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41.
David McEntire Jill Souza Matthew Lloyd Collins Ekong J. Peters Abdul-Akeem Sadiq 《Natural Hazards》2012,61(3):1389-1409
This paper underscores the importance of damage assessment and recognizes the direct effect it has on post-disaster response
and recovery operations. The paper first explores the literature on this subject, including the history, types, methods, and
problems relating to damage assessment. After discussing the employed research methodology, the paper uses the Paso Robles
(San Simeon, California) earthquake as a case study to illustrate the challenges and successes with regard to damage assessment.
Logistics, politics, information management, coordination, preparedness, and other topics are discussed in this section. The
paper concludes with lessons and opportunities for research and its application. 相似文献
42.
The Huwan Shear Zone (HSZ) is an eclogite bearing transpressive wrench zone located along the Shangdan Suture that juxtaposes the Paleozoic Qinling and Mesozoic Hong'an–Dabie orogenic terrains. The region preserves a complex history that bridges the gap between adjacent orogenic terrains. Simultaneous in-situ trace element, U–Th–Pb and Lu–Hf‐isotope analysis of zircon grains from samples of the Xiongdian and Sujiahe eclogite identify a late Carboniferous to early Permian period of high pressure metamorphism, ca. 283 to 306 Ma. Zircon grains are observed to respond to metamorphic overprint via a two stage process: (1) An initial prograde stage of fluid catalyzed interface coupled dissolution–reprecipitation, involving exsolution of a non-ideal solid solution thorite (ThSiO4) end member and loss of highly incompatible components (LREE and Pb), (2) A second stage of coupled zircon dissolution, coarsening, and new rim growth in equilibrium with garnet at high pressure conditions.We identify Proterozoic whole rock Sm–Nd and zircon grain Lu–Hf isotopic evidence which challenges the traditional interpretation that the Xiongdian and Sujiahe eclogite formed in response to early Paleozoic mantle melting and oceanic crust generation. We argue the Huwan Shear Zone contains no conclusive evidence of early/middle Paleozoic oceanic crust, but rather Proterozoic crustal components analogous to those found in the Northern Qinling Terrain and associated with formation of the Shangdan Suture. We present a simpler geodynamic model involving continuous convergence and accretion of terrains onto the southern margin of the North China Block during the Paleozoic Qinling and Mesozoic Dabie orogenies. 相似文献
43.
A. Papafotiou R. Helmig J. Schaap P. Lehmann A. Kaestner H. Flühler I. Neuweiler R. Hassanein B. Ahrenholz J. Tölke A. Peters W. Durner 《Advances in water resources》2008
A well-controlled 3-D experiment with pre-defined block heterogeneities is conducted, where neutron tomography is used to map 3-D water distribution after two successive drainage steps. The material and hydraulic properties of the two sands are first measured in the laboratory with multistep outflow experiments. Additionally, the pore structure of the sands is acquired by means of image analysis of synchrotron tomography data and the structure is used for pore-scale simulation of one- and two-phase flow with Lattice-Boltzmann methods. This gives us another set of material and hydraulic parameters of the sands. The two sets of hydraulic properties (from the lab scale and from the pore scale) are then used in numerical simulations of the 3-D experiment. 相似文献
44.
J P Shaw A T Large J K Chipman D R Livingstone L D Peters 《Marine environmental research》2000,50(1-5):405-409
Mytilus edulis digestive gland microsomes were prepared from indigenous populations sampled from a clean reference site (Port Quin) and an urban-industrial contaminated site (Blackpool) in the UK. Samples were collected in March/April, May, August and December 1998. Western blot analysis was performed using polyclonal antibodies to fish CYP1A and rat CYP2E using partially purified M. edulis CYP as a positive control, to aid identification. CYP1A- and CYP2E-immunopositive protein levels showed different site-specific seasonal variation with higher levels of CYP2E determined in May (P < 0.05). At both sites, lower levels of CYP1A-immunopositive protein but not CYP2E-immunopositive protein were observed in the samples collected in December (P < 0.05). This correlated with lower levels of nuclear DNA damage (Comet assay expressed as per cent tail DNA) observed in December compared to August (P < 0.05). 相似文献
45.
Summary The composite method and an atmospheric moisture budget is applied to study the present synoptic summer situation in the West African Sahel. This allows the information of the synoptic scale flow systems at the last glacial maximum to be obtained. Relying on the results of general circulation models and of local geological findings the palaeosynoptic situation was found to consist of the same constituents as today's given pattern. In both time slices the strength of the midtropospheric African Easterly Jet determines the intensity and frequency of the Sahelian synoptic disturbances: the Easterly Waves and the Squall Lines. The glacial rainfall intensity of the Squall Lines, the most effective rain-bearing system of the Sahel, is calculated to be 2/3 of the modern one. Additionally, only half the number of Squall Lines propagated across the West African continent per summer month. Thus the glacial rainfall amount of the Sahel was roughly 30% of the value observed today.With 6 Figures 相似文献
46.
47.
Lars Frlin David R. Livingstone Kerstin Magnusson Laurence D. Peters Montserrat Sol Anders Sjlin ke Granmo 《Marine environmental research》1996,42(1-4)
The use of a suite of different biochemical markers in the deep sea fish Roundnose grenadier and caged common mussels, and analyses of contaminant levels in the mussels, indicate that Skagerrak are more polluted than waters around the Faroe Islands. In Roundnose, induction of ethoxyresorufin-O-deethylase (EROD) is consistent with increased benzo(a)pyrene hydroxylase (BPH) in mussels and elevated levels of polynuclear aromatic hydrocarbons (PAHs) in mussels and sediment from Skagerrak. This evidence of a large-scale environmental impact of pollutants should lead to further efforts to decrease transport into, and deposition of, waste compounds in the Skagerrak area. 相似文献
48.
Using the half-cycle analysis method, a comparison is made between extreme events in half-hour intervals of hurricane Camille wave data and extreme events in synthesized Gaussian realizations having the same variance spectra as the measured data. While various statistical comparisons of measured and simulated Gaussian data reveal a consistent trend toward Gaussian behavior for the majority of wave events in the hurricane generated data, it is shown using the half-cycle analysis method that the more extreme wave events occurring near the height of the storm were distinctly non-Gaussian. 相似文献
49.
Shaw JP Large AT Livingstone DR Doyotte A Renger J Chipman JK Peters LD 《Marine environmental research》2002,54(3-5):505-509
Mytilus edulis were collected from a reference site (Port Quin) and an urban/industrial contaminated site (New Brighton) in the UK during June 1999. Levels of PCBs (sigma7 congeners) and CB-138 were determined to be, respectively, 21 fold and 16 fold higher in the mussel digestive glands from New Brighton. Levels of CYPIA-immunopositive protein were 1.5 fold higher (P < 0.05) at the polluted site but the levels of DNA strand breaks were 1.3 fold higher (P<0.05) at the reference site. Mussels from Port Quin were placed in cages at both sites and both transplanted and indigenous populations sampled in September (13 weeks). Mussels transplanted from the reference site to the industrial site, reported elevated levels of CYP1A-immunopositive protein (1.4 fold; P < 0.05) and higher levels of DNA damage (1.2 fold; P < 0.05) compared to caged populations at the reference site and a PCB loading similar to the populations from the polluted site. Moreover, transplanted mussels had DNA damage 1.8 fold greater (P < 0.05) than indigenous mussels at the transplant site. These changes were small but significant when compared to the observed temporal changes in the indigenous populations. 相似文献
50.
Blue mussels (Mytilus edulis, L.) were exposed to a single dose of 1 ppb benzo[a]pyrene (BaP) under subtidal (SC) or tidal conditions (TC; 6 h immersion, 6 h emersion) in order to follow its bioaccumulation in whole mussel and mantle tissue, and to compare BaP-mediated toxicity on lipids (malonaldehyde formation, MDA) in the mantle. Rapid uptake of BaP (70-80% of BaP initially introduced in tanks) was observed in both conditions after 12 h, but subsequent depuration in clean water was slower in TC mussels. BaP levels decreased in whole tissue in both conditions between 12 and 24 h, but increased in mantle. The mantle BaP levels were similar during the first 4 days in SC and TC, but whereas they decreased in SC after 7 days. BaP was retained at high levels in mantle in TC until the end of the study (14 days). In both conditions, significant increases (P < 0.05) in lipid peroxidation were observed after 4 days, but MDA levels were approximately 3 times higher in the mantle of TC than SC mussels, although BaP tissue concentrations were similar. These observations suggested that increased BaP-mediated toxicity in mantle lipid was due to the interactive effect of the tidal cycle of immersion/emersion on BaP-mediated oxidative damage. 相似文献