1,585 research outputs found

    The role of civil affairs in unconventional warfare

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    With the renewed focus on Unconventional Warfare as a means of achieving U.S. Foreign and National Security Policy goals, the U.S. Army Special Operations Command Civil Affairs force must assess its capability to conduct Civil Affairs operations in support of an Unconventional Warfare campaign. This thesis examines Civil Affairs current role and surveys past conflicts to explore Civil Affairs potential role in all phases of Unconventional Warfare. It assumes that political and logistical networks are the keys to building and sustaining a revolutionary movement. This thesis answers the following questions How can Civil Affairs forces in place now and deployed for an operation identify, develop and motivate revolutionary networks that can be activated to sustain a revolution and fulfill U.S. policy needs within a foreign nation How can Civil Affairs doctrine be revised to better support these taskshttp://archive.org/details/theroleofcivilff1094527789Master Sergeant, United States ArmyMajor, United States ArmyApproved for public release; distribution is unlimited

    Unusual Metabolism and Hypervariation in the Genome of a Gracilibacterium (BD1-5) from an Oil-Degrading Community.

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    The candidate phyla radiation (CPR) comprises a large monophyletic group of bacterial lineages known almost exclusively based on genomes obtained using cultivation-independent methods. Within the CPR, Gracilibacteria (BD1-5) are particularly poorly understood due to undersampling and the inherent fragmented nature of available genomes. Here, we report the first closed, curated genome of a gracilibacterium from an enrichment experiment inoculated from the Gulf of Mexico and designed to investigate hydrocarbon degradation. The gracilibacterium rose in abundance after the community switched to dominance by Colwellia Notably, we predict that this gracilibacterium completely lacks glycolysis, the pentose phosphate and Entner-Doudoroff pathways. It appears to acquire pyruvate, acetyl coenzyme A (acetyl-CoA), and oxaloacetate via degradation of externally derived citrate, malate, and amino acids and may use compound interconversion and oxidoreductases to generate and recycle reductive power. The initial genome assembly was fragmented in an unusual gene that is hypervariable within a repeat region. Such extreme local variation is rare but characteristic of genes that confer traits under pressure to diversify within a population. Notably, the four major repeated 9-mer nucleotide sequences all generate a proline-threonine-aspartic acid (PTD) repeat. The genome of an abundant Colwellia psychrerythraea population has a large extracellular protein that also contains the repeated PTD motif. Although we do not know the host for the BD1-5 cell, the high relative abundance of the C. psychrerythraea population and the shared surface protein repeat may indicate an association between these bacteria.IMPORTANCE CPR bacteria are generally predicted to be symbionts due to their extensive biosynthetic deficits. Although monophyletic, they are not monolithic in terms of their lifestyles. The organism described here appears to have evolved an unusual metabolic platform not reliant on glucose or pentose sugars. Its biology appears to be centered around bacterial host-derived compounds and/or cell detritus. Amino acids likely provide building blocks for nucleic acids, peptidoglycan, and protein synthesis. We resolved an unusual repeat region that would be invisible without genome curation. The nucleotide sequence is apparently under strong diversifying selection, but the amino acid sequence is under stabilizing selection. The amino acid repeat also occurs in a surface protein of a coexisting bacterium, suggesting colocation and possibly interdependence

    Thermal tides in the Martian middle atmosphere as seen by the Mars Climate Sounder

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    The first systematic observations of the middle atmosphere of Mars (35–80km) with the Mars Climate Sounder (MCS) show dramatic patterns of diurnal thermal variation, evident in retrievals of temperature and water ice opacity. At the time of writing, the data set of MCS limb retrievals is sufficient for spectral analysis within a limited range of latitudes and seasons. This analysis shows that these thermal variations are almost exclusively associated with a diurnal thermal tide. Using a Martian general circulation model to extend our analysis, we show that the diurnal thermal tide dominates these patterns for all latitudes and all seasons

    Radio Galaxy Zoo: Cosmological Alignment of Radio Sources

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    We study the mutual alignment of radio sources within two surveys, FIRST and TGSS. This is done by producing two position angle catalogues containing the preferential directions of respectively 3005930\,059 and 1167411\,674 extended sources distributed over more than 70007\,000 and 1700017\,000 square degrees. The identification of the sources in the FIRST sample was performed in advance by volunteers of the Radio Galaxy Zoo project, while for the TGSS sample it is the result of an automated process presented here. After taking into account systematic effects, marginal evidence of a local alignment on scales smaller than 2.5deg2.5\deg is found in the FIRST sample. The probability of this happening by chance is found to be less than 22 per cent. Further study suggests that on scales up to 1.5deg1.5\deg the alignment is maximal. For one third of the sources, the Radio Galaxy Zoo volunteers identified an optical counterpart. Assuming a flat Λ\LambdaCDM cosmology with Ωm=0.31,ΩΛ=0.69\Omega_m = 0.31, \Omega_\Lambda = 0.69, we convert the maximum angular scale on which alignment is seen into a physical scale in the range [19,38][19, 38] Mpc h701h_{70}^{-1}. This result supports recent evidence reported by Taylor and Jagannathan of radio jet alignment in the 1.41.4 deg2^2 ELAIS N1 field observed with the Giant Metrewave Radio Telescope. The TGSS sample is found to be too sparsely populated to manifest a similar signal
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