521 research outputs found
An Anglo-Saxon execution cemetery at Walkington Wold, Yorkshire
This paper presents a re-evaluation of a cemetery excavated over
30 years ago at Walkington Wold in east Yorkshire. The cemetery is
characterized by careless burial on diverse alignments, and by the fact that
most of the skeletons did not have associated crania. The cemetery has been
variously described as being the result of an early post-Roman massacre, as
providing evidence for a ‘Celtic’ head cult or as an Anglo-Saxon execution
cemetery. In order to resolve the matter, radiocarbon dates were acquired and
a re-examination of the skeletal remains was undertaken. It was confirmed that
the cemetery was an Anglo-Saxon execution cemetery, the only known example
from northern England, and the site is set into its wider context in the paper
Reduced relative volume in motor and attention regions in developmental coordination disorder: a voxel-based morphometry study.
Background and Objectives: Developmental coordination disorder (DCD) is a prevalent childhood movement disorder, impacting the ability to perform movement skills at an age appropriate level. Although differences in grey matter (GM) volumes have been found in related developmental disorders, no such evidence has been linked with DCD to date. This cross-sectional study assessed structural brain differences in children with and without DCD. Methods: High-resolution structural images were acquired from 44 children aged 7.8–12 years, including 22 children with DCD (≤16th percentile on MABC-2; no ADHD/ASD), and 22 typically developing controls (≥20th percentile on MABC-2). Structural voxel-based morphology analysis was performed to determine group differences in focal GM volumes. Results: Children with DCD were found to have significant, large, right lateralised reductions in grey matter volume in the medial and middle frontal, and superior frontal gyri compared to controls. The addition of motor proficiency as a covariate explained the between-group GM volume differences, suggesting that GM volumes in motor regions are reflective of the level of motor proficiency. A positive correlation between motor proficiency and relative GM volume was also identified in the left posterior cingulate and precuneus. Conclusions: GM volume reductions in premotor frontal regions may underlie the motor difficulties characteristic of DCD. It is possible that intervention approaches targeting motor planning, attention, and executive functioning processes associated with the regions of reduced GM volume may result in functional improvements in children with DCD
Organotypic sinonasal airway culture systems are predictive of the mucociliary phenotype produced by bronchial airway epithelial cells
Published online: 10 November 2022Differentiated air-liquid interface models are the current standard to assess the mucociliary phenotype using clinically-derived samples in a controlled environment. However, obtaining basal progenitor airway epithelial cells (AEC) from the lungs is invasive and resource-intensive. Hence, we applied a tissue engineering approach to generate organotypic sinonasal AEC (nAEC) epithelia to determine whether they are predictive of bronchial AEC (bAEC) models. Basal progenitor AEC were isolated from healthy participants using a cytological brushing method and differentiated into epithelia on transwells until the mucociliary phenotype was observed. Tissue architecture was assessed using H&E and alcian blue/Verhoeff-Van Gieson staining, immunofluorescence (for cilia via acetylated α-tubulin labelling) and scanning electron microscopy. Differentiation and the formation of tight-junctions were monitored over the culture period (day 1-32) by quantifying trans-epithelial electrical resistance. End point (day 32) tight junction protein expression was assessed using Western blot analysis of ZO-1, Occludin-1 and Claudin-1. Reverse transcription qPCR-array was used to assess immunomodulatory and autophagy-specific transcript profiles. All outcome measures were assessed using R-statistical software. Mucociliary architecture was comparable for nAEC and bAEC-derived cultures, e.g. cell density P = 0.55, epithelial height P = 0.88 and cilia abundance P = 0.41. Trans-epithelial electrical resistance measures were distinct from day 1-14, converged over days 16-32, and were statistically similar over the entire culture period (global P 0.05). Transcript analysis for inflammatory markers demonstrated significant variation between nAEC and bAEC epithelial cultures, and favoured increased abundance in the nAEC model (e.g. TGFβ and IL-1β; P < 0.05). Conversely, the abundance of autophagy-related transcripts were comparable and the range of outcome measures for either model exhibited a considerably more confined uncertainty distribution than those observed for the inflammatory markers. Organotypic air-liquid interface models of nAEC are predictive of outcomes related to barrier function, mucociliary architecture and autophagy gene activity in corresponding bAEC models. However, inflammatory markers exhibited wide variation which may be explained by the sentinel immunological surveillance role of the sinonasal epithelium.Juliette Delhove, Moayed Alawami, Matthew Macowan, Susan E. Lester, Phan T. Nguyen, Hubertus P. A. Jersmann, Paul N. Reynolds and Eugene Rosciol
¿Legalización de la Marihuana recreativa en Colombia, una propuesta de ley viable?
Ensayo II Congreso Internacional COFACESEn el presente ensayo se hará referencia a la posibilidad de legalizar el comercio, la producción y el consumo del cannabis para uso recreativo en adultos en Colombia. Para lograr esto se debe hacer una modificación a la constitución política, y rebatir todos los argumentos que se tienen sobre el consumo de está, ya que es considerada una sustancia, adictiva, nociva y que representa un problema de salud pública.RESUMEN
INTRODUCCIÓN
DESARROLLO
CONCLUSIONES
BIBLIOGRAFÍAEspecializaciónEspecialista en Formulación y Evaluación Social y Económica de Proyecto
Continuation-Passing C: compiling threads to events through continuations
In this paper, we introduce Continuation Passing C (CPC), a programming
language for concurrent systems in which native and cooperative threads are
unified and presented to the programmer as a single abstraction. The CPC
compiler uses a compilation technique, based on the CPS transform, that yields
efficient code and an extremely lightweight representation for contexts. We
provide a proof of the correctness of our compilation scheme. We show in
particular that lambda-lifting, a common compilation technique for functional
languages, is also correct in an imperative language like C, under some
conditions enforced by the CPC compiler. The current CPC compiler is mature
enough to write substantial programs such as Hekate, a highly concurrent
BitTorrent seeder. Our benchmark results show that CPC is as efficient, while
using significantly less space, as the most efficient thread libraries
available.Comment: Higher-Order and Symbolic Computation (2012). arXiv admin note:
substantial text overlap with arXiv:1202.324
COVID-19 and use of non-traditional masks: how do various materials compare in reducing the risk of infection for mask wearers?
Abstract not available
An overview of jets and outflows in stellar mass black holes
In this book chapter, we will briefly review the current empirical
understanding of the relation between accretion state and and outflows in
accreting stellar mass black holes. The focus will be on the empirical
connections between X-ray states and relativistic (`radio') jets, although we
are now also able to draw accretion disc winds into the picture in a systematic
way. We will furthermore consider the latest attempts to measure/order jet
power, and to compare it to other (potentially) measurable quantities, most
importantly black hole spin.Comment: Accepted for publication in Space Science Reviews. Also to appear in
the Space Sciences Series of ISSI - The Physics of Accretion on to Black
Holes (Springer Publisher
The balance of power: accretion and feedback in stellar mass black holes
In this review we discuss the population of stellar-mass black holes in our
galaxy and beyond, which are the extreme endpoints of massive star evolution.
In particular we focus on how we can attempt to balance the available accretion
energy with feedback to the environment via radiation, jets and winds,
considering also possible contributions to the energy balance from black hole
spin and advection. We review quantitatively the methods which are used to
estimate these quantities, regardless of the details of the astrophysics close
to the black hole. Once these methods have been outlined, we work through an
outburst of a black hole X-ray binary system, estimating the flow of mass and
energy through the different accretion rates and states. While we focus on
feedback from stellar mass black holes in X-ray binary systems, we also
consider the applicability of what we have learned to supermassive black holes
in active galactic nuclei. As an important control sample we also review the
coupling between accretion and feedback in neutron stars, and show that it is
very similar to that observed in black holes, which strongly constrains how
much of the astrophysics of feedback can be unique to black holes.Comment: To be published in Haardt et al. Astrophysical Black Holes. Lecture
Notes in Physics. Springer 201
Pulsar-wind nebulae and magnetar outflows: observations at radio, X-ray, and gamma-ray wavelengths
We review observations of several classes of neutron-star-powered outflows:
pulsar-wind nebulae (PWNe) inside shell supernova remnants (SNRs), PWNe
interacting directly with interstellar medium (ISM), and magnetar-powered
outflows. We describe radio, X-ray, and gamma-ray observations of PWNe,
focusing first on integrated spectral-energy distributions (SEDs) and global
spectral properties. High-resolution X-ray imaging of PWNe shows a bewildering
array of morphologies, with jets, trails, and other structures. Several of the
23 so far identified magnetars show evidence for continuous or sporadic
emission of material, sometimes associated with giant flares, and a few
possible "magnetar-wind nebulae" have been recently identified.Comment: 61 pages, 44 figures (reduced in quality for size reasons). Published
in Space Science Reviews, "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray
Bursts and Blazars: Physics of Extreme Energy Release
Many Young Children with Autism Who Use Psychotropic Medication Do Not Receive Behavior Therapy: A Multisite Case-Control Study
Objectives: To explore how many pre-school aged children with autism spectrum disorder (ASD) used psychotropic medication, child and geographic factors associated with psychotropic medication use, and how many children who used psychotropic medication did or did not ever receive behavior therapy. Study design: Children 2-5 years of age were enrolled from 2012 to 2016 in a multisite case-control study designed to investigate the development and risk factors of ASD. Children with a positive ASD screen or ASD diagnosis upon enrollment were asked to complete a comprehensive evaluation to determine ASD status and developmental level. Caregivers completed a Services and Treatments Questionnaire and multiple self-administered questionnaires to determine child use of psychotropic medication, ever receipt of behavior therapy, and presence of co-occurring symptoms. Results: There were 763 children who were classified as ASD and had data collected on the Services and Treatments Questionnaire. Of those, 62 (8.1%) used psychotropic medication to treat behavioral symptoms and 28 (3.7%) were ≤3 years of age when medication was first started. Attention problems (aOR, 7.65; 95% CI, 3.41-16.1; P < .001) and study site (aOR, 2.62; 95% CI, 1.04-6.56; P = .04) were significantly associated with psychotropic medication use after controlling for maternal race/ethnicity. More than one-half (59.7%) of those who used psychotropic medication did not ever receive behavior therapy. Conclusions: Many preschool-aged children with ASD who use psychotropic medication do not receive behavior therapy. Pediatricians are an important resource for children and families and can help facilitate behavioral treatment for children with ASD and other disorders
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