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41.
Lei Yu Cui Peng Amar Deep Regmi Virginia Murray Alessandro Pasuto Giacomo Titti Muhammad Shafique Tilak Priyadarshana D. G 《山地科学学报》2018,15(7):1383-1396
Belt and Road Initiative (BRI) is a Chinese national strategy which calls for cooperative economic, political and cultural exchange at the global level along the ancient Silk Road. The overwhelming natural hazards located along the belt and road bring great challenges to the success of BRI. In this framework, a 5-year international program was launched to address issues related to hazards assessment and disaster risk reduction (DRR). The first workshop of this program was held in Beijing with international experts from over 15 countries. Risk conditions on Belt and Road Countries (BRCs) have been shared and science and technology advancements on DRR have been disseminated during the workshop. Under this program, six task forces have been setup to carry out collaborative research works and three prioritized study areas have been established. This workshop announced the launching of this program which involved partners from different countries including Pakistan, Nepal, Russia, Italy, United Kingdom, Sri Lanka and Tajikistan. The program adopted the objectives of Sendai Framework for Disaster Risk Reduction 2015–2030 and United Nation Sustainable Development Goals 2030 and was implemented to assess disaster risk in BRCs and to propose suitable measures for disaster control which can be appropriate both for an individual country and for specific sites. This paper deals with the outcomes of the workshop and points out opportunities for the near future international cooperation on this matter. 相似文献
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43.
Bocchetti R Lamberti CV Pisanelli B Razzetti EM Maggi C Catalano B Sesta G Martuccio G Gabellini M Regoli F 《Marine environmental research》2008,66(1):24-26
This work investigated the natural variability of several biomarkers in Tapes philippinarum and Mytilus galloprovincialis, sampled from Northern Adriatic where these organisms are important sentinel species for future environmental impact assessment. Levels of metallothioneins, peroxisomal enzymes and acetylcholinesterase, showed a significant seasonality and marked differences between clams and mussels. Among antioxidant enzymes, catalase and GST decreased during the warmer period, the latter enzyme activity resulting particularly high in clams. The total oxyradical scavenging capacity toward peroxyl radicals decreased in mussels from winter to summer, indicating a prooxidant challenge due to higher seawater temperature and intensity of light irradiance. Lysosomal membrane stability did not exhibit significant seasonal variations, while some variations were observed for DNA damages. Overall results indicated a significant influence of seasonal variability on several biomarkers and species-specific differences which should be considered to discriminate the appearance of anthropogenic disturbance. 相似文献
44.
A branch of the South European Variscan chain is noticeably exposed in Sardinia. The early stage of collision between the Northern Gondwana margin and the Armorica Terrane Assemblage (ATA) generated syn-metamorphic folding and thrusting. The evidences of such deformation are well preserved in the nappe zone, a structural domain characterized by stacking of different tectonic units under metamorphism of Barrovian greenschist facies. A late, post-nappe, shortening, under retrograde metamorphic conditions, gave rise to wide, upright, N120–N160 trending antiforms that control the trend of the chain. The structural analysis of the Ozieri Metamorphic Complex (OMC) shows evidence of an important phase of late-Variscan extensional tectonics. Deformation results in, the formation of oppositely dipping, normal shear zones, which developed at upper and middle structural level along the limbs of major regional antiforms causing fabric reactivation, crustal thinning, and exhumation of the OMC core. Within the OMC, the activity of the shear zones was coeval with HT-LP metamorphism as suggests the occurrence of syn-kinematic cordierite + andalusite ± sillimanite + biotite. Whereas syntectonic dykes and a tonalite body in the deeper part of the OMC indicate that early emplacement of melt along shear zones and/or in the antiform hinges possibly supplied the heat for the anomalous thermal gradient and triggered the exhumation of a core complex-like structure. 相似文献
45.
46.
Luca Ciotti Giacomo Giampieri † 《Monthly notices of the Royal Astronomical Society》2007,376(3):1162-1168
We show how the complex-shift method developed by Appell to study the gravitational field of a point mass (and used in electrodynamics by, among others, Newman, Carter, Lynden-Bell, and Kaiser to determine some remarkable properties of the electromagnetic field of rotating charged configurations) can be extended to obtain new and explicit density–potential pairs for self-gravitating systems departing significantly from spherical symmetry. The rotational properties of two axisymmetric baroclinic gaseous configurations derived with the proposed method are illustrated. 相似文献
47.
Giacomo Giampieri 《Icarus》2004,167(1):228-230
A planetary body moving on an eccentric orbit around the primary is subject to a periodic perturbing potential, affecting its internal mass distribution. In a previous paper (Rappaport et al., 1997, Icarus 126, 313), we have calculated the periodic modulation of the gravity coefficients of degree 2, for a body on a synchronous orbit. Here, the previous analysis is extended by considering also non-synchronous orbits, and by properly accounting for the apparent motion of the primary due to the non uniform motion along the elliptical orbit. The cases of Titan and Mercury are briefly discussed. 相似文献
48.
Marco Bonini Giacomo Corti Chiara Del Ventisette Piero Manetti Genene Mulugeta Dimitrios Sokoutis 《地学学报》2007,19(5):360-366
Small‐scale analogue models were used to investigate the process of Cretaceous orthogonal extension in the West Antarctic Rift System. The models considered the transition from the East Antarctic Craton to a weaker lithosphere, and the results support previous hypotheses about the strong control exerted by lateral variations in lithospheric structures on the process of extension. Strain was mostly accommodated at the boundary between the two types of lithosphere, with a relative uplift of the cratonic block which remained essentially undeformed. Conversely, the weaker lithosphere showed wide‐rifting style geometry, locally associated with core complex‐like structures. In agreement with the natural prototype, this tectonic scenario led to a long‐lasting extension without continental break‐up, and to the absence of relevant surface magmatism. 相似文献
49.
Francesco Cavalcante Claudia Belviso Mario Bentivenga Saverio Fiore Giacomo Prosser 《Sedimentary Geology》2011,233(1-4):42-52
A mineralogical and geochemical study of clay lithologies and a biostratigraphic analysis of the carbonates from the deep-sea Lagonegro Basin (Southern Apennines—Italy) have been carried out to deduce in general the provenance of clay sediments and their paleoenvironmental conditions and particular to recognize the signature of the Paleocene–Eocene climatic global warming. The analysed succession comprising a wide stratigraphic interval of the Sannio Unit, spanning between Albian to the upper Oligocene–lower Miocene, is exposed near Accettura and Stigliano villages. Eighteen clay samples were analysed by XRD, XRF, SEM, TG-DTA. Their age was framed by biostratigraphic analyses carried out on carbonate sediments. Mineral assemblage of the clay sediments includes quartz, carbonates (calcite and dolomite), feldspars (plagioclase and k-feldspars), hematite, randomly illite/smectite mixed layers with a low illite percentage, kaolinite, discrete illite–muscovite, chlorite, palygorskite and sepiolite. The low illite percentage in randomly illite/smectite mixed layers indicates low diagenetic conditions for the studied successions. These features are unique for the Cretaceous–Tertiary successions of the Lagonegro domain and are particularly significant for the preservation of the native mineralogical assemblage useful to determine the provenance and paleoenvironmental conditions of the clayey sediments. Palygorskite and sepiolite are concentrated in the upper Paleocene–middle Eocene stratigraphic interval and particularly in the upper part of the early Eocene—lower part of the middle Eocene (biozone of Blow P 9–12). Clay sediments rich in palygorskite and sepiolite show a higher P2O5 amount and a lower kaolinite percentage, compatible with warm and arid climatic conditions typical of the global warming event well recorded in the southern tethyan margin. Likely palygorskite and sepiolite formed in lagoonal environment in nearby carbonate platform margins and then they were transported into the Lagonegro Basin as indicated by the well developed habitus of palygorskite. During the Paleogene the Lagonegro Basin and the nearby carbonate platforms represented a key sector the southern paleodomains of the Tethys. The discovery of these minerals gives a contribution to the reconstruction paleoenvironmental conditions of the Tethian paleo-margin during the early–middle Eocene. 相似文献
50.
Beatrice Cappelli Luigi Carmignani Francesca Castorina Anselmo Di Pisa Giacomo Oggiano Riccardo Petrini 《Geodinamica Acta》2013,26(1-2):101-118
AbstractThe Hereynian basement of Northern Sardinia consists of two main teetonometamorphic complexes : the Southern Paleozoic Low to Medium Grade Metamorphic Complex (LMGMC) and the Northern (Precaimbrian ?) High Grade Metamorphic Complex (HGMC). These complexes are separateli bu the “Posada-Asinara Line” which is a several kilometer-wide mylonitie belt consisting of micaschist. parag-neiss and quartzite that cuts across all Northern Sardinia and contains scattered hodies of amphibolites with granulile and eclogite facies relies.Major element composition of ampbibolites indicates they were derived from metamorphosed basalts of tholciitie affinity. REE and the relative abundances of HKS elements strongly suggest an oceanic basaltie prololith (N- and T-typc MORB). A whole-rock Sm-Nd isochron for the amphibolite protoliths yields an age of ea. 960 Ma.The Northern Sardinia basement can he interpreted as a continental collisional zone with the “Posada-Asinara Line” representing a suture zone squeezed between a crustal nappe (HGMC), which represents the overthrust continental margin. and (he inner portion of the Varisean orogenie wedge, which represents the underthrust continental margin with its Paleozoic cover (LMGMC).Geological and geochemical evidence indicate that the “Posada-Asinara Line” may he considered as part of the South European Hereynian Suture Zone. 相似文献