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51.
A biomarker study was undertaken using the Calico scallop Argopecten gibbus to assess the ecotoxicological effects of a semi-submerged municipal dump on the adjacent patch reef lagoon ecosystem (Castle harbour, Bermuda). Caged scallops were deployed in situ for 2 months at various distances from the dump (50 m, 900 m and 2.7 km) and at a reference site (14 km). A suite of biomarkers comprising metallothionein (MT), lipid peroxidation (LPO), vitellin-like proteins (Vn), glutathione S-transferase (GST), DNA strand breaks and condition factor (CF) were investigated in various tissues of the scallop (gill, digestive gland and gonad). Levels of heavy metals were also measured in the whole scallop soft tissue. While there was some variation in response between tissues, in general the results indicated that the dump was negatively impacting scallops deployed in the adjacent marine environment: elevated levels of MT, DNA strand breaks, Vn and GST and reduced condition factor were found for scallops deployed nearest to the dump and at the site 1.5 km from this point source of contamination (Tuckers town) in Castle harbour, with respect to the reference site, North Rock (although this exhibited some degree of metal contamination). The gills from scallops deployed at the dump site were the most responsive tissue, with the highest expression of MT, LPO and DNA damage. This study indicates the potential of the Calico scallop as a convenient bioindicator species in the marine tropical benthos. 相似文献
52.
53.
Statistical modelling of Europe-wide landslide
susceptibility using limited landslide inventory data 总被引:2,自引:0,他引:2
M. Van Den Eeckhaut J. Hervás C. Jaedicke J.-P. Malet L. Montanarella F. Nadim 《Landslides》2012,9(3):357-369
In many regions, the absence of a landslide inventory hampers the production of susceptibility or hazard maps. Therefore, a method combining a procedure for sampling of landslide-affected and landslide-free grid cells from a limited landslide inventory and logistic regression modelling was tested for susceptibility mapping of slide- and flow-type landslides on a European scale. Landslide inventories were available for Norway, Campania (Italy), and the Barcelonnette Basin (France), and from each inventory, a random subsample was extracted. In addition, a landslide dataset was produced from the analysis of Google Earth images in combination with the extraction of landslide locations reported in scientific publications. Attention was paid to have a representative distribution of landslides over Europe. In total, the landslide-affected sample contained 1,340 landslides. Then a procedure to select landslide-free grid cells was designed taking account of the incompleteness of the landslide inventory and the high proportion of flat areas in Europe. Using stepwise logistic regression, a model including slope gradient, standard deviation of slope gradient, lithology, soil, and land cover type was calibrated. The classified susceptibility map produced from the model was then validated by visual comparison with national landslide inventory or susceptibility maps available from literature. A quantitative validation was only possible for Norway, Spain, and two regions in Italy. The first results are promising and suggest that, with regard to preparedness for and response to landslide disasters, the method can be used for urgently required landslide susceptibility mapping in regions where currently only sparse landslide inventory data are available. 相似文献
54.
Abstract In the long term, the Kyoto Protocol will be insufficient to stabilize the greenhouse gas (GHG) concentrations in the atmosphere; quantified commitments will also be essential for major developing countries (and the US). International cooperation mechanisms, such as permit trading systems, can help achieve global economic efficiency. However, the initial allocation of emission permits raises many debates on equity. The main objective is to propose a decision aid tool for decision makers, which is capable of providing relevant information on various equitable permit allocation schemes and burden sharing. A dynamic multicriteria model is proposed to share the global quantity of permits among 15 regions, taking into account multiple definitions of equity and regional interests. The World-MARKAL energy model is used to compute the gross reduction cost (before permit exchanges) for each region. Afterward, it is possible to calculate their net reduction costs (after permit exchanges) according to different allocation schemes. A realistic simulation of the tool provides examples of results, i.e. ranges of permit allocations and net costs for each region. Finally, some recommendations are proposed to policy makers to design a decision process adapted to the global context of negotiations. 相似文献
55.
Cold Dust and Very Cold Excess Emission in the Galaxy 总被引:2,自引:0,他引:2
Hervé Bourdin Françcois Boulanger Jean-Philippe Bernard Guilaine Lagache 《Astrophysics and Space Science》2002,281(1-2):243-246
We provide insight in the origin of the far-IR to mm emission from galaxies by presenting a decomposition of the Galaxy emission
where we separate the contributions from dust in the atomic gas and dust associated with quiescent molecular gas as a function
of Galacto-centric distance. This decomposition leaves a puzzling very cold emission excess with a brightness independent of Galactic longitude that might be pointing at interstellar matter in the
outer Galaxy not traced by H I nor CO emission.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
56.
57.
Yunzhao Wu Sebastien Besse Jian-Yang Li Jean-Philippe Combe Zhenchao Wang Xianfeng Zhou Chao Wang 《Icarus》2013,222(1):283-295
The main objective of this study is to develop a new photometric correction that is suitable for global Chang’ E-1 (CE-1) Interference Imaging Spectrometer (IIM) data. We considered two improvements in the accuracy of the photometric correction: (1) classifying the whole Moon’s surface into four classes (very bright rays, mature highlands, low FeO basalts, and high FeO basalts) based on the FeO contents; (2) decoupling the combined effects of the solar photometry and the detector responsivity along the cross-track. The results showed that our decoupling method could correct the non-uniformity of detector response but retain the cross-track photometry. Based on these in-flight calibrated data, spectrally continuous photometric functions of the four classes were obtained. By eliminating the contamination from highlands ejecta and low FeO basalts, the opposition surge of the high FeO maria was evident for the first time. The amplitude and width of the opposition surge presents wavelength dependence, which suggests that shadow hiding is the mechanism responsible for the opposition surge. A global lunar reflectance map whose boundaries between adjacent orbits are invisible was generated using the new four-type photometric functions. The quality of the global mosaic and the consistency of the reflectance spectra of the same area obtained in different orbits indicate the effectiveness of our photometric correction method. Although our method was specifically applied to the IIM data, the photometric correction method and the parameter values derived in this study is expected to be suitable for other optical instruments. 相似文献
58.
The present investigation aims at identifying the needs of the Argentinean agro-business sector for climate research and information. Our approach is focused on any type of climate information from past observations to seasonal prediction and climate change projections. We tried, in particular, to evaluate the possible existence of specific research themes that would be of major interest for these agriculture end-users. We interviewed representatives of seventeen companies from three major agrobusiness sectors: (1) regional/national entities such as agricultural associations, cooperatives and commercial trade boards; (2) insurance companies in the Argentinean agro-insurance market; and (3) large national and international companies representing cereal producers, agro-chemistry and agro-seeds. While all the interviewees recognized the strong influence of climate on their activities, they all pointed out that, at the time of making decision, they considered the political and economic risks rather than the climate one. In many aspects, climate is often considered as a fatality against which it is difficult to be protected. An interesting result is the confidence of the private sectors in the climate information provided by public sources (INTA, SMN, Universities) although they contract private consultants for frequent reports and tendencies. Finally, we explain how such sectors could make a better use of climate information (seasonal prediction, climate change scenarios) that could be integrated in their business projections. In particular, the development of new financial contracts (climate derivatives) open in countries with a relatively poor insurance history new ways to protect the different agricultural sectors, from the producer to large companies. 相似文献
59.
The flow of a magma into a dike, sill, laccolite, pipe or batholith leads to a preferential orientation of crystals in the magma. A study by computer simulation has brought to light certain types of fabric for oblate and prolate minerals in the case of a plane deformation, on the one hand by pure shear, and on the other hand by simple shear. Theoretical and practical studies suggest a new method for determining the direction of injection (“injection axis”) in a dike, based on the angular relations of minerals near the walls.New developments are proposed on the relations between plane and linear flow-lines, on the distinction between “apparent flow-lines” and the transport-plane of the magma (“real flow-lines”) and on the amount of magma deformation.
Résumé
La mise en place d'un magma dans une caisse filonienne (ou dans des sills, dykes, laccolites, batholites, etc.) s'accompagne d'une orientation préférentielle des minéraux déjà formés. Une étude par simulation sur ordinateur a mis en évidence certains types de fabrique pour les minéraux phylliteux et les minéraux aciculaires dans le cas d'une déformation plane, d'une part par aplatissement pur et d'autre part, par cisaillement simple.En application théorique puis pratique, un nouveau critère de sens de mise en place (axe d'injection) dans une caisse filonienne est défini: le pincement des minéraux aux épontes; en effet, à chacune d'elles, les fluidalités apparentes, observées sur les minéraux, font un angle avec la paroi du filon.Des développements nouveaux sont proposés concernant les relations entre fluidalités planaire et linéaire, la distinction entre fluidalité apparente et plan de transport du magma (fluidalité réelle), le taux de déformation subi par le magma,.... 相似文献60.
Detecting decadal changes in ENSO using neural networks 总被引:1,自引:2,他引:1
Julie A. Leloup Zouhair Lachkar Jean-Philippe Boulanger Sylvie Thiria 《Climate Dynamics》2007,28(2-3):147-162