11,993 research outputs found
Planck Fluctuations, Measurement Uncertainties and the Holographic Principle
Starting from a critical analysis of recently reported surprisingly large
uncertainties in length and position measurements deduced within the framework
of quantum gravity, we embark on an investigation both of the correlation
structure of Planck scale fluctuations and the role the holographic hypothesis
is possibly playing in this context. While we prove the logical independence of
the fluctuation results and the holographic hypothesis (in contrast to some
recent statements in that direction) we show that by combining these two topics
one can draw quite strong and interesting conclusions about the fluctuation
structure and the microscopic dynamics on the Planck scale. We further argue
that these findings point to a possibly new and generalized form of quantum
statistical mechanics of strongly (anti)correlated systems of degrees of
freedom in this fundamental regime.Comment: 19 pages, Latex, no figures, some new references, to appear
ModPhysLett
Survival of the NASA Mars Odyssey isolate Acinetobacter radioresistens 50v1 on different spaceflight relevant antimicrobial surfaces
Since many years, human mankind travels to space. One of our
mayor interests is the health of astronauts and the protection of the
spacecraft. Apart from external influences, the microbial burden
inside of the International Space Station (ISS) may be dangerous
and must be limited to a minimum. To ensure the status and the
protection of the crew as well as the spacecraft itself, it is
necessary to determine the survival of microorganisms on
different surfaces. Microorganisms are constantly changing their
strategy of survival, primarily induced by extreme environmental
conditions, such as space conditions, compared to their terrestrial
habitats. However, the increased levels in resistance and
robustness possibly play a sensitive role in evolving new virulence
factors in the space environment.
One of the bacteria on the NASA Mars Odyssey spacecraft, which
have been isolated, is the Gram-negative, non-motile bacterium
Acinetobacter radioresistens. Apart from Deinococcus
radiodurans, A. radioresistens shows similar levels in radiation
and oxidative stress tolerance (McCoy et al., 2012). In our work, we used the strain 50v1, isolated from the surface of the Mars
Odyssey spacecraft as well as the type strain DSM6976, which
was isolated on Earth from cotton and soil samples. We
investigated the resistance regarding in their desiccation tolerance
on metallic surfaces including materials with different
antimicrobial properties. For those experiments we exposed and
desiccated both strains on the different surfaces (such as copperand
silver-containing materials) and determined the survival over
different time points. First results show a high resistance of the
spacecraft isolated strain compared to the type strain. These
results give implications about the higher survivability of
environmental microorganisms and highlight the essence of
bioburden reduction and improve sterilization
approaches/techniques for upcoming space exploration missions
towards the search for life outside Earth
The tectonic and sedimentary structures of the Tyrrhenian rifted basin from multichannel seismic images
Deep Eyes: Binocular Depth-from-Focus on Focal Stack Pairs
Human visual system relies on both binocular stereo cues and monocular
focusness cues to gain effective 3D perception. In computer vision, the two
problems are traditionally solved in separate tracks. In this paper, we present
a unified learning-based technique that simultaneously uses both types of cues
for depth inference. Specifically, we use a pair of focal stacks as input to
emulate human perception. We first construct a comprehensive focal stack
training dataset synthesized by depth-guided light field rendering. We then
construct three individual networks: a Focus-Net to extract depth from a single
focal stack, a EDoF-Net to obtain the extended depth of field (EDoF) image from
the focal stack, and a Stereo-Net to conduct stereo matching. We show how to
integrate them into a unified BDfF-Net to obtain high-quality depth maps.
Comprehensive experiments show that our approach outperforms the
state-of-the-art in both accuracy and speed and effectively emulates human
vision systems
Short Courses: Flexible Learning Opportunities in Informatics
In today’s fast-paced, data-driven world, researchers need to have a good foundation in informatics to store, organize, process, and analyze growing amounts of data. However, not all degree programs offer such training. Obtaining training in informatics on your own can be a daunting task for both new and established researchers who have little informatics experience. Providing educational opportunities appropriate for various skill levels and that mesh with a full-time schedule can remove barriers and foster a collaborative, informatics-savvy community that is better equipped to push science forward.
To enhance informatics education in bioinformatics, VCUs Wright Center for Clinical and Translational Research of- fers a complementary series of seminars and workshops. These short course offerings introduce attendees to bioinformatics concepts and applications, and provide hands-on experience using online Bioinformatics databases. Bioinformatics 101 (B101) is an 8-week long series of 1-hour seminars focused on introducing topics in bioinformatics related to Next Generation Sequencing (NGS). Lectures are application focused and include overviews of NGS technology, practical bioinformatics pipelines, and examples of how the technology can influence downstream bioinformatics analyses. Bioinformatics 102 (B102) is a 5-day, 2 hours per day workshop developed in collaboration with VCU Libraries that provides attendees with hands-on experience accessing and using public data repositories. Sessions include a brief lecture followed by hands-on exercises. A Certificate of Completion is awarded upon meeting certain criteria for either the 101 or 102 courses.
Bioinformatics 101 has been offered 3 times with a combined total of 246 registrants, and Bioinformatics 102 has been offered twice with a total of 78 registrants (limited to 30 per session per day). From course surveys, 82% (n=108) and 95% (n=47) of respondents gave B101 and B102 a positive rating, respectively. In addition, 89% of B101 respondents indicated their knowledge was improved, with 100% of B102 respondents indicating the same. A total of 84 and 33 certificates have been awarded for B101 and B102, respectively.
The Bioinformatics 101 and 102 courses have become highly anticipated across the university, and have gained the external attention of surrounding businesses and colleges. Registrants have diverse backgrounds including biological, clinical, computational, administrative, librarian, business, and others with a total of 77 departments across VCU and VCU Health represented. Due to this interest, Bioinformatics 101 began offering live online attendance to accommodate those who were unable to travel across campus, or who are attending from outside VCU. This past year, 50% of attendance was online indicating a growing need for flexible education opportunities in informatics.
Increasing researcher knowledge of Bioinformatics along with awareness of university resources for informatics support fosters an informatics-savvy research community that is empowered to take advantage of existing and new data sources in the pursuit of new insights and scientific discoveries for the betterment of human health. Future work will include the development of a more comprehensive educational framework by creating new and flexible learning opportunities that will make informatics education easy and convenient for our dedicated researchers
Half-lives of rp-process waiting point nuclei
We give results of microscopic calculations for the half-lives of various
proton-rich nuclei in the mass region A=60-90, which are involved in the
astrophysical rp-process, and which are needed as input parameters of numerical
simulations in Nuclear Astrophysics. The microscopic formalism consists of a
deformed QRPA approach that involves a selfconsistent quasiparticle deformed
Skyrme Hartree-Fock basis and residual spin-isospin separable forces in both
the particle-hole and particle-particle channels. The strength of the
particle-hole residual interaction is chosen to be consistent with the Skyrme
effective force and mean field basis, while that of the particle-particle is
globally fixed to 0.07 MeV after a judicious choice from comparison to
experimental half-lives. We study and discuss the sensitivity of the half-lives
to deformation and residual interactions.Comment: 8 pages, 4 figures, to be published in Eur. Phys. J.
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