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Microbial Field Pilot Study
This report covers progress made during the first year of the Microbial Field Pilot Study project. Information on reservoir ecology and characterization, facility and treatment design, core experiments, bacterial mobility, and mathematical modeling are addressed. To facilitate an understanding of the ecology of the target reservoir analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. A preliminary design of facilities for the operation of the field pilot test was prepared. In addition, procedures for facilities installation and for injection treatments are described. The Southeast Vassar Vertz Sand Unit (SEVVSU), the site of the proposed field pilot study, is described physically, historically, and geologically. The fields current status is presented and the ongoing reservoir simulation is discussed. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. Two possible mechanisms, relative permeability effects and changes in the capillary number, are discussed and related to four Berea core experiments' results. The experiments were conducted at reservoir temperature using SEVVSU oil, brine, and bacteria. The movement and activity of bacteria in porous media were investigated by monitoring the growth of bacteria in sandpack cores under no flow conditions. The rate of bacteria advancement through the cores was determined. A mathematical model of the MEOR process has been developed. The model is a three phase, seven species, one dimensional model. Finite difference methods are used for solution. Advection terms in balance equations are represented with a third- order upwind differencing scheme to reduce numerical dispersion and oscillations. The model is applied to a batch fermentation example. 52 refs., 26 figs., 21 tabs
Two different quasiparticle scattering rates in vortex line liquid phase of layered d-wave superconductors
We carry out a quantum mechanical analysis of the behavior of nodal
quasiparticles in the vortex line liquid phase of planar d-wave
superconductors. Applying a novel path integral technique we calculate a number
of experimentally relevant observables and demonstrate that in the low-field
regime the quasiparticle scattering rates deduced from photoemission and
thermal transport data can be markedly different from that extracted from
tunneling, specific heat, superfluid stiffness or spin-lattice relaxation time.Comment: Latex, 4 pages, no figure
Biomass increases go under cover : woody vegetation dynamics in South African rangelands
Woody biomass dynamics are an expression of ecosystem function, yet biomass estimates
do not provide information on the spatial distribution of woody vegetation within the vertical
vegetation subcanopy. We demonstrate the ability of airborne light detection and ranging
(LiDAR) to measure aboveground biomass and subcanopy structure, as an explanatory
tool to unravel vegetation dynamics in structurally heterogeneous landscapes. We sampled
three communal rangelands in Bushbuckridge, South Africa, utilised by rural communities
for fuelwood harvesting. Woody biomass estimates ranged between 9 Mg ha-1 on gabbro
geology sites to 27 Mg ha-1 on granitic geology sites. Despite predictions of woodland depletion
due to unsustainable fuelwood extraction in previous studies, biomass in all the communal
rangelands increased between 2008 and 2012. Annual biomass productivity
estimates (10â14% p.a.) were higher than previous estimates of 4% and likely a significant
contributor to the previous underestimations of modelled biomass supply. We show that biomass
increases are attributable to growth of vegetation <5 m in height, and that, in the high
wood extraction rangeland, 79% of the changes in the vertical vegetation subcanopy are
gains in the 1-3m height class. The higher the wood extraction pressure on the rangelands,
the greater the biomass increases in the low height classes within the subcanopy, likely a
strong resprouting response to intensive harvesting. Yet, fuelwood shortages are still occurring,
as evidenced by the losses in the tall tree height class in the high extraction rangeland. Loss of large trees and gain in subcanopy shrubs could result in a structurally simple landscape
with reduced functional capacity. This research demonstrates that intensive harvesting
can, paradoxically, increase biomass and this has implications for the sustainability of ecosystem service provision. The structural implications of biomass increases in communal
rangelands could be misinterpreted as woodland recovery in the absence of three-dimensional,
subcanopy information.S1 Dataset. Biomass model data. Data include 2012 LiDAR-derived average height and canopy
cover extraction metrics, as well as field-work based allometry. Each line item is per 25 m x
25 m grid cell. Metadata are included in the dataset.S2 Dataset. Biomass and subcanopy data. Data include 2008 and 2012 biomass estimates derived
from biomass models as well as % subcanopy returns for voxel data for the height class
categories: 1-3m, 3-5m, 5-10m and >10m. Each line item is per 25 m x 25 m grid cell. Data are
organized per land extraction category into separate worksheets. Metadata are included in
the dataset.S3 Dataset. Biomass changes (Mg ha-1) in relation to relative height and canopy cover
change. Data include biomass change estimates (2008â2012), percentage height and canopy
cover changes for each 25 m x 25 m grid cell. Each height class (relative to height in 2008) are
shown on separate worksheets. Metadata are included in the dataset.S1 Fig. Site-specific biomass model residuals. The residual spread demonstrates heteroskedasticity
with increasing biomass fitted values for rangelands with a) high, b) intermediate and
c) low extraction pressure.S2 Fig. Biomass changes (%) relative to height-specific change in subcanopy returns (%).
Height categories are: 1â3 m, 3â5 m, 5â10 m and >10 m.The Carnegie Airborne Observatory (CAO)
is made possible by the Avatar Alliance Foundation,
Margaret A. Cargill Foundation, John D. and
Catherine T. MacArthur Foundation, Grantham
Foundation for the Protection of the Environment, W.
M. Keck Foundation, Gordon and Betty Moore
Foundation, Mary Anne Nyburg Baker and G.
Leonard Baker, Jr., and William R. Hearst III.
Application of the CAO data in South Africa is made possible through the Andrew Mellon Foundation and
the endowment of the Carnegie Institution for
Science, the Council for Scientific and Industrial
Research (CSIR), and the South African Department
of Science and Technology (grant agreement DST/
CON 0119/2010, Earth Observation Application
Development in Support of SAEOS). CSIR coauthors
are supported by the European Unionâs
Seventh Framework Programme (FP7/2007-2013,
grant agreement n°282621, AGRICAB). PJM
acknowledges funding from the National Research
Foundation (NRF: SFH1207203615). Additionally,
PJM and ETFW acknowledge the DST-NRF Centre
of Excellence in Tree Health Biotechnology (CTHB)
and, PJM and BFNE, the Applied Centre for Climate
and Earth Systems Science (ACCESS). BFNE
acknowledges financial support from Exxaro.http://www.plosone.orgam201
Distinct patterns of ÎFosB induction in brain by drugs of abuse
The transcription factor ÎFosB accumulates and persists in brain in response to chronic stimulation. This accumulation after chronic exposure to drugs of abuse has been demonstrated previously by Western blot most dramatically in striatal regions, including dorsal striatum (caudate/putamen) and nucleus accumbens. In the present study, we used immunohistochemistry to define with greater anatomical precision the induction of ÎFosB throughout the rodent brain after chronic drug treatment. We also extended previous research involving cocaine, morphine, and nicotine to two additional drugs of abuse, ethanol and Î9-tetrahydrocannabinol (Î9-THC, the active ingredient in marijuana). We show here that chronic, but not acute, administration of each of four drugs of abuse, cocaine, morphine, ethanol, and Î9-THC, robustly induces ÎFosB in nucleus accumbens, although different patterns in the core vs. shell subregions of this nucleus were apparent for the different drugs. The drugs also differed in their degree of ÎFosB induction in dorsal striatum. In addition, all four drugs induced ÎFosB in prefrontal cortex, with the greatest effects observed with cocaine and ethanol, and all of the drugs induced ÎFosB to a small extent in amygdala. Furthermore, all drugs induced ÎFosB in the hippocampus, and, with the exception of ethanol, most of this induction was seen in the dentate. Lower levels of ÎFosB induction were seen in other brain areas in response to a particular drug treatment. These findings provide further evidence that induction of ÎFosB in nucleus accumbens is a common action of virtually all drugs of abuse and that, beyond nucleus accumbens, each drug induces ÎFosB in a region-specific manner in brain
The Evolutionary and Phylogeographic History of Woolly Mammoths: A Comprehensive Mitogenomic Analysis
Near the end of the Pleistocene epoch, populations of the woolly mammoth (Mammuthus primigenius) were distributed across parts of three continents, from western Europe and northern Asia through Beringia to the Atlantic seaboard of North America. Nonetheless, questions about the connectivity and temporal continuity of mammoth populations and species remain unanswered. We use a combination of targeted enrichment and high-throughput sequencing to assemble and interpret a data set of 143 mammoth mitochondrial genomes, sampled from fossils recovered from across their Holarctic range. Our dataset includes 54 previously unpublished mitochondrial genomes and significantly increases the coverage of the Eurasian range of the species. The resulting global phylogeny confirms that the Late Pleistocene mammoth population comprised three distinct mitochondrial lineages that began to diverge âŒ1.0-2.0 million years ago (Ma). We also find that mammoth mitochondrial lineages were strongly geographically partitioned throughout the Pleistocene. In combination, our genetic results and the pattern of morphological variation in time and space suggest that male-mediated gene flow, rather than large-scale dispersals, was important in the Pleistocene evolutionary history of mammoths
The PHENIX Experiment at RHIC
The physics emphases of the PHENIX collaboration and the design and current
status of the PHENIX detector are discussed. The plan of the collaboration for
making the most effective use of the available luminosity in the first years of
RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program
available at http://www.rhic.bnl.gov/phenix
Spectroscopic target selection for the Sloan Digital Sky Survey: The luminous red galaxy sample
We describe the target selection and resulting properties of a spectroscopic sample of luminous red galaxies (LRGs) from the imaging data of the Sloan Digital Sky Survey (SDSS). These galaxies are selected on the basis of color and magnitude to yield a sample of luminous intrinsically red galaxies that extends fainter and farther than the main flux-limited portion of the SDSS galaxy spectroscopic sample. The sample is designed to impose a passively evolving luminosity and rest-frame color cut to a redshift of 0.38. Additional, yet more luminous red galaxies are included to a redshift of âŒ0.5. Approximately 12 of these galaxies per square degree are targeted for spectroscopy, so the sample will number over 100,000 with the full survey. SDSS commissioning data indicate that the algorithm efficiently selects luminous (M*g â - 21.4) red galaxies, that the spectroscopic success rate is very high, and that the resulting set of galaxies is approximately volume limited out to z = 0.38. When the SDSS is complete, the LRG spectroscopic sample will fill over 1 h-3 Gpc3 with an approximately homogeneous population of galaxies and will therefore be well suited to studies of large-scale structure and clusters out to z = 0.5
Desempenho, composição do leite e metabĂłlitos sanguĂneos de vacas HolandĂȘs x Gir manejadas em pastagem de Brachiaria brizantha cv. Marandu e suplementadas com grĂŁo de soja tostado
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