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11.
Integrative taxonomic description of Plakina kanaky,a new polychromatic sponge species from New Caledonia (Porifera: Homoscleromorpha) 下载免费PDF全文
César Ruiz Julijana Ivanišević Pierre Chevaldonné Alexander V. Ereskovsky Nicole Boury‐Esnault Jean Vacelet Olivier P. Thomas Thierry Pérez 《Marine Ecology》2015,36(4):1129-1143
Four similar sponges of different colors, all unknown to science, were collected in submarine caves of New Caledonia. We aimed at determining whether the four chromotypes represented different species or phenotypic variations of a unique new species. We used an integrative taxonomic approach combining morphologic, molecular and metabolomic analyses. The main traits that define these specimens are a skeleton made of monolophose, trilophose and tetralophose calthrops only, high chemical diversity and a high abundance and diversity of prokaryotic symbionts. The symbiotic community includes two unique prokaryote morphotypes, which are described for the first time in Homoscleromorpha, and appeared to be vertically transmitted. Although several features slightly differ among chromotypes, the most parsimonious conclusion was to propose a single new species Plakina kanaky sp. nov. Our phylogenetic analysis indicated the paraphyly of the Plakina genus, with P. kanaky sp. nov. belonging to a clade that includes Plakina jani and Plakina trilopha. The present work demonstrates that integrative taxonomy should be used in order to revise the entire Plakinidae family and especially the non‐monophyletic genus Plakina. 相似文献
12.
Historical torrential flood events in the Kolubara river basin 总被引:1,自引:0,他引:1
13.
We study the seismic vulnerability of the interdependent European gas and electricity transmission networks from a topological point of view, whereby the electricity network depends on the gas network through gas‐fired power plants. First, we assessed the seismic response for each independent network; then we analyzed the increased vulnerability due to their interdependency. We implemented a probabilistic reliability model that encompasses the spatial distribution of both network structures and their seismic hazard exposure using a Geographic Information System. We characterized the network interdependency using the strength of coupling of the interconnections, together with the seismic response of the independent—gas—network. We calculated the network fragility curves of the independent and dependent networks in terms of various performance measures (connectivity loss, power loss, and impact on the population) and found that the gas network is more seismically vulnerable than the electricity network. The interdependency introduces an extra vulnerability to the electricity network response that decreases with the extensiveness of the networks' damage states. Damage was also evaluated at a local level in order to identify the most vulnerable parts of the network, where it was found that the potential for the highest power loss is located in southeast Europe. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
14.
Summary The paper presents the method of deriving representations, optimal from the point of view of global characteristics, for areal and extreme angular distortion (3), (7), if one is optional and the other characteristic is minimized at the same time. If a special minimization method (Section 5) is used for computer processing, the problem can be solved in the region of representation equations in the form of polynomials of the 3rd or 5th degree, while assuming symmetry relative to the equator and the central meridian. Thus, the method enables both the fundamental global characteristics to be regulated freely. Their dependence is illustrated in graphs (Figs 2 and 6) depending on the selected examples of representations of the whole globe. The latter shows that method is a contribution for cartographic practice as well. 相似文献
15.
Sea/land breeze climatological characteristics along the northern Croatian Adriatic coast 总被引:1,自引:0,他引:1
Summary Climatological characteristics along the northern Croatian Adriatic coast have been examined for nine meteorological stations
for the summertime sea/land breeze circulation. The stations considered are Pula-airport, Opatija, Rijeka, Senj, Malinska,
Rijeka-airport, Mali Lošinj, Rab and Zadar. The hourly surface measurements at each station from June to September for the
period 1991–2004 as well as the radiosoundings in Zadar (from 2002 to 2004) were used for the analysis. A dataset with the
sea/land breeze days was formed according to the several criteria.
The mean daily maxima of both air and sea surface temperatures were more influenced by the large scale disturbances toward
north (e.g. in Rijeka or Opatija) compared to the values for e.g. Zadar. Furthermore, the influence of the large scale disturbances
diminished toward the south concerning the sea–land temperature difference only at the stations placed at Rijeka Bay and Velebit
channel. The strongest sea breeze was found at Pula-airport and the most frequent ones at Opatija and Zadar. At Senj the rarest,
the weakest and the shortest sea breeze was observed. The climatological records of wind speed and air-sea temperature difference
(ΔT) showed for Opatija, Malinska and Zadar that the maximum measured wind speed is around 4.5 °C confirming the nonlinear relationship
between the sea breeze speeds and the ΔT during the day.
At most stations, the clockwise rotation of the hodographs prevails which is typical for the Northern hemisphere due to Coriolis
force, with the exception at Senj and Malinska. While the hodographs for Pula, Rijeka-airport and Mali Lošinj display a later
onset of the prevailing sea breeze because of the interaction among several sea breeze circulations, the results for Opatija,
Zadar and Senj show considerably distorted hodographs because of the nearby channeling of the air flow. 相似文献
16.
Acta Geotechnica - The experimental data dealing with the so-called small strain stiffness of soils are indispensable in developing and calibrating advanced numerical models. A literature review... 相似文献
17.
18.
Burša Milan Kouba Jan Müller Achim Raděj Karel True Scott A. Vatrt Viliam Vojtíšková Marie 《Studia Geophysica et Geodaetica》1999,43(1):1-6
Geopotential values W of the mean equipotential surfaces representing the mean ocean topography were computed on the basis of four years (1993 - 1996) TOPEX/POSEIDON altimeter data: W = 62 636 854.10m
2
s
–2
for the Pacific (P), W = 62 636 858.20m
2
s
–2
for the Atlantic (A), W = 62 636 856.28m
2s–2
for the Indian (I) Oceans. The corresponding mean separations between the ocean levels were obtained as follows: A – P = – 42 cm, I– P = – 22 cm, I – A = 20 cm, the rms errors came out at about 0.3 cm. No sea surface topography model was used in the solution. 相似文献
19.
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