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Stratigraphic Studies of the Palo Duro Basin: An Update
Stratigraphic studies of the Palo Duro Basin are now in their 8th year. Although the emphasis in these studies now lies in the San Andres Formation (possible repository host rock) and the Wolfcamp Series (sub-repository aquifer), investigations of other units (fig. 1) continue to be carried out as well. This report includes work that was not available for inclusion in last year's (1983) CSR on stratigraphy (Open File Report No. OF-WTWI-1984-30). The section on pre-Pennsylvanian stratigraphy represents the final stages of study of those units. The report detailing structural controls on deposition of the San Andres is part of an ongoing effort to recognize indications of structural or tectonic controls on sedimentation throughout the stratigraphic column in the Palo Duro Basin area. Studies of the Dockum Group are revealing similar controls during the Triassic. Core studies of the Dockum are increasing our resolution of depositional settings in the area.Bureau of Economic Geolog
Biochemical Systematics of Notothenioid Fishes from Antarctica
Genetic variation at 30 protein-coding loci was examined in seven forms of notothenioid fishes from Antarctica. Multilocus heterozygosity varied from 0.018 to 0.078 across taxa. An analysis of the allozyme data revealed the probable existence of an unrecognized cryptic species within Trematomu5 bemacchii. Pagothenia borchgrevinki is as closely related to some species of Trematomus as are some species of Trematomus to each other. Speciation among the species of Trematomus and Pagothenia appears to have taken place primarily after the separation of Antarctica from Australia
XO-5b: A Transiting Jupiter-sized Planet With A Four Day Period
The star XO-5 (GSC 02959-00729, V=12.1, G8V) hosts a Jupiter-sized,
Rp=1.15+/-0.12 Rjup, transiting extrasolar planet, XO-5b, with an orbital
period of P=4.187732+/-0.00002 days. The planet mass (Mp=1.15+/-0.08 Mjup) and
surface gravity (gp=22+/-5 m/s^2) are significantly larger than expected by
empirical Mp-P and Mp-P-[Fe/H] relationships. However, the deviation from the
Mp-P relationship for XO-5b is not large enough to suggest a distinct type of
planet as is suggested for GJ 436b, HAT-P-2b, and XO-3b. By coincidence XO-5
overlies the extreme H I plume that emanates from the interacting galaxy pair
NGC 2444/NGC 2445 (Arp 143).Comment: 10 pages, 9 Figures, Submitted to Ap
Athena\u27s Prism - A Diplomatic Strategy Role Playing Simulation for Generating Ideas and Exploring Alternatives
Intelligence analysts must clear at least three hurdles to get good product out the door: cognitive biases, social biases and self-imposed organizational impediments. Others (e.g., Gilovich, et al., Heuer, and Kahneman and Tversky), explain the cognitive processes that can help or trip us. A less well mapped set of dangers arises in the social dynamics of communicating tasking, working with other analysts, editing and customer interaction. Finally, the mere fact of a unit\u27s published record creates analytic inertia - an argument at rest tends to stay at rest and one in motion (i.e., ambiguous or uncertain) tends to stay in motion. (A variation of this includes groupthink.
MRI and gravimetric studies of hydrology in drip irrigated heaps and its effect on the propagation of bioleaching microorganisms
Heap bioleaching performance is dependent on the contacting of the leach solution with the ore bed, hence on the system hydrodynamics. In this study two experimental setups were used to examine hydrodynamics associated with irrigation from a single drip emitter, one of the most common methods of heap irrigation. A specialist magnetic resonance imaging (MRI) method which is insensitive to the metal content of the ore was used to examine the liquid flow into an ore bed in the immediate vicinity of an irrigation point. The distribution of liquid in, microbial colonisation of and mineral recovery from a bioleach of a large scale 132 kg “ore slice” were subsequently monitored using sample ports positioned along the breadth and height of the reactor. In both systems the lateral movement of the liquid increased with bed depth, though preferential flow was evident. The majority of the liquid flow was in the region directly below the irrigation point and almost no liquid exchange occurred in the areas of lowest liquid content at the upper corners of the bed in which fluid exchange was driven by capillary action. The MRI studies revealed that the liquid distribution was unchanging following an initial settling of the ore bed and that, at steady state, the majority (~60%) of the liquid flowed directly into established large channels. The limited lateral movement of the liquid had a significant impact on the local leaching efficiencies and microbial colonisation of the ore with cell concentrations in the regions of lowest liquid content lying below the detection limit. Hence poor lateral liquid distribution with drip irrigation, and the associated impact on colonisation was identified as a significant disadvantage of this irrigation approach. Further, the need to optimise fluid exchange throughout the ore bed was identified as key for optimisation of leaching performance
Determining Optimum Soil Type and Salinity for Rearing the Federally Endangered Salt Creek Tiger Beetle, \u3ci\u3eCicindela (Ellipsoptera) nevadica lincolniana\u3c/i\u3e Casey (Coleoptera: Carabidae: Cicindelinae)
Effective rearing methods are needed to recover the federally endangered Salt Creek tiger beetle, Cicindela (Ellipsoptera) nevadica lincolniana Casey, a subspecies that occurs exclusively in saline wetlands and seeps along Little Salt Creek in Lancaster County, Nebraska. Experiments were initiated to determine soil type and salinity concentrations appropriate for stimulating female oviposition in laboratory settings to produce larvae and/or adults for reintroduction to native habitats. In 2013, there were highly significant differences between native soil and a sand/loess soil mixture, but no differences between two salinity levels, 0.354 M and 0.5 M. In 2014, using only a sand/loess soil mixture, there were again no differences between the test salinity levels. A sand/loess soil mixture of either 0.354M or 0.5M salinity was determined to be optimum for egg production
Determining Optimum Soil Type and Salinity for Rearing the Federally Endangered Salt Creek Tiger Beetle, \u3ci\u3eCicindela (Ellipsoptera) nevadica lincolniana\u3c/i\u3e Casey (Coleoptera: Carabidae: Cicindelinae)
Effective rearing methods are needed to recover the federally endangered Salt Creek tiger beetle, Cicindela (Ellipsoptera) nevadica lincolniana Casey, a subspecies that occurs exclusively in saline wetlands and seeps along Little Salt Creek in Lancaster County, Nebraska. Experiments were initiated to determine soil type and salinity concentrations appropriate for stimulating female oviposition in laboratory settings to produce larvae and/or adults for reintroduction to native habitats. In 2013, there were highly significant differences between native soil and a sand/loess soil mixture, but no differences between two salinity levels, 0.354 M and 0.5 M. In 2014, using only a sand/loess soil mixture, there were again no differences between the test salinity levels. A sand/loess soil mixture of either 0.354M or 0.5M salinity was determined to be optimum for egg production
Ground-layer wavefront reconstruction from multiple natural guide stars
Observational tests of ground layer wavefront recovery have been made in open
loop using a constellation of four natural guide stars at the 1.55 m Kuiper
telescope in Arizona. Such tests explore the effectiveness of wide-field seeing
improvement by correction of low-lying atmospheric turbulence with ground-layer
adaptive optics (GLAO). The wavefronts from the four stars were measured
simultaneously on a Shack-Hartmann wavefront sensor (WFS). The WFS placed a 5 x
5 array of square subapertures across the pupil of the telescope, allowing for
wavefront reconstruction up to the fifth radial Zernike order. We find that the
wavefront aberration in each star can be roughly halved by subtracting the
average of the wavefronts from the other three stars. Wavefront correction on
this basis leads to a reduction in width of the seeing-limited stellar image by
up to a factor of 3, with image sharpening effective from the visible to near
infrared wavelengths over a field of at least 2 arc minutes. We conclude that
GLAO correction will be a valuable tool that can increase resolution and
spectrographic throughput across a broad range of seeing-limited observations.Comment: 25 pages, 8 figures, to be published in Astrophys.
X-raying the Beating Heart of a Newborn Star: Rotational Modulation of High-energy Radiation from V1647 Ori
We report a periodicity of ~1 day in the highly elevated X-ray emission from
the protostar V1647 Ori during its two recent multiple-year outbursts of mass
accretion. This periodicity is indicative of protostellar rotation at
near-breakup speed. Modeling of the phased X-ray light curve indicates the
high-temperature (~50 MK), X-ray-emitting plasma, which is most likely heated
by accretion-induced magnetic reconnection, resides in dense (>~5e10 cm-3),
pancake-shaped magnetic footprints where the accretion stream feeds the newborn
star. The sustained X-ray periodicity of V1647 Ori demonstrates that such
protostellar magnetospheric accretion configurations can be stable over
timescales of years.Comment: 26 pages, 10 figure
XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary
We report on a V=11.2 early K dwarf, XO-2 (GSC 03413-00005), that hosts a
Rp=0.98+0.03/-0.01 Rjup, Mp=0.57+/-0.06 Mjup transiting extrasolar planet,
XO-2b, with an orbital period of 2.615857+/-0.000005 days. XO-2 has high
metallicity, [Fe/H]=0.45+/-0.02, high proper motion, mu_tot=157 mas/yr, and has
a common proper motion stellar companion with 31" separation. The two stars are
nearly identical twins, with very similar spectra and apparent magnitudes. Due
to the high metallicity, these early K dwarf stars have a mass and radius close
to solar, Ms=0.98+/-0.02 Msolar and Rs=0.97+0.02/-0.01 Rsolar. The high proper
motion of XO-2 results from an eccentric orbit (Galactic pericenter, Rper<4
kpc) well confined to the Galactic disk (Zmax~100 pc). In addition, the phase
space position of XO-2 is near the Hercules dynamical stream, which points to
an origin of XO-2 in the metal-rich, inner Thin Disk and subsequent dynamical
scattering into the solar neighborhood. We describe an efficient Markov Chain
Monte Carlo algorithm for calculating the Bayesian posterior probability of the
system parameters from a transit light curve.Comment: 14 pages, 10 Figures, Accepted in ApJ. Negligible changes to XO-2
system properties. Removed Chi^2 light curve analysis section, and simplified
MCMC light curve analysis discussio
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