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FLUOR HANFORDS APPROACH TO INTEGRATED SAFETY MANAGEMENT WORKER ENGAGEMENT 1996 - 2009
Hard thermal loops for soft or collinear external momenta
We consider finite temperature 1-loop diagrams with hard loop momenta and an
arbitrary number of external gauge fields when the external momenta are either
soft, or near the light cone and nearly collinear with the loop momentum. We
obtain a recursion relation for these diagrams which we translate into an
equation for their generating functional. By integrating out the soft fields
while keeping two collinear ones we find an integral equation, originally due
to Arnold, Moore, and Yaffe, which sums the bremsstrahlung and pair
annihilation contribution to the thermal photon production rate.Comment: 17 pages, title corrected, clarifying paragraph added to the
appendix, version to appear in JHE
Bjorken Flow, Plasma Instabilities, and Thermalization
At asymptotically high energies, thermalization in heavy ion collisions can
be described via weak-coupling QCD. We present a complete treatment of how
thermalization proceeds, at the parametric weak-coupling level. We show that
plasma instabilities dominate the dynamics, from immediately after the
collision until well after the plasma becomes nearly in equilibrium. Initially
they drive the system close to isotropy, but Bjorken expansion and increasing
diluteness makes the system again become more anisotropic. At time \tau ~
\alpha^(-12/5) Q^(-1) the dynamics become dominated by a nearly-thermal bath;
and at time \tau ~ \alpha^(-5/2) Q^(-1)$ the bath comes to dominate the energy
density, completing thermalization. After this time there is a nearly isotropic
and thermal Quark-Gluon Plasma.Comment: 22 pages, 5 figure
Thermalization in Weakly Coupled Nonabelian Plasmas
We investigate how relativistic, nonabelian plasmas approach equilibrium in a
general context. Our treatment is entirely parametric and for small Yang-Mills
coupling . First we study isotropic systems with an initially
nonequilibrium momentum distribution. We consider both the case of initially
very high occupancy and initially very low occupancy. Then we consider systems
which are anisotropic. We consider both weak anisotropy and large anisotropy,
and allow the occupancy to be parametrically large or small. Writing the
typical momentum of an initial excitation as Q and the final temperature as T,
full equilibration occurs in a time t ~ \alpha^{-2}/T for T > Q, and t ~
\alpha^{-2} Q^{1/2} T^{-3/2} for T < Q, unless the initial system is
sufficiently anisotropic and T > \alpha^{2/3} Q, in which case equilibration
occurs somewhat faster, t ~ \alpha^{-13/7} Q^{5/7} T^{-12/7} (or \alpha^{-2}/T
if that is longer).Comment: 55 pages including many figures, but with a comprehensive review of
results in the first 6 pages
Three "universal" mesoscopic Josephson effects
1. Introduction
2. Supercurrent from Excitation Spectrum
3. Excitation Spectrum from Scattering Matrix
4. Short-Junction Limit
5. Universal Josephson Effects
5.1 Quantum Point Contact
5.2 Quantum Dot
5.3 Disordered Point Contact (Average supercurrent, Supercurrent
fluctuations)Comment: 21 pages, 2 figures; legacy revie
Optimizing the colour and fabric of targets for the control of the tsetse fly Glossina fuscipes fuscipes
Background:
Most cases of human African trypanosomiasis (HAT) start with a bite from one of the subspecies of Glossina fuscipes. Tsetse use a range of olfactory and visual stimuli to locate their hosts and this response can be exploited to lure tsetse to insecticide-treated targets thereby reducing transmission. To provide a rational basis for cost-effective designs of target, we undertook studies to identify the optimal target colour.
Methodology/Principal Findings:
On the Chamaunga islands of Lake Victoria , Kenya, studies were made of the numbers of G. fuscipes fuscipes attracted to targets consisting of a panel (25 cm square) of various coloured fabrics flanked by a panel (also 25 cm square) of fine black netting. Both panels were covered with an electrocuting grid to catch tsetse as they contacted the target. The reflectances of the 37 different-coloured cloth panels utilised in the study were measured spectrophotometrically. Catch was positively correlated with percentage reflectance at the blue (460 nm) wavelength and negatively correlated with reflectance at UV (360 nm) and green (520 nm) wavelengths. The best target was subjectively blue, with percentage reflectances of 3%, 29%, and 20% at 360 nm, 460 nm and 520 nm respectively. The worst target was also, subjectively, blue, but with high reflectances at UV (35% reflectance at 360 nm) wavelengths as well as blue (36% reflectance at 460 nm); the best low UV-reflecting blue caught 3Ă— more tsetse than the high UV-reflecting blue.
Conclusions/Significance:
Insecticide-treated targets to control G. f. fuscipes should be blue with low reflectance in both the UV and green bands of the spectrum. Targets that are subjectively blue will perform poorly if they also reflect UV strongly. The selection of fabrics for targets should be guided by spectral analysis of the cloth across both the spectrum visible to humans and the UV region
Thermodynamics and Instabilities of a Strongly Coupled Anisotropic Plasma
We extend our analysis of a IIB supergravity solution dual to a spatially
anisotropic finite-temperature N=4 super Yang-Mills plasma. The solution is
static, possesses an anisotropic horizon, and is completely regular. The full
geometry can be viewed as a renormalization group flow from an AdS geometry in
the ultraviolet to a Lifshitz-like geometry in the infrared. The anisotropy can
be equivalently understood as resulting from a position-dependent theta-term or
from a non-zero number density of dissolved D7-branes. The holographic stress
tensor is conserved and anisotropic. The presence of a conformal anomaly plays
an important role in the thermodynamics. The phase diagram exhibits homogeneous
and inhomogeneous (i.e. mixed) phases. In some regions the homogeneous phase
displays instabilities reminiscent of those of weakly coupled plasmas. We
comment on similarities with QCD at finite baryon density and with the
phenomenon of cavitation.Comment: 62 pages, 13 figures; v2: typos fixed, added reference
Naturalised Vitis Rootstocks in Europe and Consequences to Native Wild Grapevine
The genus Vitis is represented by several coexisting species in Europe. Our study focuses on naturalised rootstocks that originate in viticulture. The consequences of their presence to the landscape and to native European species (Vitis vinifera ssp. silvestris) are evaluated. This study compares ecological traits (seven qualitative and quantitative descriptors) and the genetic diversity (10 SSR markers) of populations of naturalised rootstocks and native wild grapevines. 18 large naturalised rootstock populations were studied in the RhĂ´ne watershed. Wild European grapevines are present in four main habitats (screes, alluvial forests, hedges, and streamside hedges). In contrast, naturalised rootstock populations are mainly located in alluvial forests, but they clearly take advantage of alluvial system dynamics and connectivity at the landscape level. These latter populations appear to reproduce sexually, and show a higher genetic diversity than Vitis vinifera ssp. silvestris. The regrouping of naturalised rootstocks in interconnected populations tends to create active hybrid swarms of rootstocks. The rootstocks show characters of invasive plants. The spread of naturalised rootstocks in the environment, the acceleration of the decline of the European wild grapevine, and the propagation of genes of viticultural interest in natural populations are potential consequences that should be kept in mind when undertaking appropriate management measures
The Echinococcus canadensis (G7) genome: A key knowledge of parasitic platyhelminth human diseases
Background: The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. Results: We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. Conclusions: This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high-quality genome assembly is critical for fully exploring the biology of a pathogenic organism. The E. canadensis (G7) genome presented in this study provides a unique opportunity to address the genetic diversity among the genus Echinococcus and its particular developmental features. At present, there is no unequivocal taxonomic classification of Echinococcus species; however, the genome-wide SNPs analysis performed here revealed the phylogenetic distance among these three Echinococcus species. Additional cestode genomes need to be sequenced to be able to resolve their phylogeny.Fil: Maldonado, Lucas Luciano. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Assis, Juliana. FundaciĂłn Oswaldo Cruz; BrasilFil: Gomes AraĂşjo, Flávio M.. FundaciĂłn Oswaldo Cruz; BrasilFil: Salim, Anna C. M.. FundaciĂłn Oswaldo Cruz; BrasilFil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Camicia, Federico. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Fox, Adolfo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Oliveira, Guilherme. Instituto TecnolĂłgico Vale; Brasil. FundaciĂłn Oswaldo Cruz; BrasilFil: Kamenetzky, Laura. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; Argentin
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