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Stem cells give rise to the entirety of cells within an organ. Maintaining stem cell identity and coordinately regulating stem cell divisions is crucial for proper development. In plants, mobile proteins, such as WUSCHEL-RELATED HOMEOBOX 5 (WOX5) and SHORTROOT (SHR), regulate divisions in the root stem cell niche. However, how these proteins coordinately function to establish systemic behaviour is not well understood. We propose a non-cell autonomous role for WOX5 in the cortex endodermis initial (CEI) and identify a regulator, ANGUSTIFOLIA (AN3)/GRF-INTERACTING FACTOR 1, that coordinates CEI divisions. Here, we show with a multi-scale hybrid model integrating ordinary differential equations (ODEs) and agent-based modeling that quiescent center (QC) and CEI divisions have different dynamics. Specifically, by combining continuous models to describe regulatory networks and agent-based rules, we model systemic behaviour, which led us to predict cell-type-specific expression dynamics of SHR, SCARECROW, WOX5, AN3 and CYCLIND6;1, and experimentally validate CEI cell divisions. Conclusively, our results show an interdependency between CEI and QC divisions.
Catheter ablation is a safe and effective therapy for the treatment of supraventricular tachycardia in children. Current improvements in technology have allowed progressive reduction in radiation exposure associated with the procedure. To assess the impact of three-dimensional mapping, we compared acute procedural results collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to published results from the Prospective Assessment after Pediatric Cardiac Ablation study.
Inclusion and exclusion criteria from the Prospective Assessment after Pediatric Cardiac Ablation study were used as guidelines to select patient data from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to compare acute procedural outcomes between cohorts. Outcomes assessed include procedural and fluoroscopy exposure times, success rates of procedure, and complications.
In 786 ablation procedures, targeting 498 accessory pathways and 288 atrioventricular nodal reentrant tachycardia substrates, average procedural time (156.5 versus 206.7 minutes, p < 0.01), and fluoroscopy time (1.2 versus 38.3 minutes, p < 0.01) were significantly shorter in the study group. Success rates for the various substrates were similar except for manifest accessory pathways which had a significantly higher success rate in the study group (96.4% versus 93.0%, p < 0.01). Major complication rates were significantly lower in the study group (0.3% versus 1.6%, p < 0.01).
In a large, multicentre study, three-dimensional systems show favourable improvements in clinical outcomes in children undergoing catheter ablation of supraventricular tachycardia compared to the traditional fluoroscopic approach. Further improvements are anticipated as technology advances.
Sleep and circadian timing shifts later during adolescence, conflicting with early school start times, and resulting in circadian misalignment. Although circadian misalignment has been linked to depression, substance use, and altered reward function, a paucity of experimental studies precludes the determination of causality. Here we tested, for the first time, whether experimentally-imposed circadian misalignment alters the neural response to monetary reward and/or response inhibition.
Healthy adolescents (n = 25, ages 13–17) completed two in-lab sleep schedules in counterbalanced order: An ‘aligned’ condition based on typical summer sleep-wake times (0000–0930) and a ‘misaligned’ condition mimicking earlier school year sleep-wake times (2000–0530). Participants completed morning and afternoon functional magnetic resonance imaging scans during each condition, including monetary reward (morning only) and response inhibition (morning and afternoon) tasks. Total sleep time and circadian phase were assessed via actigraphy and salivary melatonin, respectively.
Bilateral ventral striatal (VS) activation during reward outcome was lower during the Misaligned condition after accounting for the prior night's total sleep time. Bilateral VS activation during reward anticipation was lower during the Misaligned condition, including after accounting for covariates, but did not survive correction for multiple comparisons. Right inferior frontal gyrus activation during response inhibition was lower during the Misaligned condition, before and after accounting for total sleep time and vigilant attention, but only during the morning scan.
Our findings provide novel experimental evidence that circadian misalignment analogous to that resulting from school schedules may have measurable impacts on healthy adolescents' reward processing and inhibition of prepotent responses.
The Promontory caves (Utah) and Franktown Cave (Colorado) contain high-fidelity records of short-term occupations by groups with material culture connections to the Subarctic/Northern Plains. This research uses Promontory and Franktown bison dung, hair, hide, and bone collagen to establish local baseline carbon isotopic variability and identify leather from a distant source. The ankle wrap of one Promontory Cave 1 moccasin had a δ13C value that indicates a substantial C4 component to the animal's diet, unlike the C3 diets inferred from 171 other Promontory and northern Utah bison samples. We draw on a unique combination of multitissue isotopic analysis, carbon isoscapes, ancient DNA (species and sex identification), tissue turnover rates, archaeological contexts, and bison ecology to show that the high δ13C value was not likely a result of local plant consumption, bison mobility, or trade. Instead, the bison hide was likely acquired via long-distance travel to/from an area of abundant C4 grasses far to the south or east. Expansive landscape knowledge gained through long-distance associations would have allowed Promontory caves inhabitants to make well-informed decisions about directions and routes of movement for a territorial shift, which seems to have occurred in the late thirteenth century.
When presenting with a first episode of psychosis (FEP), migrants can have different demographic and clinical characteristics to the native-born population and this was examined in an Irish Early Intervention for Psychosis service.
All cases of treated FEP from three local mental health services within a defined catchment area were included. Psychotic disorder diagnoses were determined using the SCID and symptom and functioning domains were measured using validated and reliable measures.
From a cohort of 612 people, 21.1% were first-generation migrants and there was no difference in the demographic characteristics, diagnoses, symptoms or functioning between migrants and those born in the Republic of Ireland, except that migrants from Africa presented with less insight. Of those admitted, 48.6% of admissions for migrants were involuntary compared to 37.7% for the native-born population (p = 0.09).
First-generation migrants now make up a significant proportion of people presenting with a FEP to an Irish EI for psychosis service. Broadly the demographic and clinical characteristics of migrants and those born in the Republic of Ireland are similar, except for less insight in migrants from Africa and a trend for a higher proportion of involuntary admissions in the total migrant group.
To examine rural–urban differences in temporal trends and risk of inappropriate antibiotic use by agent and duration among women with uncomplicated urinary tract infection (UTI).
Observational cohort study.
Using the IBM MarketScan Commercial Database (2010–2015), we identified US commercially insured women aged 18–44 years coded for uncomplicated UTI and prescribed an oral antibiotic agent. We classified antibiotic agents and durations as appropriate versus inappropriate based on clinical guidelines. Rural–urban status was defined by residence in a metropolitan statistical area. We used modified Poisson regression to determine the association between rural–urban status and inappropriate antibiotic receipt, accounting for patient- and provider-level characteristics. We used multivariable logistic regression to estimate trends in antibiotic use by rural–urban status.
Of 670,450 women with uncomplicated UTI, a large proportion received antibiotic prescriptions for inappropriate agents (46.7%) or durations (76.1%). Compared to urban women, rural women were more likely to receive prescriptions with inappropriately long durations (adjusted risk ratio 1.10, 95% CI, 1.10–1.10), which was consistent across subgroups. From 2011 to 2015, there was slight decline in the quarterly proportion of patients who received inappropriate agents (48.5% to 43.7%) and durations (78.3% to 73.4%). Rural–urban differences varied over time by agent (duration outcome only), geographic region, and provider specialty.
Inappropriate antibiotic prescribing is quite common for the treatment of uncomplicated UTI. Rural women are more likely to receive inappropriately long antibiotic durations. Antimicrobial stewardship interventions are needed to improve outpatient UTI antibiotic prescribing and to reduce unnecessary exposure to antibiotics, particularly in rural settings.
Structural models of psychopathology consistently identify internalizing (INT) and externalizing (EXT) specific factors as well as a superordinate factor that captures their shared variance, the p factor. Questions remain, however, about the meaning of these data-driven dimensions and the interpretability and distinguishability of the larger nomological networks in which they are embedded.
The sample consisted of 10 645 youth aged 9–10 years participating in the multisite Adolescent Brain and Cognitive Development (ABCD) Study. p, INT, and EXT were modeled using the parent-rated Child Behavior Checklist (CBCL). Patterns of associations were examined with variables drawn from diverse domains including demographics, psychopathology, temperament, family history of substance use and psychopathology, school and family environment, and cognitive ability, using instruments based on youth-, parent-, and teacher-report, and behavioral task performance.
p exhibited a broad pattern of statistically significant associations with risk variables across all domains assessed, including temperament, neurocognition, and social adversity. The specific factors exhibited more domain-specific patterns of associations, with INT exhibiting greater fear/distress and EXT exhibiting greater impulsivity.
In this largest study of hierarchical models of psychopathology to date, we found that p, INT, and EXT exhibit well-differentiated nomological networks that are interpretable in terms of neurocognition, impulsivity, fear/distress, and social adversity. These networks were, in contrast, obscured when relying on the a priori Internalizing and Externalizing dimensions of the CBCL scales. Our findings add to the evidence for the validity of p, INT, and EXT as theoretically and empirically meaningful broad psychopathology liabilities.
We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding of Earth's sensitivity to carbon dioxide, finds that permafrost thaw could release more carbon emissions than expected and that the uptake of carbon in tropical ecosystems is weakening. Adverse impacts on human society include increasing water shortages and impacts on mental health. Options for solutions emerge from rethinking economic models, rights-based litigation, strengthened governance systems and a new social contract. The disruption caused by COVID-19 could be seized as an opportunity for positive change, directing economic stimulus towards sustainable investments.
A synthesis is made of ten fields within climate science where there have been significant advances since mid-2019, through an expert elicitation process with broad disciplinary scope. Findings include: (1) a better understanding of equilibrium climate sensitivity; (2) abrupt thaw as an accelerator of carbon release from permafrost; (3) changes to global and regional land carbon sinks; (4) impacts of climate change on water crises, including equity perspectives; (5) adverse effects on mental health from climate change; (6) immediate effects on climate of the COVID-19 pandemic and requirements for recovery packages to deliver on the Paris Agreement; (7) suggested long-term changes to governance and a social contract to address climate change, learning from the current pandemic, (8) updated positive cost–benefit ratio and new perspectives on the potential for green growth in the short- and long-term perspective; (9) urban electrification as a strategy to move towards low-carbon energy systems and (10) rights-based litigation as an increasingly important method to address climate change, with recent clarifications on the legal standing and representation of future generations.
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Stronger permafrost thaw, COVID-19 effects and growing mental health impacts among highlights of latest climate science.
Cardiovascular diseases (CVD) are important consequences of adverse perinatal conditions such as fetal hypoxia and maternal malnutrition. Cardiac magnetic resonance imaging (CMR) can produce a wealth of physiological information related to the development of the heart. This review outlines the current state of CMR technologies and describes the physiological biomarkers that can be measured. These phenotypes include impaired ventricular and atrial function, maladaptive ventricular remodeling, and the proliferation of myocardial steatosis and fibrosis. The discussion outlines the applications of CMR to understanding the developmental pathways leading to impaired cardiac function. The use of CMR, both in animal models of developmental programming and in human studies, is described. Specific examples are given in a baboon model of intrauterine growth restriction (IUGR). CMR offers great potential as a tool for understanding the sequence of dysfunctional adaptations of developmental origin that can affect the human cardiovascular system.
This essay argues that social theory, and social science per se, must be reconstructed to address a rapidly emergent planetary crisis characterized by exceptional ecological degradation and extreme economic inequality. The task requires re-envisioning society as part of the interdependent “web of nature,” acknowledging that humans face ecological constraints like all other living things with which we share the planet, grasping the growth imperative for capital accumulation as the primary driver of the socioecological crisis, and coming to terms with the need to radically transform capitalism as we have known it to escape catastrophe.
Robert J. Antonio teaches sociology at the University of Kansas. He specializes in social theory, but also works on globalization, political economy, and the environment. Currently he is working on projects related to capitalism’s crisis tendencies, especially concerning the intersection of increased economic inequality, ecological risk, and democratic and authoritarian responses.
Brett Clark is Professor of Sociology, Environmental Humanities, and Environmental and Sustainability Studies at the University of Utah. His research interests include social theory, political economy, and ecology.
Optical tracking systems typically trade off between astrometric precision and field of view. In this work, we showcase a networked approach to optical tracking using very wide field-of-view imagers that have relatively low astrometric precision on the scheduled OSIRIS-REx slingshot manoeuvre around Earth on 22 Sep 2017. As part of a trajectory designed to get OSIRIS-REx to NEO 101955 Bennu, this flyby event was viewed from 13 remote sensors spread across Australia and New Zealand to promote triangulatable observations. Each observatory in this portable network was constructed to be as lightweight and portable as possible, with hardware based off the successful design of the Desert Fireball Network. Over a 4-h collection window, we gathered 15 439 images of the night sky in the predicted direction of the OSIRIS-REx spacecraft. Using a specially developed streak detection and orbit determination data pipeline, we detected 2 090 line-of-sight observations. Our fitted orbit was determined to be within about 10 km of orbital telemetry along the observed 109 262 km length of OSIRIS-REx trajectory, and thus demonstrating the impressive capability of a networked approach to Space Surveillance and Tracking.
Richard Price (1723–91) is important in present-day historiography chiefly for the interpretation of two great revolutions, the American and the French. Recent studies have depicted him as insightfully forward-looking, a well-informed cosmopolitan, his thought providing an interpretive key to the Age of Revolutions, and so as a landmark figure of a singular Enlightenment. They have paid insufficient attention to his identity as a theologian, a Welsh-born Nonconformist minister of more defined outlook, spending his life in England and campaigning above all for the relief of Nonconformist grievances, picturing “tyranny” and “superstition” in conventional Nonconformist terms. This article offers a reconsideration of the significance of such a Price for the historical understanding of two major and (it contends) related problems: how did the American Revolution relate to the French in a supposed Age of Revolutions, and how should they be understood as putative episodes in the development of the Enlightenment?
Much remains unknown about how the 2008 Great Recession, coupled with the ageing baby-boomer cohort, have shaped retirement expectations and realised retirement timing across diverse groups of older Americans. Using the Health and Retirement Study (1992–2016), we compared expectations about full-time work at age 62 (reported at ages 51–61) with realised labour force status at age 62. Of the 12,049 respondents, 34 per cent reported no chance of working full time at 62 (zero probability) and 21 per cent reported it was very likely (90–100 probability). Among those reporting no chance of working, there was a 0.111 probability of unmet expectations; among those with high expectations of working, there was a 0.430 probability of unmet expectations. Black and Hispanic Americans were more likely than white Americans to have unmet expectations of both types. Educational attainment was associated with higher probability of unexpectedly working and lower probability of unexpectedly not working. Baby-boomers experienced fewer unmet expectations than prior cohorts but more uncertainty about work status at 62. Our findings highlight the unpredictability of retirement timing for significant segments of the US population and the role of the Great Recession in contributing to uncertainty. Given the individual and societal benefits of long work lives, special attention should be paid to the high rates of unexpectedly not working at age 62.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
It has been widely speculated that dominant motifs, such as short-range icosahedral order, can influence glass formation and the properties of glasses. Experimental data on both fragile and strong undercooled liquids show corresponding changes in their thermophysical properties consistent with increasing development of a network of interconnect motifs based on molecular dynamics. Describing these regions of local order, how they connect, and how they are related to property changes have been challenging issues, both computationally and experimentally. Yet the consensus is that metallic liquids develop interconnected medium-range order consisting of some regions with lower mobility with deeper undercooling. Less well understood is how these motifs (or “crystal genes”) in the liquid can inhibit nucleation in the deeply undercooled liquid or influence phase selection upon devitrification. These motifs tend to have local packing unlike stable compounds with icosahedral order tending to dominate the best glass formers. The underlying kinetic and thermodynamic forces that guide the formation of these motifs and how they interconnect during undercooling remain open questions.
Through diversity of composition, sequence, and interfacial structure, hybrid materials greatly expand the palette of materials available to access novel functionality. The NSF Division of Materials Research recently supported a workshop (October 17–18, 2019) aiming to (1) identify fundamental questions and potential solutions common to multiple disciplines within the hybrid materials community; (2) initiate interfield collaborations between hybrid materials researchers; and (3) raise awareness in the wider community about experimental toolsets, simulation capabilities, and shared facilities that can accelerate this research. This article reports on the outcomes of the workshop as a basis for cross-community discussion. The interdisciplinary challenges and opportunities are presented, and followed with a discussion of current areas of progress in subdisciplines including hybrid synthesis, functional surfaces, and functional interfaces.