313 research outputs found
Synthesis of Bounded Choice-Free Petri Nets
This paper describes a synthesis algorithm tailored to the construction of choice-free Petri nets from finite persistent transition systems. With this goal in mind, a minimised set of simplified systems of linear inequalities is distilled from a general region-theoretic approach, leading to algorithmic improvements as well as to a partial characterisation of the class of persistent transition systems that have a choice-free Petri net realisation
Radio loud AGN and the L_X - \sigma relation of galaxy groups and clusters
We use the ROSAT All-Sky Survey to study the X-ray properties of a sample of
625 groups and clusters of galaxies selected from the Sloan Digital Sky Survey.
We stack clusters with similar velocity dispersions and investigate whether
their average X-ray luminosities and surface brightness profiles vary with the
radio activity level of their central galaxies. We find that at a given value
of , clusters with a central radio AGN have more concentrated X-ray
surface brightness profiles, larger central galaxy masses, and higher X-ray
luminosities than clusters with radio-quiet central galaxies. The enhancement
in X-ray luminosity is more than a factor of two, is detected with better than
6 significance, and cannot be explained by X-ray emission from the
radio AGN itself. This difference is largely due to a subpopulation of
radio-quiet, high velocity dispersion clusters with low mass central galaxies.
These clusters are underluminous at X-ray wavelengths when compared to
otherwise similar clusters where the central galaxy is radio-loud, more
massive, or both.Comment: Section 5.2 is updated, more discussion on the dependence of L_X -
\sigma relation on the stellar mass of BCG
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Concentrations of remdesivir and GS-441524 in human milk from lactating individuals diagnosed with COVID-19
ImpactFindings from this study provide further reassuring evidence that infant exposure through human milk received from lactating individuals who require treatment with remdesivir is negligible
An X-ray review of MS1054-0321: hot or not?
XMM-Newton observations are presented for the z=0.83 cluster of galaxies
MS1054-0321, the highest redshift cluster in the Einstein Extended Medium
Sensitivity Survey (EMSS). The temperature inferred by the XMM-Newton data,
T=7.2 (+0.7, -0.6) keV, is much lower than the temperature previously reported
from ASCA data, T=12.3 (+3.1, -2.2) keV (Donahue et al. 1998), and a little
lower than the Chandra temperature, T=10.4(+1.7, -1.5) keV, determined by
Jeltema et al. 2001. The discrepancy between the newly derived temperature and
the previously derived temperatures is discussed in detail. If one allows the
column density to be a free parameter, then the best fit temperature becomes
T=8.6 (+1.2, -1.1) keV, and the best fit column density becomes N_(H)=1.33
(+0.15 -0.14) x 10^20 atoms/cm^2. The iron line is well detected in the
XMM-Newton spectrum with a value for the abundance of Z=0.33 (+0.19 -0.18)
Zsol, in very good agreement with previous determinations. The derived XMM
X-ray luminosity for the overall cluster in the 2-10 keV energy band is
L_X=(3.81 +/- 0.19) x 10^44 h^-2 erg s^-1 while the bolometric luminosity is
L_BOL=(8.05+/-0.40) x 10^44 h^-2 erg s^-1. The XMM-Newton data confirm the
substructure in the cluster X-ray morphology already seen by ROSAT and in much
more detail by Chandra. The central weak lensing clump is coincident with the
main cluster component and has a temperature T=8.1 (+1.3, -1.2) keV. The
western weak lensing clump coincides with the western X-ray component which is
much cooler with a temperature T=5.6 (+0.8, -0.6)$ keV. Given the newly
determined temperature, MS1054-0321 is no longer amongst the hottest clusters
known.Comment: To appear in the A&A main Journal, 13 pages including 3 postscript
figures and 4 tables. Figs. 1, 4, 5 and 7 are too large and are not given
here. The whole paper as pdf file is posted at
http://www.ira.cnr.it/~gioia/PUB/publications.htm
A user's guide to the local arithmetic of hyperelliptic curves
A new approach has been recently developed to study the arithmetic of
hyperelliptic curves over local fields of odd residue characteristic
via combinatorial data associated to the roots of . Since its introduction,
numerous papers have used this machinery of "cluster pictures" to compute a
plethora of arithmetic invariants associated to these curves. The purpose of
this user's guide is to summarise and centralise all of these results in a
self-contained fashion, complemented by an abundance of examples.Comment: Minor changes. To appear in the Bulletin of the London Mathematical
Societ
Community level digital mental health interventions:A policy and practice brief
The prevalence of mental ill-health is increasing worldwide and brings adverse consequences at both the individual and societal level. Treatments and interventions for the symptoms that represent mental health conditions may target biological, behavioural and cognitive factors. Traditionally, treatments have included psychotropic medication, and/or psychological therapies which are delivered on a one to one or group basis. Both have a high economic cost, and efficacy varies. In addition, help seeking behaviour is impacted by stigma, symptom recognition & understanding, and a host of factors associated with the disorders themselves, such as avoidance behaviour. The delivery of face-to-face interventions for those who are most marginalised and most at risk from mental ill-health, can also be impacted by barriers, such as knowledge of the services available and time, connectivity or travel constraints. The research presented here is co-produced with service providers, end users and academic experts across the disciplines of psychology, business, medicine, healthcare, interaction design and computer science. This briefing is based on the findings from our research programme on a community level digital mental health intervention.<br/
Interleukin-1β Produced in Response to Islet Autoantigen Presentation Differentiates T-Helper 17 Cells at the Expense of Regulatory T-Cells: Implications for the Timing of Tolerizing Immunotherapy
OBJECTIVE-The effectiveness of tolerizing immunotherapeutic strategies, such as anti-CD40L or dendritic cells (DCs), is greater when administered to young nonobese diabetic (NOD) mice than at peak insulitis. RelB(lo) DCs, generated in the presence of an nuclear factor-kappa B inhibitor, induce T-regulatory (Treg) cells and suppress inflammation in a model of rheumatoid arthritis. Interleukin (IL)-1 beta is overexpressed in humans and mice at risk of type 1 diabetes, dysregulates Treg cells, and accelerates diabetes in NOD mice. We investigated the relationship between IL-1 beta production and the response to RelB(lo) DCs in the prediabetic period
Influence of structural variation on nuclear localization of DNA-binding polyamide-fluorophore conjugates
A pivotal step forward in chemical approaches to controlling gene expression is the development of sequence-specific DNA-binding molecules that can enter live cells and traffic to nuclei unaided. DNA-binding polyamides are a class of programmable, sequence-specific small molecules that have been shown to influence a wide variety of protein–DNA interactions. We have synthesized over 100 polyamide-fluorophore conjugates and assayed their nuclear uptake profiles in 13 mammalian cell lines. The compiled dataset, comprising 1300 entries, establishes a benchmark for the nuclear localization of polyamide-dye conjugates. Compounds in this series were chosen to provide systematic variation in several structural variables, including dye composition and placement, molecular weight, charge, ordering of the aromatic and aliphatic amino-acid building blocks and overall shape. Nuclear uptake does not appear to be correlated with polyamide molecular weight or with the number of imidazole residues, although the positions of imidazole residues affect nuclear access properties significantly. Generally negative determinants for nuclear access include the presence of a ß-Ala-tail residue and the lack of a cationic alkyl amine moiety, whereas the presence of an acetylated 2,4-diaminobutyric acid-turn is a positive factor for nuclear localization. We discuss implications of these data on the design of polyamide-dye conjugates for use in biological systems
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