplay between wave attenuation and rheological parameters and suggest that the compressive strength of the MIZ may be better represented by a Mohr-Coulomb parameterization with a nonlinear dependence on thickness.
This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.
Marginal ice zone dynamics: future research perspectives and pathways
Authors: Bennetts L. G. , Bitz C. M. , Feltham D. L. , Kohout A. L. , Meylan M. H. 
Published: September 2022

Perspectives are discussed on future directions for the field of marginal ice zone (MIZ) dynamics, based on the extraordinary progress made over the past decade in its theory, modelling and observations. Research themes are proposed that would shift the field’s focus towards the broader implications of MIZ dynamics in the climate system. In particular, pathways are recommended for research that highlights the impacts of trends in the MIZ on the responses of Arctic and Antarctic sea ice to climate change.
This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.
LEAF- 4L6715 enhances oxygenation in patients with acute respiratory distress syndrome (ARDS) due to severe COVID-19: Final results of a phase I/II clinical trial
Authors: Mertes Paul-Michel , Delabranche Xavier , Coliat Pierre , Roche Anne , Collange Olivier , Voegelin Manon , Bernard Alexandre , Dhindsa Navreet , Xu Zhenghong Hannah , Geng Bolin , Niyikiza Clet , Moyo Victor , Bourban Claire , Villa Pascal , Detappe Alexandre , Pivot Xavier 
Published: September 2022

AbstractLEAF-4L6715 is a liposomal formulation encapsulating transcrocetin (TC) developed to enhance the diffusion of oxygen in the body. Here, we report the final results of the phase I/II clinical trial (NCT04378920; EUDRACT2020–001393–30) initiated to identify an optimal regimen and to assess the activity of TC in the context of acute respiratory distress syndrome (ARDS). More specifically, LEAF-4L6715 was developed to treat patients with ARDS due to severe SARS-CoV-2 infection who have a ratio of partial arterial pressure to inspired fraction of oxygen (PaO2/FiO2 ratio) <200 treated with artificial ventilation support in an intensive care unit.A total of 37 patients were treated (across 6 dosing cohorts) with LEAF-4L6715 given as an intravenous infusion for over 90 minutes. The dose of LEAF-4L6715 was increased until the transaminase levels were elevated and 4 grade 3 events occurred among 8 patients. The recommended dosage was determined to be a fixed concentration of 300 mg administered every 12 hours. An improvement in the PaO2/FiO2 ratio and SOFA score was observed. The overall 28-day survival rate of 81%.This study identified the recommended dose for LEAF 4L6715 and the dose-limiting toxicity and showed an overall favorable risk/benefit profile. These preliminary findings are promising for the activity of LEAF-4L6715 but will require confirmation in a randomized phase III trial.
Comparison of visual quantities in untrained deep neural networks
Authors: Lee Hyeonsu , Choi Woochul , Lee Dongil , Paik Se-Bum 
Published: September 2022

AbstractThe ability to compare quantities of visual objects with two distinct measures, proportion and difference, is observed in newborn animals. Nevertheless, how this function originates in the brain, even before training, remains unknown. Here, we show that neuronal tuning for quantity comparison can arise spontaneously in completely untrained deep neural networks. Using a biologically inspired model neural network, we found that units selective to proportions and differences between visual quantities emerge in randomly initialized networks and that they enable the network to perform quantity comparison tasks. Further analysis shows that two distinct tunings to proportion and difference both originate from a random summation of monotonic, nonlinear responses to changes in relative quantities. Notably, we found that a slight difference in the nonlinearity profile determines the type of measure. Our results suggest that visual quantity comparisons are primitive types of functions that can emerge spontaneously in random feedforward networks.One sentence summaryThe ability to compare visual quantities arises spontaneously in untrained deep neural networks.Research HighlightsThe ability to compare visual quantity arises spontaneously in untrained networksDistinct tunings to measure proportion and difference of quantities are observedRandom wiring of monotonic, nonlinear activity induces quantity-comparison unitsThe nonlinearity pattern of the source unit determines the type of target measure
Neuronal mitochondrial morphology is significantly affected by both fixative and oxygen level during perfusion
Authors: Kim Su Yeon , Strucinska Klaudia , Osei Bertha , Han Kihoon , Kwon Seok-Kyu , Lewis Tommy L. 
Published: September 2022

ABSTRACTNeurons in the brain have a uniquely polarized structure consisting of multiple dendrites and a single axon generated from a cell body. Interestingly, intracellular mitochondria also show strikingly polarized morphologies along the dendrites and axons: in cortical pyramidal neurons (PNs) dendritic mitochondria have a long and tubular shape, while axonal mitochondria are small and circular. Mitochondria play important roles in each compartment of the neuron by generating ATP and buffering calcium, thereby affecting synaptic transmission and neuronal development. In addition, mitochondrial shape, and thereby function, is dynamically altered by environmental stresses such as oxidative stress, or in various neurodegenerative diseases including Alzheimer’s disease and Parkinson’s disease. Although the importance of altered mitochondrial shape has been claimed by multiple studies, methods for studying this stress-sensitive organelle have not been standardized. Here we address the pertinent steps that influence mitochondrial morphology during experimental processes. We demonstrate that fixative solutions containing only paraformaldehyde (PFA), or that introduce hypoxic conditions during the procedure induce dramatic fragmentation of mitochondria both in vitro and in vivo. This disruption was not observed following the use of glutaraldehyde addition or oxygen supplementation, respectively. Finally, using pre-formed fibril α-synuclein treated neurons, we show a difference between mitochondrial morphology when samples were fixed with PFA/glutaraldehyde or PFA/sucrose containing solutions, but not PFA alone. Our study provides optimized methods for examining mitochondrial morphology in neurons, and demonstrates that fixation conditions are critical when investigating the underlying cellular mechanisms involving mitochondria in physiological and neurodegenerative disease models.
Olfactory responses of Drosophila suzukii parasitoids to chemical cues from SWD-infested fruit
Authors: Triñanes F. , González A. , de la Vega G. J. 
Published: September 2022

AbstractSince Drosophila suzukii (Diptera: Drosophilidae; SWD) became a worldwide pest of soft-skinned fruits, multiple mitigation strategies alternative to insecticides have been explored. Among these, the search for biological control agents has prompted the assessment of drosophilid parasitoids for SWD control. Olfactometer bioassays with drosophilid parasitoids have shown that host substrate-related complex olfactory cues are relevant during host search. No information is available, however, on which fruit volatiles may be used as host-related cues. Here, we used gas chromatography coupled to electroantennography (GC-EAD) to evaluate the antennal detection of ecologically relevant fruit odours by two drosophillid parasitoids, Leptopilina boulardi (Hymenoptera: Figitidae) and Trichopria anastrephae (Hymenoptera: Diapriidae). We found that females of both wasp species are capable of detecting the main volatile compounds emitted by SWD-infested strawberries, five and ten days after oviposition by SWD females. The EAD-active fruit compounds were identified by GC-MS analysis as the common fruit esters ethyl butanoate, methyl hexanoate and ethyl hexanoate. The relative proportions of these fruit esters vary over time, with potential ecological significant for larval and pupal parasitoids. Our study is the first to report GC-EAD responses of microhymenopteran wasps of drosophilid flies. Understanding the sensory ecology of host-related chemical cues may be useful to optimize the biological control of D. suzukii by parasitoid wasps.
Assessing the risk stratification of breast cancer polygenic risk scores in two Brazilian samples
Authors: Barreiro R.A.S , Almeida TF , Gomes CS , Monfardini F , Farias AA , Tunes GC , Souza GM , Duim E , Correia JS , Coelho AVC , Caraciolo MP , Duarte YAO , Zatz M , Amaro E , Oliveira JB , Bitarello BD , Brentani H , Naslavsky MS 
Published: September 2022

ABSTRACTPolygenic risk scores (PRS) for breast cancer (BC) have a clear clinical utility in risk prediction. PRS transferability across populations and ancestry groups is hampered by population-specific factors, ultimately leading to differences in variant effects, such as linkage disequilibrium (LD) and differences in variant frequency (AF-diff). Thus, locally-sourced population-based phenotypic and genomic datasets are essential to assess the validity of PRS derived from signals detected across populations. Here, assess the transferability of a BC PRS composed of 313 risk variants (313-PRS) in two Brazilian tri-hybrid admixed ancestries (European, African and Native American) whole-genome sequenced cohorts. We computed 313-PRS in both cohorts (n=753 and n=853) versus the UK Biobank (UKBB, n=264,307) as reference. We show that although the Brazilian cohorts have a high European (EA) component, with AF-diff and to a lesser extent LD patterns like those found in EA populations, the 313-PRS distribution is inflated when compared to that of the UKBB, leading to potential overestimation of PRS-based risk if EA is taken as a standard. Interestingly, we find that case-controls lead to equivalent predictive power when compared to UKBB-EA samples with AUROC values of 0.66-0.62 compared to 0.63 for UKBB.
Decomposing Interaction and Mediating Effects of Race/Ethnicity and Circulating Cystatin C on Cognitive Status in the United States Health and Retirement Study
Authors: Higgins Cesar , Ware Erin B. , Kobayashi Lindsay C. , Fu Mingzhou , Hicken Margaret , Zawistowski Matthew , Mukherjee Bhramar , Bakulski Kelly M. 
Published: September 2022

AbstractBackground and objectivesElevated circulating cystatin C is associated with cognitive impairment in non-Hispanic Whites, but its role in racial disparities in dementia is understudied. In a nationally representative sample of older non-Hispanic White, non-Hispanic Black, and Hispanic adults in the United States, we use mediation-interaction analysis to understand how racial disparities in the cystatin C physiological pathway may contribute to racial disparities in prevalent dementia.MethodsIn a pooled cross-sectional sample of the Health and Retirement Study (n=9,921), we employed Poisson regression to estimate prevalence ratios and to test the relationship between elevated cystatin C (>1.24mg/L versus <1.24mg/L) and impaired cognition, adjusted for demographics, behavioral risk factors, and other biomarkers. Self-reported racialized social categories were a proxy measure for exposure to racism. We calculated additive interaction measures and conducted four-way mediation-interaction decomposition analysis to test the moderating effect of race/ethnicity and mediating effect of cystatin C on the racial disparity.ResultsOverall, elevated cystatin C was associated with dementia (prevalence ratio [PR] = 1.4; 95%CI: 1.2, 1.8). Among non-Hispanic Black relative to non-Hispanic White participants, the relative excess risk due to interaction was 1.7 (95% CI: -0.2, 3.7), the attributable proportion was 0.2 (95%CI: 0.0, 0.5), and the synergy index was 1.4 (95% CI: 1.0, 2.0) in a fully-adjusted model. Elevated cystatin C was estimated to account for 2% (95% CI: -0%, 4%) for the racial disparity in prevalent dementia, and the interaction accounted for 9% (95% CI: -4%, 23%). Analyses for Hispanic relative to non-White participants suggested moderation by race/ethnicity, but not mediation.DiscussionElevated cystatin C was associated with dementia prevalence. Our mediation-interaction decomposition analysis suggested that the effect of elevated cystatin C on the racial disparity might be moderated by race/ethnicity, which indicates that the racialization process affects not only the distribution of circulating cystatin C across minoritized racial groups, but also the strength of association between the biomarker and dementia prevalence. These results provide evidence that cystatin C is associated with adverse brain health and this effect is larger than expected for individuals racialized as minorities had they been racialized and treated as non-Hispanic White.
Developmental role of macrophages modelled in human pluripotent stem cell derived intestinal tissue
Authors: Song Andrew T. , Sindeaux Renata H. M. , Li Yuanyi , Affia Hicham , Agnihotri Tapan , Leclerc Severine , van Vliet Patrick Piet , Colas Mathieu , Guimond Jean-Victor , Patey Natasha , Joyal Jean-Sebastien , Haddad Elie , Barreiro Luis , Andelfinger Gregor 
Published: September 2022

SummaryMacrophages populate the embryo early in gestation but their role in the developmental process remains largely unknown. In particular, specification and function of macrophages in intestinal development remain unexplored. To study this event in human developmental context, we derived and combined human intestinal organoid and macrophages from pluripotent stem cells. Macrophages migrated into the organoid, proliferated, and occupied the emerging micro-anatomical niches of epithelial crypts and ganglia. They also acquired a similar transcriptomic profile to fetal intestinal macrophages and displayed tissue macrophage behaviors, such as recruitment to tissue injury. Using this model, we show that macrophages reduce glycolysis in mesenchymal cells and limit tissue growth without affecting tissue architecture, in contrast to the pro-growth effect of enteric neurons. In short, we engineered an intestinal tissue model populated with macrophages, and we suggest that resident macrophages contribute to regulation of metabolism and growth of the developing intestine.
Examining Litter Specific Variability in Mice and its Impact on Neurodevelopmental Studies
Authors: Valiquette Vanessa , Guma Elisa , Cupo Lani , Gallino Daniel , Anastassiadis Chloe , Snook Emily , Devenyi Gabriel A. , Chakravarty M. Mallar 
Published: September 2022

AbstractOur current understanding of litter variability in neurodevelopmental studies using mouse may limit translation of neuroscientific findings. Higher variance of measures across litters than within, often termed intra-litter likeness, may be attributable to pre- and postnatal environment. This study aimed to assess the litter-effect within behavioral assessments (2 timepoints), and anatomy using T1-weighted magnetic resonance images (4 timepoints) across 72 brain region volumes (36 C57bl/6J inbred mice; 7 litters: 19F/17M). Between-litter comparisons of brain and behavioral measures and their associations were evaluated using univariate and multivariate techniques. A power analysis using simulation methods was then performed modeling neurodevelopment and evaluating trade-offs between number-of-litters, mice-per-litter, and sample size. Our results show litter-specific developmental effects, from the adolescent period to adulthood for brain structure volumes and behaviors, and their associations in adulthood. Our power simulation analysis results suggest increasing the number-of-litters in experimental design to achieve the smallest total sample size for detecting different rates of change in specific brain regions. Our results also demonstrate how litter-specific effects may influence development and that increasing the litters to the total sample size ratio should be strongly considered when designing neurodevelopmental studies.
Contractile ring mechanosensation and its anillin-dependent tuning during early embryogenesis
Authors: Hsu Christina Rou , Sangha Gaganpreet , Fan Wayne , Zheng Joey , Sugioka Kenji 
Published: September 2022

AbstractThe contractile ring plays crucial roles in animal morphogenesis. Previous studies have explored how tissue mechanics controls the contractile ring; however, the mechanisms by which the ring senses tissue mechanics remain largely unknown. Here, we demonstrate the mechanism of contractile ring mechanosensation and its tuning during asymmetric ring closure ofCaenorhabditis elegansembryos. High-resolution imaging of cortical flow revealed that local suppression of the ring-directed cortical flow is associated with a delay in furrowing. This suppression of cortical flow results from cortical compression. We found that the artificial inhibition of ring-directed cortical flow was sufficient to induce asymmetric ring closure in symmetrically dividing cells. Moreover, genetic analysis suggests that the positive feedback loop among ring-directed cortical flow, myosin enrichment, and ring constriction constitutes the anillin-dependent, mechanosensitive engine driving asymmetric ring closure. Our results suggest that the balance between RhoA-dependent and cortical flow-dependent myosin enrichment fine-tunes the ring’s mechanosensitivity in tissues.