114 research outputs found
The ATLAS Detector: Status and Results from Cosmic Rays
The ATLAS detector at the Large Hadron Collider, CERN has been under
construction for more than a decade. It is now largely complete and functional.
This paper will describe the state of the major subsystems of ATLAS. Results
from the brief single beam running period in 2008 will be shown. In addition,
results from a long period of cosmic ray running will be shown. These results
show that ATLAS is prepared to make major new physics discoveries as soon as we
get colliding beams in late 2009.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July
2009, eConf C09072
Hydrogen-bonding interactions in T-2 toxin studies using solution and solid-state NMR
Open accessThe structure of T-2 toxin in the solid-state is limited to X-ray crystallographic
studies, which lack sufficient resolution to provide direct evidence for hydrogen-bonding
interactions. Furthermore, its solution-structure, despite extensive Nuclear Magnetic
Resonance (NMR) studies, has provided little insight into its hydrogen-bonding behavior,
thus far. Hydrogen-bonding interactions are often an important part of biological activity.
In order to study these interactions, the structure of T-2 toxin was compared in both the
solution- and solid-state using NMR Spectroscopy. It was determined that the solution- and
solid-state structure differ dramatically, as indicated by differences in their carbon
chemical shifts, these observations are further supported by solution proton spectral
parameters and exchange behavior. The slow chemical exchange process and
cross-relaxation dynamics with water observed between the hydroxyl hydrogen on C-3 and
water supports the existence of a preferential hydrogen bonding interaction on the opposite
side of the molecule from the epoxide ring, which is known to be essential for
trichothecene toxicity. This result implies that these hydrogen-bonding interactions could
play an important role in the biological function of T-2 toxin and posits towards a possible interaction for the trichothecene class of toxins and the ribosome. These findings clearly
illustrate the importance of utilizing solid-state NMR for the study of biological
compounds, and suggest that a more detailed study of this whole class of toxins, namely
trichothecenes, should be pursued using this methodology.Ye
1973: Abilene Christian College Bible Lectures - Full Text
JESUS
Being the Abilene Christian College Annual Bible Lectures 1973
Published by
ABILENE CHRISTIAN COLLEGE BOOK STORE
ACC Station Abilene, Texas 7960
Motivational Factors Influencing Sport Spectator Involvement At NCAA Division II Basketball Games
Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector
The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry
Alterations of Blood Brain Barrier Function in Hyperammonemia: An Overview
Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute—(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of different molecules across the blood brain barrier (BBB). A brief description is provided of the tight junctions, which couple adjacent cerebral capillary endothelial cells to each other to form the barrier. Ammonia modulates the transcellular passage of low-to medium-size molecules, by affecting their carriers located at the BBB. Ammonia induces interrelated aberrations of the transport of the large neutral amino acids and aromatic amino acids (AAA), whose influx is augmented by exchange with glutamine produced in the course of ammonia detoxification, and maybe also modulated by the extracellularly acting gamma-glutamyl moiety transferring enzyme, gamma-glutamyl-transpeptidase. Impaired AAA transport affects neurotransmission by altering intracerebral synthesis of catecholamines (serotonin and dopamine), and producing “false neurotransmitters” (octopamine and phenylethylamine). Ammonia also modulates BBB transport of the cationic amino acids: the nitric oxide precursor, arginine, and ornithine, which is an ammonia trap, and affects the transport of energy metabolites glucose and creatine. Moreover, ammonia acting either directly or in synergy with liver injury-derived inflammatory cytokines also evokes subtle increases of the transcellular passage of molecules of different size (BBB “leakage”), which appears to be responsible for the vasogenic component of cerebral edema associated with ALF
Fluorogenic Dendrons with Multiple Donor Chromophores as Bright Genetically Targeted and Activated Probes
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