37,998 research outputs found
Preliminary soilwater conductivity analysis to date clandestine burials of homicide victims
This study reports on a new geoscientific method to estimate the post-burial interval (PBI) and potential post-mortem interval (PMI) date of homicide victims in clandestine graves by measuring decomposition fluid conductivities. Establishing PBI/PMI dates may be critical for forensic investigators to establish time-lines to link or indeed rule out suspects to a crime. Regular in situ soilwater analysis from a simulated clandestine grave (which contained a domestic buried pig carcass) in a semi-rural environment had significantly elevated conductivity measurements when compared to background values. A temporal rapid increase of the conductivity of burial fluids was observed until one-year post-burial, after this values slowly increased until two years (end of the current study period). Conversion of x-axis from post-burial days to 'accumulated degree days' (ADDs) corrected for both local temperature variations and associated depth of burial and resulted in an improved fit for multiple linear regression analyses. ADD correction also allowed comparison with a previous conductivity grave study on a different site with a different soil type and environment; this showed comparable results with a similar trend observed. A separate simulated discovered burial had a conductivity estimated PBI date that showed 12% error from its actual burial date. Research is also applicable in examining illegal animal burials; time of burial and waste deposition. Further research is required to extend the monitoring period, to use human cadavers and to repeat this with other soil types and depositional environments
AJAX by Sophocles: A New Performance Translation
AJAX
by Sophokles
A new performance translation by Maura Giles-Watson
Directed by Ray Chambers and Lisa Berger
Original Cast
2017 Production
Old Globe/USD Shiley Graduate Theatre Program
Athena / Chorus 9: Nora Carroll
Odysseus / Chorus 10: Talley Beth Gale
Ajax: Lorenzo Landini
Chorus Leader 1: Samantha Sutliff
Chorus Leader 2: Sam Avishay
Chorus Leader 3: Larica Schnell
Chorus 4: Suzelle Palacios
Tekmessa: Christina Okolo
Angelos / Chorus 8: Jose Martinez
Teucer / Chorus 5: Renardo Pringle Jr.
Menelaus / Chorus 6: Daniel Joeck
Agamemnon / Chorus 7: Ajinkya Desai
Nicole Ries, Stage Manager
Kate Morton, Assistant Stage Manager
Maura Giles-Watson, Dramatur
Bulletin of the Massachusetts Archaeological Society, Vol. 64, No. 1
Editor’s Notes (James W. Bradley) Rediscovering the Atlatl: Observations on the Dynamics of Atlatl Design and Operation Based on Experimentation (Timothy H. Ives) A Cache of Green Points from the Pringle Site (19-MD-18), Tewksbury, MA (Eugene Winter) “I Can\u27t Read So Good, But I Like Archaeology”, Tony C.: An Educational and Public Outreach Project in the Blackstone River Valley National Heritage Corridor (Alan Leveillee and Joseph N. Waller, Jr.) An Avocational-based Site Registration: A View from New Jersey (Peter Pagoulatos) Adaptation and Resistance: A Contact Period Component at Den Rock, Lawrence, MA (Jeffrey Robert Carovillano
A study of the affect of seasonal climatic factors on the electrical resistivity response of three experimental graves
Electrical resistivity surveys have proven useful for locating clandestine graves in a number of forensic searches. However, some aspects of grave detection with resistivity surveys remain imperfectly understood. One such aspect is the effect of seasonal changes in climate on the resistivity response of graves. In this study, resistivity survey data collected over three years over three simulated graves were analysed in order to assess how the graves' resistivity anomalies varied seasonally and when they could most easily be detected. Thresholds were used to identify anomalies, and the ‘residual volume’ of grave-related anomalies was calculated as the area bounded by the relevant thresholds multiplied by the anomaly's average value above the threshold. The residual volume of a resistivity anomaly associated with a buried pig cadaver showed evidence of repeating annual patterns and was moderately correlated with the soil moisture budget. This anomaly was easiest to detect between January and April each year, after prolonged periods of high net gain in soil moisture. The resistivity response of a wrapped cadaver was more complex, although it also showed evidence of seasonal variation during the third year after burial.We suggest that the observed variation in the graves' resistivity anomalies was caused by seasonal change in survey data noise levels, which was in turn influenced by the soil moisture budget. It is possible that similar variations occur elsewhere for sites with seasonal climate variations and this could affect successful detection of other subsurface features. Further research to investigate how different climates and soil types affect seasonal variation in grave-related resistivity anomalies would be useful
Accretion and Structure of Radiating Disks
We studied a steadily accreting, geometrically thick disk model that
selfconsistently takes into account selfgravitation of the polytropic gas, its
interaction with the radiation and the mass accretion rate. The accreting mass
is injected inward in the vicinity of the central plane, where also
radiation is assumed to be created. The rest of the disk remains approximately
stationary. Only conservation laws are employed and the gas-radiation
interaction in the bulk of the disk is described in the thin-gas approximation.
We demonstrate that this scheme is numerically viable and yields a structure of
the bulk that is influenced by the radiation and (indirectly) by the prescribed
mass accretion rate. The obtained disk configurations are typical for
environments in Active Galactic Nuclei (AGN), with the central mass of the
order of 10^7 M_{\astrosun} to 10^8 M_{\astrosun}, quasi-Keplerian rotation
curves, disk masses ranging from about 10^6 M_{\astrosun} to 10^7
M_{\astrosun}, and the luminosity ranging from 10^6 L_{\astrosun} to 10^9
L_{\astrosun}. These luminosities are much lower than the corresponding
Eddington limit.Comment: Changes according to the version accepted by Astronomy & Astrophysic
Gas dynamics in whole galaxies: SPH
I review the progress of SPH calculations for modelling galaxies, and
resolving gas dynamics on GMC scales. SPH calculations first investigated the
response of isothermal gas to a spiral potential, in the absence of self
gravity and magnetic fields. Surprisingly though, even these simple
calculations displayed substructure along the spiral arms. Numerical tests
indicate that this substructure is still present at high resolution (100
million particles, ~10 pc), and is independent of the initial particle
distribution. One interpretation of the formation of substructure is that
smaller clouds can agglomerate into more massive GMCs via dissipative
collisions. More recent calculations have investigated how other processes,
such as the thermodynamics of the ISM, and self gravity affect this simple
picture. Further research has focused on developing models with a more
realistic spiral structure, either by including stars, or incorporating a tidal
interaction.Comment: 8 pages, 6 figures, review talk for IAU 270 symposium 'Computational
star formation
Disc instability in RS Ophiuchi: a path to Type Ia supernovae?
We study the stability of disc accretion in the recurrent nova RS Ophiuchi.
We construct a one-dimensional time-dependent model of the binary-disc system,
which includes viscous heating and radiative cooling and a self-consistent
treatment of the binary potential. We find that the extended accretion disc in
this system is always unstable to the thermal-viscous instability, and
undergoes repeated disc outbursts on ~10-20yr time-scales. This is similar to
the recurrence time-scale of observed outbursts in the RS Oph system, but we
show that the disc's accretion luminosity during outburst is insufficient to
explain the observed outbursts. We explore a range of models, and find that in
most cases the accretion rate during outbursts reaches or exceeds the critical
accretion rate for stable nuclear burning on the white dwarf surface.
Consequently we suggest that a surface nuclear burning triggered by disc
instability may be responsible for the observed outbursts. This allows the
white dwarf mass to grow over time, and we suggest that disc instability in RS
Oph and similar systems may represent a path to Type Ia supernovae.Comment: 8 pages, 5 figures. Accepted for publication in MNRA
Annular billiard dynamics in a circularly polarized strong laser field
We analyze the dynamics of a valence electron of the buckminsterfullerene
molecule (C60) subjected to a circularly polarized laser field by modeling it
with the motion of a classical particle in an annular billiard. We show that
the phase space of the billiard model gives rise to three distinct
trajectories: "Whispering gallery orbits", which only hit the outer billiard
wall, "daisy orbits" which hit both billiard walls (while rotating solely
clockwise or counterclockwise for all time), and orbits which only visit the
downfield part of the billiard, as measured relative to the laser term. These
trajectories, in general, maintain their distinct features, even as intensity
is increased from 10^10 to 10^14 W*cm^-2. We attribute this robust separation
of phase space to the existence of twistless tori
Technology evaluation of control/monitoring systems for MIUS application
Potential ways of providing control and monitoring for the Modular Integrated Utility System (MIUS) program are elaborated. Control and monitoring hardware and operational systems are described. The requirements for the MIUS program and the development requirements are discussed
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