639 research outputs found
3D modelling of geological and anthropogenic deposits at the World Heritage Site of Bryggen in Bergen, Norway
The landscape of many historic cities and the character of their shallow subsurface environments are
defined by a legacy of interaction between anthropogenic and geological processes. Anthropogenic
deposits and excavations result from processes ranging from archaeological activities to modern urban
development. Hence, in heritage cities, any geological investigation should acknowledge the role of past
and ongoing human activities, while any archaeological investigation should be conducted with geological
processes in mind. In this paper it is shown that 3D geological and anthropogenic models at different scales
can provide a holistic system for the management of the subsurface. It provides a framework for the
integration of other spatial and processmodels to help assess the preservationpotential for buried heritage.
Such an integrated framework model is thus contributing to a decision support system for sustainable
urban (re)development and regeneration in cities, while preserving cultural heritage. A collaborative
approach is proposed to enhance research and implementation of combined geological and archaeological
modelling for sustainable land use planning and heritage preservation, using York and Bryggen as prime
examples. This paper presents the status of 3D framework modelling at Bryggen in Norway as an example
EvoL: The new Padova T-SPH parallel code for cosmological simulations - I. Basic code: gravity and hydrodynamics
We present EvoL, the new release of the Padova N-body code for cosmological
simulations of galaxy formation and evolution. In this paper, the basic Tree +
SPH code is presented and analysed, together with an overview on the software
architectures. EvoL is a flexible parallel Fortran95 code, specifically
designed for simulations of cosmological structure formation on cluster,
galactic and sub-galactic scales. EvoL is a fully Lagrangian self-adaptive
code, based on the classical Oct-tree and on the Smoothed Particle
Hydrodynamics algorithm. It includes special features such as adaptive
softening lengths with correcting extra-terms, and modern formulations of SPH
and artificial viscosity. It is designed to be run in parallel on multiple CPUs
to optimize the performance and save computational time. We describe the code
in detail, and present the results of a number of standard hydrodynamical
tests.Comment: 33 pages, 49 figures, accepted on A&
Spatial organisation of groundwater dynamics and streamflow response from different hydropedological units in a montane catchment
Funding was provided by the Leibniz Association (SAW-2012-IGB 4167) within the International Leibniz Graduate School: Aquatic boundaries and linkages- Aqualink. We would like to thank the NRI staff for their help during field work.Peer reviewedPostprin
The Pan-STARRS Moving Object Processing System
We describe the Pan-STARRS Moving Object Processing System (MOPS), a modern
software package that produces automatic asteroid discoveries and
identifications from catalogs of transient detections from next-generation
astronomical survey telescopes. MOPS achieves > 99.5% efficiency in producing
orbits from a synthetic but realistic population of asteroids whose
measurements were simulated for a Pan-STARRS4-class telescope. Additionally,
using a non-physical grid population, we demonstrate that MOPS can detect
populations of currently unknown objects such as interstellar asteroids.
MOPS has been adapted successfully to the prototype Pan-STARRS1 telescope
despite differences in expected false detection rates, fill-factor loss and
relatively sparse observing cadence compared to a hypothetical Pan-STARRS4
telescope and survey. MOPS remains >99.5% efficient at detecting objects on a
single night but drops to 80% efficiency at producing orbits for objects
detected on multiple nights. This loss is primarily due to configurable MOPS
processing limits that are not yet tuned for the Pan-STARRS1 mission.
The core MOPS software package is the product of more than 15 person-years of
software development and incorporates countless additional years of effort in
third-party software to perform lower-level functions such as spatial searching
or orbit determination. We describe the high-level design of MOPS and essential
subcomponents, the suitability of MOPS for other survey programs, and suggest a
road map for future MOPS development.Comment: 57 Pages, 26 Figures, 13 Table
The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
The all sky surveys done by the Palomar Observatory Schmidt, the European
Southern Observatory Schmidt, and the United Kingdom Schmidt, the InfraRed
Astronomical Satellite and the 2 Micron All Sky Survey have proven to be
extremely useful tools for astronomy with value that lasts for decades. The
Wide-field Infrared Survey Explorer is mapping the whole sky following its
launch on 14 December 2009. WISE began surveying the sky on 14 Jan 2010 and
completed its first full coverage of the sky on July 17. The survey will
continue to cover the sky a second time until the cryogen is exhausted
(anticipated in November 2010). WISE is achieving 5 sigma point source
sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the
ecliptic in bands centered at wavelengths of 3.4, 4.6, 12 and 22 microns.
Sensitivity improves toward the ecliptic poles due to denser coverage and lower
zodiacal background. The angular resolution is 6.1, 6.4, 6.5 and 12.0
arc-seconds at 3.4, 4.6, 12 and 22 microns, and the astrometric precision for
high SNR sources is better than 0.15 arc-seconds.Comment: 22 pages with 19 included figures. Updated to better match the
accepted version in the A
N-body simulations of gravitational dynamics
We describe the astrophysical and numerical basis of N-body simulations, both
of collisional stellar systems (dense star clusters and galactic centres) and
collisionless stellar dynamics (galaxies and large-scale structure). We explain
and discuss the state-of-the-art algorithms used for these quite different
regimes, attempt to give a fair critique, and point out possible directions of
future improvement and development. We briefly touch upon the history of N-body
simulations and their most important results.Comment: invited review (28 pages), to appear in European Physics Journal Plu
Functional brain defects in a mouse model of a chromosomal t(1;11) translocation that disrupts DISC1 and confers increased risk of psychiatric illness
A balanced t(1;11) translocation that directly disrupts DISC1 is linked to schizophrenia and affective disorders. We previously showed that a mutant mouse, named Der1, recapitulates the effect of the translocation upon DISC1 expression. Here, RNAseq analysis of Der1 mouse brain tissue found enrichment for dysregulation of the same genes and molecular pathways as in neuron cultures generated previously from human t(1;11) translocation carriers via the induced pluripotent stem cell route. DISC1 disruption therefore apparently accounts for a substantial proportion of the effects of the t(1;11) translocation. RNAseq and pathway analysis of the mutant mouse predicts multiple Der1-induced alterations converging upon synapse function and plasticity. Synaptosome proteomics confirmed that the Der1 mutation impacts synapse composition, and electrophysiology found reduced AMPA:NMDA ratio in hippocampal neurons, indicating changed excitatory signalling. Moreover, hippocampal parvalbumin-positive interneuron density is increased, suggesting that the Der1 mutation affects inhibitory control of neuronal circuits. These phenotypes predict that neurotransmission is impacted at many levels by DISC1 disruption in human t(1;11) translocation carriers. Notably, genes implicated in schizophrenia, depression and bipolar disorder by large-scale genetic studies are enriched among the Der1-dysregulated genes, just as we previously observed for the t(1;11) translocation carrier-derived neurons. Furthermore, RNAseq analysis predicts that the Der1 mutation primarily targets a subset of cell types, pyramidal neurons and interneurons, previously shown to be vulnerable to the effects of common schizophrenia-associated genetic variants. In conclusion, DISC1 disruption by the t(1;11) translocation may contribute to the psychiatric disorders of translocation carriers through commonly affected pathways and processes in neurotransmission
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