9,960 research outputs found
"One-Stop Shopping" for Ocean Remote-Sensing and Model Data
OurOcean Portal 2.0 (http:// ourocean.jpl.nasa.gov) is a software system designed to enable users to easily gain access to ocean observation data, both remote-sensing and in-situ, configure and run an Ocean Model with observation data assimilated on a remote computer, and visualize both the observation data and the model outputs. At present, the observation data and models focus on the California coastal regions and Prince William Sound in Alaska. This system can be used to perform both real-time and retrospective analyses of remote-sensing data and model outputs. OurOcean Portal 2.0 incorporates state-of-the-art information technologies (IT) such as MySQL database, Java Web Server (Apache/Tomcat), Live Access Server (LAS), interactive graphics with Java Applet at the Client site and MatLab/GMT at the server site, and distributed computing. OurOcean currently serves over 20 real-time or historical ocean data products. The data are served in pre-generated plots or their native data format. For some of the datasets, users can choose different plotting parameters and produce customized graphics. OurOcean also serves 3D Ocean Model outputs generated by ROMS (Regional Ocean Model System) using LAS. The Live Access Server (LAS) software, developed by the Pacific Marine Environmental Laboratory (PMEL) of the National Oceanic and Atmospheric Administration (NOAA), is a configurable Web-server program designed to provide flexible access to geo-referenced scientific data. The model output can be views as plots in horizontal slices, depth profiles or time sequences, or can be downloaded as raw data in different data formats, such as NetCDF, ASCII, Binary, etc. The interactive visualization is provided by graphic software, Ferret, also developed by PMEL. In addition, OurOcean allows users with minimal computing resources to configure and run an Ocean Model with data assimilation on a remote computer. Users may select the forcing input, the data to be assimilated, the simulation period, and the output variables and submit the model to run on a backend parallel computer. When the run is complete, the output will be added to the LAS server fo
DCGL: an R package for identifying differentially coexpressed genes and links from gene expression microarray data
Summary: Gene coexpression analysis was developed to explore gene interconnection at the expression level from a systems perspective, and differential coexpression analysis (DCEA), which examines the change in gene expression correlation between two conditions, was accordingly designed as a complementary technique to traditional differential expression analysis (DEA). Since there is a shortage of DCEA tools, we implemented in an R package ‘DCGL’ five DCEA methods for identification of differentially coexpressed genes and differentially coexpressed links, including three currently popular methods and two novel algorithms described in a companion paper. DCGL can serve as an easy-to-use tool to facilitate differential coexpression analyses
Subtle features of delamination in cross-ply laminates due to low speed impact
In cross-ply laminates, the shape of delamination areas, which form due to low velocity impact, have two subtle features, which have been observed consistently in numerous experiments. Those are the pointed delamination tips and the intact zone between the lobes of delamination. However, there have not been any account available in the literature how they can be consistently captured through numerical modelling, and hence these features in published modelling results were often absent. It is the objective of this paper to identify the underlying modelling considerations so that these features can be captured with confidence. A key and unique reason has been identified in each case. Namely, inclusion of intra-laminar damage allows to reproduce the pointed delamination tips, while the gap between the lobes of delamination can be captured by models with sufficiently refined mesh, where friction between the laminas is taken into account. The capability of capturing these subtle features helps to raise the level of fidelity on the simulation of delamination due to impact
Violating Electrodynamics and Chern-Simons Modified Gravity
The electrodynamics with a Chern-Simons term
violates Lorentz and symmetries
with a non-vanishing . For a fixed vector , in this paper we
point out that the energy-momentum tensor of this theory coupled to the gravity
minimally is symmetric but not divergence free, which consequently makes the
gravitational field equation inconsistent. To preserve the consistency, we
introduce a Chern-Simons term in the gravity sector with the coefficient
determined by the Lorentz and violating term in the electromagnetic
field. Further we study the phenomenologies of the model on the cosmic
microwave background radiation and the relic gravitational waves.Comment: 11 pages, 1 figure, the version to appear in Physics Letters
Central gas entropy excess as a direct evidence for AGN feedback in galaxy groups and clusters
By analyzing Chandra X-ray data of a sample of 21 galaxy groups and 19 galaxy
clusters, we find that in 31 sample systems there exists a significant central
( kpc) gas entropy excess (), which
corresponds to keV per gas particle, beyond the power-law
model that best fits the radial entropy profile of outer regions. We also find
a distinct correlation between the central entropy excess and
-band luminosity of the central dominating galaxies (CDGs), which is
scaled as , where is tightly
associated with the mass of the supermassive black hole hosted in the CDG. In
fact, if an effective mass-to-energy conversion-efficiency of 0.02 is assumed
for the accretion process, the cumulative AGN feedback yields an extra heating of keV per particle, which is sufficient to explain the central entropy
excess. In most cases the AGN contribution can compensate the radiative loss of
the X-ray gas within the cooling radius ( keV per particle),
and apparently exceeds the energy required to deviate the scaling relations
from the self-similar predictions ( keV per particle). In
contrast to the AGN feedback, the extra heating provided by supernova
explosions accounts for keV per particle in groups and is
almost negligible in clusters. Therefore, the observed correlation between
and can be considered as a direct evidence for AGN
feedback in galaxy groups and clusters.Comment: 14 pages, 3 figures, accepted by RA
Recommended from our members
Profiles of SUMO and ubiquitin conjugation in an Alzheimer's disease model
► Global levels of ubiquitinated proteins increased in the hippocampus of Tg2576 mice. ► No global changes in either SUMO-1 or SUMO-2/3 conjugation in any brain regions analysed. ► SUMO conjugating and deconjugating enzymes, UBC9 and SENP-1, unaltered in Tg2576 mice. ► Total levels of AMPA and kainate receptors were also unaffected in Tg2576 mice. ► Posttranslational modification by ubiquitin may play a role in Alzheimer's disease
Donut-Shaped Li4Ti5O12 Structures as a High Performance Anode Material for Lithium Ion Batteries
Lithium titanate (LTO) spinel 3D porous sub-micrometer donuts synthesized by combined sol-gel and electrospraying reveal a wall thickness of 200–250 nm with grain sizes in the range of 60–100 nm. Electrochemical testing of sub-micrometer donuts in half-cell mode exhibited a reversible specific capacity of 141 mAh/g even after 200 cycles of charging and discharging at 1C rate. The LTO structures with nanograins effectively reduce the Li ion diffusion path length, providing easy charge and discharge with good cyclability
Early Growth Response Factor-1 Is Associated With Intraluminal Thrombus Formation in Human Abdominal Aortic Aneurysm
ObjectivesThe goal of this study was to investigate the expression of early growth response-1 (Egr-1), a vascular pathogenic transcription factor, and its potential relationship with tissue factor (TF), a key player during the thrombus formation in the abdominal aortic aneurysm (AAA) wall.BackgroundAlthough intraluminal thrombus is a common finding in human AAA, the molecular mechanism of the thrombus formation has not been studied.MethodsDuring the elective AAA repair, specimens were taken from the thrombus-covered and thrombus-free portions of the aneurysmal wall in each of 16 patients with AAA and analyzed to assess the differential expression of Egr-1 and TF. The proinflammatory and prothrombogenic activities of Egr-1 in vasculature were evaluated in vitro and in vivo by overexpressing it using adenovirus.ResultsThe expression of both Egr-1 and TF was significantly increased in the thrombus-covered wall compared with the thrombus-free wall, in which their up-regulation in the thrombus-covered wall was strongly correlated with each other (p < 0.005, r = 0.717). Adenoviral overexpression of Egr-1 in human vascular smooth muscle and endothelial cells was found to up-regulate the expression of TF and inflammation-related genes. Moreover, Egr-1 overexpression in endothelial cells increased their adhesiveness to monocytes and also substantially promoted the intravascular thrombus formation in vivo, as shown in the inferior vena cava ligation experiment of the rat.ConclusionsThe present study demonstrates the differential up-regulation of Egr-1 in the thrombus-covered wall of human AAA and also suggests its possible contribution to the thrombogenic and inflammatory pathogenesis in human AAA
- …