721 research outputs found
Supersymmetric Randall-Sundrum Scenario
We present the supersymmetric version of the minimal Randall-Sundrum model
with two opposite tension branes.Comment: Latex, 9 pages. Published versio
A practical approach for quantitative estimates of voxelâbyâvoxel liver perfusion using DCE imaging and a compartmental model
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135027/1/mp9773.pd
Transcriptional Signatures of Tau and Amyloid Neuropathology
Alzheimer's disease (AD) is associated with the intracellular aggregation of hyperphosphorylated tau and the accumulation of β-amyloid in the neocortex. We use transgenic mice harboring human tau (rTg4510) and amyloid precursor protein (J20) mutations to investigate transcriptional changes associated with the progression of tau and amyloid pathology. rTg4510 mice are characterized by widespread transcriptional differences in the entorhinal cortex with changes paralleling neuropathological burden across multiple brain regions. Differentially expressed transcripts overlap with genes identified in genetic studies of familial and sporadic AD. Systems-level analyses identify discrete co-expression networks associated with the progressive accumulation of tau that are enriched for genes and pathways previously implicated in AD pathology and overlap with co-expression networks identified in human AD cortex. Our data provide further evidence for an immune-response component in the accumulation of tau and reveal molecular pathways associated with the progression of AD neuropathology.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.WT_/Wellcome Trust/United Kingdom
MR/M008924/1/MRC_/Medical Research Council/United Kingdompublished version, accepted version, submitted versio
Randomized trial of conventional transseptal needle versus radiofrequency energy needle puncture for left atrial access (the TRAVERSE-LA study).
BackgroundTransseptal puncture is a critical step in achieving left atrial (LA) access for a variety of cardiac procedures. Although the mechanical Brockenbrough needle has historically been used for this procedure, a needle employing radiofrequency (RF) energy has more recently been approved for clinical use. We sought to investigate the comparative effectiveness of an RF versus conventional needle for transseptal LA access.Methods and resultsIn this prospective, single-blinded, controlled trial, 72 patients were randomized in a 1:1 fashion to an RF versus conventional (BRK-1) transseptal needle. In an intention-to-treat analysis, the primary outcome was time required for transseptal LA access. Secondary outcomes included failure of the assigned needle, visible plastic dilator shavings from needle introduction, and any procedural complication. The median transseptal puncture time was 68% shorter using the RF needle compared with the conventional needle (2.3 minutes [interquartile range {IQR}, 1.7 to 3.8 minutes] versus 7.3 minutes [IQR, 2.7 to 14.1 minutes], P = 0.005). Failure to achieve transseptal LA access with the assigned needle was less common using the RF versus conventional needle (0/36 [0%] versus 10/36 [27.8%], P < 0.001). Plastic shavings were grossly visible after needle advancement through the dilator and sheath in 0 (0%) RF needle cases and 12 (33.3%) conventional needle cases (P < 0.001). There were no differences in procedural complications (1/36 [2.8%] versus 1/36 [2.8%]).ConclusionsUse of an RF needle resulted in shorter time to transseptal LA access, less failure in achieving transseptal LA access, and fewer visible plastic shavings
An overview of the CellML API and its implementation
<p>Abstract</p> <p>Background</p> <p>CellML is an XML based language for representing mathematical models, in a machine-independent form which is suitable for their exchange between different authors, and for archival in a model repository. Allowing for the exchange and archival of models in a computer readable form is a key strategic goal in bioinformatics, because of the associated improvements in scientific record accuracy, the faster iterative process of scientific development, and the ability to combine models into large integrative models.</p> <p>However, for CellML models to be useful, tools which can process them correctly are needed. Due to some of the more complex features present in CellML models, such as imports, developing code <it>ab initio </it>to correctly process models can be an onerous task. For this reason, there is a clear and pressing need for an application programming interface (API), and a good implementation of that API, upon which tools can base their support for CellML.</p> <p>Results</p> <p>We developed an API which allows the information in CellML models to be retrieved and/or modified. We also developed a series of optional extension APIs, for tasks such as simplifying the handling of connections between variables, dealing with physical units, validating models, and translating models into different procedural languages.</p> <p>We have also provided a Free/Open Source implementation of this application programming interface, optimised to achieve good performance.</p> <p>Conclusions</p> <p>Tools have been developed using the API which are mature enough for widespread use. The API has the potential to accelerate the development of additional tools capable of processing CellML, and ultimately lead to an increased level of sharing of mathematical model descriptions.</p
Atherosclerosis in Indigenous Tsimane: A Contemporary Perspective
The Horus and other research teams have found that atherosclerosis is not uncommon in ancient people through the study of their mummified remains (Murphy et al., 2003; Allam et al., 2009, 2011; Thompson et al., 2013, 2014). However, some have postulated that traditional hunter-gatherers are in some ways healthier than modern people and that they had very little atherosclerotic disease (OâKeefe et al., 2010). The aim of this study was to evaluate the burden of atherosclerosis in a population alive today but living a traditional lifestyle similar to that experienced by past populations. This led to the Tsimane Health and Life History Project Team (THLHP) (Gurven et al., 2017) and the Horus Study Team combining efforts to evaluate the prevalence and extent of coronary atherosclerosis in the Tsimane of Bolivia (Kaplan et al., 2017)
Chandra ACIS Survey of M33 (ChASeM33): A First Look
We present an overview of the Chandra ACIS Survey of M33 (ChASeM33): A Deep
Survey of the Nearest Face-on Spiral Galaxy. The 1.4 Ms survey covers the
galaxy out to R \approx 18\arcmin (\approx 4 kpc). These data provide the
most intensive, high spatial resolution assessment of the X-ray source
populations available for the confused inner regions of M33. Mosaic images of
the ChASeM33 observations show several hundred individual X-ray sources as well
as soft diffuse emission from the hot interstellar medium. Bright, extended
emission surrounds the nucleus and is also seen from the giant \hii regions NGC
604 and IC 131. Fainter extended emission and numerous individual sources
appear to trace the inner spiral structure. The initial source catalog, arising
from ~2/3 of the expected survey data, includes 394 sources significant
at the confidence level or greater, down to a limiting luminosity
(absorbed) of 1.6\ergs{35} (0.35 -- 8.0 keV). The hardness ratios of the
sources separate those with soft, thermal spectra such as supernova remnants
from those with hard, non-thermal spectra such as X-ray binaries and background
active galactic nuclei. Emission extended beyond the Chandra point spread
function is evident in 23 of the 394 sources. Cross-correlation of the ChASeM33
sources against previous catalogs of X-ray sources in M33 results in matches
for the vast majority of the brighter sources and shows 28 ChASeM33 sources
within 10\arcsec of supernova remnants identified by prior optical and radio
searches. This brings the total number of such associations to 31 out of 100
known supernova remnants in M33.Comment: accepted for publication ApJS, full resolution images and complete
tables available at http://hea-www.harvard.edu/vlp_m33_public
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