340 research outputs found
Local genomic adaptation of coral reef-associated microbiomes to gradients of natural variability and anthropogenic stressors
Holobionts are species-specific associations between macro- and microorganisms. On coral reefs, the benthic coverage of coral and algal holobionts varies due to natural and anthropogenic forcings. Different benthic macroorganisms are predicted to have specific microbiomes. In contrast, local environmental factors are predicted to select for specific metabolic pathways in microbes. To reconcile these two predictions, we hypothesized that adaptation of microbiomes to local conditions is facilitated by the horizontal transfer of genes responsible for specific metabolic capabilities. To test this hypothesis, microbial metagenomes were sequenced from 22 coral reefs at 11 Line Islands in the central Pacific that together span a wide range of biogeochemical and anthropogenic influences. Consistent with our hypothesis, the percent cover of major benthic functional groups significantly correlated with particular microbial taxa. Reefs with higher coral cover had a coral microbiome with higher abundances of Alphaproteobacteria (such as Rhodobacterales and Sphingomonadales), whereas microbiomes of algae-dominated reefs had higher abundances of Gammaproteobacteria (such as Alteromonadales, Pseudomonadales, and Vibrionales), Betaproteobacteria, and Bacteriodetes. In contrast to taxa, geography was the strongest predictor of microbial community metabolism. Microbial communities on reefs with higher nutrient availability (e.g., equatorial upwelling zones) were enriched in genes involved in nutrient-related metabolisms (e.g., nitrate and nitrite ammonification, Ton/Tol transport, etc.). On reefs further from the equator, microbes had more genes encoding chlorophyll biosynthesis and photosystems I/II. These results support the hypothesis that core microbiomes are determined by holobiont macroorganisms, and that those core taxa adapt to local conditions by selecting for advantageous metabolic genes
Vismodegib voor gevorderd basaalcelcarcinoom:Doelgerichte behandeling bij lokaal uitgebreide of gemetastaseerde tumoren
Legal Steps Outside the Climate Convention: Litigation as a Tool to Address Climate Change
This article examines the recent academic interest in litigation as a tool to address climate change, as well as the surge of legal actions worldwide to bring the problem to the attention of judiciaries. This new interest reveals the frustration of legal scholars and activists at the slow rate at which policy makers are addressing the climate change problem. This article shows the slow build-up of academic interest in litigation, before moving on to analyse the kinds of legal causes of action that are being used in different parts of the world. Most of these cases have not been fully resolved, and it is more than likely that the judgments may not always be favourable to the plaintiffs, but at least a first step has been made to involve yet another forum for addressing the climate change problem. © 2007 The Author. Journal compilation © 2007 Blackwell Publishing Ltd
Measurement of Exclusive rho+rho- Production in Mid-Virtuality Two-Photon Interactions and Study of the gamma gamma* -> rho rho Process at LEP
Exclusive rho+rho- production in two-photon collisions between a quasi-real
photon, gamma, and a mid-virtuality photon, gamma*, is studied with data
collected at LEP at centre-of-mass energies root(s)=183-209GeV with a total
integrated luminosity of 684.8pb^-1. The cross section of the gamma gamma* ->
rho+ rho- process is determined as a function of the photon virtuality, Q^2,
and the two-photon centre-of-mass energy, W_gg, in the kinematic region:
0.2GeV^2 < Q^2 <0.85GeV^2 and 1.1GeV < W_gg < 3GeV. These results, together
with previous L3 measurements of rho0 rho0 and rho+ rho- production, allow a
study of the gamma gamma* -> rho rho process over the Q^2-region 0.2GeV^2 < Q^2
< 30 GeV^2
Inclusive Lambda Production in Two-Photon Collisions at LEP
The reactions e^+e^- -> e^+e^- Lambda X and e^+e^- -> e^+e^- Lambda X are
studied using data collected at LEP with the L3 detector at centre-of-mass
energies between 189 and 209 GeV. Inclusive differential cross sections are
measured as a function of the lambda transverse momentum, p_t, and
pseudo-rapidity, eta, in the ranges 0.4 GeV < p_t < 2.5 GeV and |\eta| < 1.2.
The data are compared to Monte Carlo predictions. The differential cross
section as a function of p_t is well described by an exponential of the form A
exp (- p_t / )$
Lambda and Sigma0 Pair Production in Two-Photon Collisions at LEP
Strange baryon pair production in two-photon collisions is studied with the
L3 detector at LEP. The analysis is based on data collected at e+e-
centre-of-mass energies from 91 GeV to 208 GeV, corresponding to an integrated
luminosity of 844 pb-1. The processes gamma gamma -> Lambda Anti-lambda and
gamma gamma -> Sigma0 Anti-sigma0 are identified. Their cross sections as a
function of the gamma gamma centre-of-mass energy are measured and results are
compared to predictions of the quark-diquark model
Proton-Antiproton Pair Production in Two-Photon Collisions at LEP
The reaction e^+e^- -> e^+e^- proton antiproton is studied with the L3
detector at LEP. The analysis is based on data collected at e^+e^-
center-of-mass energies from 183 GeV to 209 GeV, corresponding to an integrated
luminosity of 667 pb^-1. The gamma gamma -> proton antiproton differential
cross section is measured in the range of the two-photon center-of-mass energy
from 2.1 GeV to 4.5 GeV. The results are compared to the predictions of the
three-quark and quark-diquark models
Inclusive Charged Hadron Production in Two-Photon Collisions at LEP
Inclusive charged hadron production, e+e- -> e+e- h+- X, is studied using 414
pb-1 of data collected at LEP with the L3 detector at centre-of-mass energies
between 189 and 202 GeV. Single particle inclusive differential cross sections
are measured as a function of the particle transverse momentum, pt, and
pseudo-rapidity, eta. For p_t < 1.5 GeV, the data are well described by an
exponential, typical of soft hadronic processes. For higher pt, the onset of
perturbative QCD processes is observed. The pi+- production cross section for
pt > 5 GeV is much higher than the NLO QCD predictions
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