TY  - JOUR
A1  - Le Friant, A.
A1  - Ishizuka, O.
A1  - Boudon, G.
A1  - Palmer, M. R.
A1  - Talling, P. J.
A1  - Villemant, B.
A1  - Adachi, T.
A1  - Aljahdali, M.
A1  - Breitkreuz, C.
A1  - Brunet, M.
A1  - Caron, B.
A1  - Coussens, M.
A1  - Deplus, C.
A1  - Endo, D.
A1  - Feuillet, N.
A1  - Fraas, A. J.
A1  - Fujinawa, A.
A1  - Hart, M. B.
A1  - Hatfield, R. G.
A1  - Hornbach, M.
A1  - Jutzeler, M.
A1  - Kataoka, K. S.
A1  - Komorowski, J. -C.
A1  - Lebas, E.
A1  - Lafuerza, S.
A1  - Maeno, F.
A1  - Manga, M.
A1  - Martinez-Colon, M.
A1  - McCanta, M.
A1  - Morgan, S.
A1  - Saito, T.
A1  - Slagle, A.
A1  - Sparks, S.
A1  - Stinton, A.
A1  - Stroncik, Nicole
A1  - Subramanyam, K. S. V.
A1  - Tamura, Yui
A1  - Trofimovs, J.
A1  - Voight, B.
A1  - Wall-Palmer, D.
A1  - Wang, F.
A1  - Watt, S. F. L.
T1  - Submarine record of volcanic island construction and collapse in the Lesser Antilles arc: First scientific drilling of submarine volcanic island landslides by IODP Expedition 340
JF  - Geochemistry, geophysics, geosystems
N2  - IODP Expedition 340 successfully drilled a series of sites offshore Montserrat, Martinique and Dominica in the Lesser Antilles from March to April 2012. These are among the few drill sites gathered around volcanic islands, and the first scientific drilling of large and likely tsunamigenic volcanic island-arc landslide deposits. These cores provide evidence and tests of previous hypotheses for the composition and origin of those deposits. Sites U1394, U1399, and U1400 that penetrated landslide deposits recovered exclusively seafloor sediment, comprising mainly turbidites and hemipelagic deposits, and lacked debris avalanche deposits. This supports the concepts that i/ volcanic debris avalanches tend to stop at the slope break, and ii/ widespread and voluminous failures of preexisting low-gradient seafloor sediment can be triggered by initial emplacement of material from the volcano. Offshore Martinique (U1399 and 1400), the landslide deposits comprised blocks of parallel strata that were tilted or microfaulted, sometimes separated by intervals of homogenized sediment (intense shearing), while Site U1394 offshore Montserrat penetrated a flat-lying block of intact strata. The most likely mechanism for generating these large-scale seafloor sediment failures appears to be propagation of a decollement from proximal areas loaded and incised by a volcanic debris avalanche. These results have implications for the magnitude of tsunami generation. Under some conditions, volcanic island landslide deposits composed of mainly seafloor sediment will tend to form smaller magnitude tsunamis than equivalent volumes of subaerial block-rich mass flows rapidly entering water. Expedition 340 also successfully drilled sites to access the undisturbed record of eruption fallout layers intercalated with marine sediment which provide an outstanding high-resolution data set to analyze eruption and landslides cycles, improve understanding of magmatic evolution as well as offshore sedimentation processes.
KW  - landslide
KW  - volcanic island
KW  - debris avalanche
KW  - seafloor sediment failure
KW  - tsunami
KW  - IODP
Y1  - 2015
U6  - https://doi.org/10.1002/2014GC005652
SN  - 1525-2027
VL  - 16
IS  - 2
SP  - 420
EP  - 442
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Houlahan, Jeff E.
A1  - Currie, David J.
A1  - Cottenie, Karl
A1  - Cumming, Graeme S.
A1  - Ernest, S. K. Morgan
A1  - Findlay, C. Scott
A1  - Fuhlendorf, Samuel D.
A1  - Gaedke, Ursula
A1  - Legendre, Pierre
A1  - Magnuson, John J.
A1  - McArdle, Brian H.
A1  - Muldavin, Esteban H.
A1  - Noble, David
A1  - Russell, Robert
A1  - Stevens, Richard D.
A1  - Willis, Trevor J.
A1  - Woiwod, Ian P.
A1  - Wondzell, Steve M.
T1  - Compensatory dynamics are rare in natural ecological communities
N2  - In population ecology, there has been a fundamental controversy about the relative importance of competition- driven (density-dependent) population regulation vs. abiotic influences such as temperature and precipitation. The same issue arises at the community level; are population sizes driven primarily by changes in the abundances of cooccurring competitors (i.e., compensatory dynamics), or do most species have a common response to environmental factors? Competitive interactions have had a central place in ecological theory, dating back to Gleason, Volterra, Hutchison and MacArthur, and, more recently, Hubbell's influential unified neutral theory of biodiversity and biogeography. If competitive interactions are important in driving year-to-year fluctuations in abundance, then changes in the abundance of one species should generally be accompanied by compensatory changes in the abundances of others. Thus, one necessary consequence of strong compensatory forces is that, on average, species within communities will covary negatively. Here we use measures of community covariance to assess the prevalence of negative covariance in 41 natural communities comprising different taxa at a range of spatial scales. We found that species in natural communities tended to covary positively rather than negatively, the opposite of what would be expected if compensatory dynamics were important. These findings suggest that abiotic factors such as temperature and precipitation are more important than competitive interactions in driving year-to-year fluctuations in species abundance within communities.
Y1  - 2007
UR  - http://www.pnas.org/
U6  - https://doi.org/10.1073/pnas.0603798104
SN  - 0027-8424
ER  - 
TY  - JOUR
A1  - Unterhuber, Angelika
A1  - Povazay, B.
A1  - Bizheva, K.
A1  - Hermann, B.
A1  - Sattmann, Harald
A1  - Stingl, A.
A1  - Le, Trang
A1  - Seefeldt, Michael
A1  - Menzel, Ralf
A1  - Preusser, Matthias
A1  - Budka, Herbert
A1  - Schubert, Christian
A1  - Reitsamer, H.
A1  - Ahnelt, Peter Kurt
A1  - Morgan, J. E.
T1  - Advances in broad bandwidth light sources for ultrahigh resolution optical coherence tomography
N2  - Novel ultra-broad bandwidth light sources enabling unprecedented sub-2 pm axial resolution over the 400 nm-1700 nm wavelength range have been developed and evaluated with respect to their feasibility for clinical ultrahigh resolution optical coherence tomography (UHR OCT) applications. The state-of-the-art light sources described here include a compact Kerr lens mode locked Ti:sapphire laser (lambda(c) = 785 nm, Deltalambda = 260 nm, P-out = 50 mW) and different nonlinear fibre-based light sources with spectral bandwidths (at full width at half maximum) up to 350 nm at lambda(c) = 1130 nm and 470 nm at lambda(c) = 1375 run. In vitro UHR OCT imaging is demonstrated at multiple wavelengths in human cancer cells, animal ganglion cells as well as in neuropathologic and ophthalmic biopsies in order to compare and optimize UHR OCT image contrast, resolution and penetration depth
Y1  - 2004
SN  - 0031-9155
ER  -