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Herv Thbault Alessia M. Rodriguez y Baena Bruno Andral Delko Barisic Jos Benedicto Albaladejo Alexandru S. Bologa Redouane Boudjenoun Roberta Delfanti Victor N. Egorov Tahar El Khoukhi Heleni Florou Goran Kniewald Abdelkader Noureddine Vasile Patrascu Mai Khanh Pham Alfonso Scarpato Nikolay A. Stokozov Sayhan Topcuoglu Michel Warnau 《Marine pollution bulletin》2008,57(6-12):801
The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1 Bq kg−1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. 相似文献
33.
Vasile Mioc Mira-Cristiana Anisiu Michael Barbosu 《Celestial Mechanics and Dynamical Astronomy》2005,91(3-4):269-285
Studying the two-body problem associated to an anisotropic Schwarzschild-type field, Mioc et al. (2003) did not succeed in
proving the existence or non-existence of periodic orbits. Here we answer this question in the affirmative. To do this, we
start from two basic facts: (1) the potential generates a strong force in Gordon’s sense; (2) the vector field of the problem
exhibits the symmetries S
i
,
, which form, along with the identity, an Abelian group of order 8 with three generators of order 2. Resorting to S
2 and S
3, in connection with variational methods (particularly the classical lower-semicontinuity method), we prove the existence
of infinitely many S
2- or S
3-symmetric periodic solutions. The symmetries S
2 and S
3 constitute an indicator of the robustness of the classical isotropic Schwarzschild-type system to perturbations (as the anisotropy
may be considered). 相似文献