1,936 research outputs found
Developing a Proactive Framework for E-Discovery Compliance
The purpose of this document is to provide Information Systems Management an awareness of a compliance risk associated with the management of electronic data. The changes to the Federal Rules of Civil Procedure in 2006 make electronic data discoverable as evidence for civil court cases introducing the need for proactive management of end user data beyond the data that a particular form of legislation may require. Leveraging existing forensic data collection processes and raising the awareness of the problem and risk to the organization will provide a level of assurance for compliance should the data be requested in a civil trial. This project analyzed the current state that existed for businesses and organizations, the actual risk and precedence that has been set, and determines the current state of awareness and readiness that businesses have for this problem. The project then offers a solution to this problem that will aid in reducing the risk and hardship an organization could face when electronic data is requested. Finally, this project presents the results of actual testing of the proposed solution in a real world business enterprise
Homotaurine, a safe blood-brain barrier permeable GABAA-R-specific agonist, ameliorates disease in mouse models of multiple sclerosis.
There is a need for treatments that can safely promote regulatory lymphocyte responses. T cells express GABA receptors (GABAA-Rs) and GABA administration can inhibit Th1-mediated processes such as type 1 diabetes and rheumatoid arthritis in mouse models. Whether GABAA-R agonists can also inhibit Th17-driven processes such as experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS), is an open question. GABA does not pass through the blood-brain barrier (BBB) making it ill-suited to inhibit the spreading of autoreactivity within the CNS. Homotaurine is a BBB-permeable amino acid that antagonizes amyloid fibril formation and was found to be safe but ineffective in long-term Alzheimer's disease clinical trials. Homotaurine also acts as GABAA-R agonist with better pharmacokinetics than that of GABA. Working with both monophasic and relapsing-remitting mouse models of EAE, we show that oral administration of homotaurine can (1) enhance CD8+CD122+PD-1+ and CD4+Foxp3+ Treg, but not Breg, responses, (2) inhibit autoreactive Th17 and Th1 responses, and (3) effectively ameliorate ongoing disease. These observations demonstrate the potential of BBB-permeable GABAA-R agonists as a new class of treatment to enhance CD8+ and CD4+ Treg responses and limit Th17 and Th1-medaited inflammation in the CNS
New attempts to understand nanodiamond stardust
We report on a concerted effort aimed at understanding the origin and history
of the pre-solar nanodiamonds in meteorites including the astrophysical sources
of the observed isotopic abundance signatures. This includes measurement of
light elements by secondary ion mass spectrometry (SIMS), analysis of
additional heavy trace elements by accelerator mass spectrometry (AMS) and
dynamic calculations of r-process nucleosynthesis with updated nuclear
properties. Results obtained indicate: a) there is no evidence for the former
presence of now extinct 26Al and 44Ti in our diamond samples other than what
can be attributed to silicon carbide and other "impurities"; this does not
offer support for a supernova (SN) origin but neither does it negate it; b)
analysis by AMS of platinum in "bulk diamond" yields an overabundance of r-only
198Pt that at face value seems more consistent with the neutron burst than with
the separation model for the origin of heavy trace elements in the diamonds,
although this conclusion is not firm given analytical uncertainties; c) if the
Xe-H pattern was established by an unadulterated r-process, it must have been a
strong variant of the main r-process, which possibly could also account for the
new observations in platinum.Comment: Workshop on Astronomy with Radioactvities VII; Publications of the
Astronomical Society of Australia, accepte
AMS measurements of cosmogenic and supernova-ejected radionuclides in deep-sea sediment cores
Samples of two deep-sea sediment cores from the Indian Ocean are analyzed
with accelerator mass spectrometry (AMS) to search for traces of recent
supernova activity around 2 Myr ago. Here, long-lived radionuclides, which are
synthesized in massive stars and ejected in supernova explosions, namely 26Al,
53Mn and 60Fe, are extracted from the sediment samples. The cosmogenic isotope
10Be, which is mainly produced in the Earths atmosphere, is analyzed for dating
purposes of the marine sediment cores. The first AMS measurement results for
10Be and 26Al are presented, which represent for the first time a detailed
study in the time period of 1.7-3.1 Myr with high time resolution. Our first
results do not support a significant extraterrestrial signal of 26Al above
terrestrial background. However, there is evidence that, like 10Be, 26Al might
be a valuable isotope for dating of deep-sea sediment cores for the past few
million years.Comment: 5 pages, 2 figures, Proceedings of the Heavy Ion Accelerator
Symposium on Fundamental and Applied Science, 2013, will be published by the
EPJ Web of conference
Settling the half-life of â¶â°Fe: fundamental for a versatile astrophysical chronometer
In order to resolve a recent discrepancy in the half-life of â¶â°Fe, we performed an independent measurement with a new method that determines the â¶â°Fe content of a material relative to Fe55 (t1/2=2.744yr) with accelerator mass spectrometry. Our result of (2.50±0.12)Ă10â¶yr clearly favors the recently reported value (2.62±0.04)Ă10â¶yr, and rules out the older result of (1.49±0.27)Ă10â¶yr. The present weighted mean half-life value of (2.60±0.05)Ă10â¶yr substantially improves the reliability as an important chronometer for astrophysical applications in the million-year time range. This includes its use as a sensitive probe for studying recent chemical evolution of our Galaxy, the formation of the early Solar System, nucleosynthesis processes in massive stars, and as an indicator of a recent nearby supernova.Part of this work was funded by the Austrian Science
Fund (FWF) Projects No. AP20434 and AI00428 (FWF
and CoDustMas, Eurogenesis via ESF)
The Search for Supernova-produced Radionuclides in Terrestrial Deep-sea Archives
An enhanced concentration of 60Fe was found in a deep ocean's crust in 2004
in a layer corresponding to an age of ~2 Myr. The confirmation of this signal
in terrestrial archives as supernova-induced and detection of other
supernova-produced radionuclides is of great interest. We have identified two
suitable marine sediment cores from the South Australian Basin and estimated
the intensity of a possible signal of the supernova-produced radionuclides
26Al, 53Mn, 60Fe and the pure r-process element 244Pu in these cores. A finding
of these radionuclides in a sediment core might allow to improve the time
resolution of the signal and thus to link the signal to a supernova event in
the solar vicinity ~2 Myr ago. Furthermore, it gives an insight on
nucleosynthesis scenarios in massive stars, the condensation into dust grains
and transport mechanisms from the supernova shell into the solar system
Ion Sources for MedAustron
The MedAustron Ion therapy center will be constructed in Wiener Neustadt (Austria) in the vicinity of Vienna. Its accelerator complex consists of four ion sources, a linear accelerator, a synchrotron and a beam delivery system to the three medical treatment rooms and to the research irradiation room. The ion sources shall deliver beams of H31+, C4+ and light ions with utmost reliability and stability. This paper describes the features of the ion sources presently planned for the MedAustron facility; such as ion source main parameters, gas injection, temperature control and cooling systems. A dedicated beam diagnostics technique is proposed in order to characterize ECR ions beams; in the first drift region after the ion source, a fraction of the mixed beam is selected via moveable aperture. With standard beam diagnostics, we then aim to produce position-dependant observables such as ion-current density, beam energy distribution and emittance for each charge states to be compared to simulations of ECR e-heating, plasma simulation, beam formation and transport
From Gravitons to Gravity: Myths and Reality
There is a general belief, reinforced by statements in standard textbooks,
that: (i) one can obtain the full non-linear Einstein's theory of gravity by
coupling a massless, spin-2 field self-consistently to the total
energy momentum tensor, including its own; (ii) this procedure is unique and
leads to Einstein-Hilbert action and (iii) it only uses standard concepts in
Lorentz invariant field theory and does not involve any geometrical
assumptions. After providing several reasons why such beliefs are suspect --
and critically re-examining several previous attempts -- we provide a detailed
analysis aimed at clarifying the situation. First, we prove that it is
\textit{impossible} to obtain the Einstein-Hilbert (EH) action, starting from
the standard action for gravitons in linear theory and iterating repeatedly.
Second, we use the Taylor series expansion of the action for Einstein's theory,
to identify the tensor , to which the graviton field
couples to the lowest order. We show that the second rank tensor
is {\it not} the conventional energy momentum tensor
of the graviton and provide an explanation for this feature. Third, we
construct the full nonlinear Einstein's theory with the source being spin-0
field, spin-1 field or relativistic particles by explicitly coupling the spin-2
field to this second rank tensor order by order and summing
up the infinite series. Finally, we construct the theory obtained by self
consistently coupling to the conventional energy momentum tensor
order by order and show that this does {\it not} lead to Einstein's
theory. (condensed).Comment: revtex; 19 pages; no figure
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