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11.
The risk evaluation model CAPRA (Comprehensive Approach to Probabilistic Risk Assessment) is a techno-scientific methodology and information platform, composed of tools for evaluating and communicating risk at various territorial levels. The model allows evaluating losses on exposed elements using probabilistic metrics, such as the loss exceedance curve, the expected annual loss and the probable maximum loss, useful for multi-hazard risk analyses. In this article, the process of probabilistic seismic risk analysis is described, explaining the main features of the CAPRA modules of hazard, vulnerability and risk estimation applied to the city of Barcelona, Spain. In addition, according to the physical risk results and the information on the socioeconomic indicators of the city, this article presents the holistic evaluation of seismic risk, which is a valuable result to facilitate the integrated risk management by the different stakeholders involved in risk reduction decision making.  相似文献   
12.
Marine Stewardship Council (MSC) certification is a market-based incentive program recognizing well-managed fisheries. Currently, four Argentine fisheries are involved in the MSC program. Using in-depth, semi-structured interviews with fishery stakeholders, the study surveys their perceptions regarding MSC certification. MSC certification is positively perceived because stakeholders focus on knowledge of the process. Most respondents consider certification as encouraging effective fishery stakeholders’ participation: access to information, increased communication, and reaching consensus. Market/political/social realities will prove whether a more intense participation of Argentine fisheries in the certification initiative is useful. Because some markets in the EU and USA are demanding MSC certified products, there is a need to work towards a governance structure that helps link certification with policy market outcomes to ensure exportation of Argentine fish. MSC certification may suggest improved management of participatory bottom-up planning. This bottom-up approach provides an opportunity to establish feedback mechanisms and organizational changes.  相似文献   
13.
Riassunto Vengono esposti e discussi i risultati di alcune misure della suscetività magnetica di minerali magnetitiferi italiani. Fra l'altro si dimostra l'impossibilità di una legge generale di interdipendenza fra i valori della suscettività ed il carattere genetico dei giacimenti, indicando nuovi orientamenti per approfondire con successo simili indagini.
Summary The results of some measures of magnetic susceptibility of italian magnetic ores are reported and discussed. It is proved the impossibility of a general relation between the magnitude of the susceptibility and the genetic character of the ores; however, new views are pointed out to successfully deepen the results.

Zusammenfassung Die Ergebnisse einiger Suszeptibilit?ts-Messungen von ital. Magnetit-Mineralien verschiedener Genesis werden angegeben und erl?utert. U. a. beweist man, dass ein allgemeine Gesetz für eine einfache Zusammenhang zwischen den Werte der Suszeptibilit?t und die genetischen Eigentümlichkeiten der Lagerst?tten nicht bestehen kann. Neue Forschungsrichtungen dafür werden vorgeschlagen.
  相似文献   
14.
La Nota I venne pubblicata a pag. 286 e seg. del Vol. XII (Fasc. 5–6), 1948, di questa Rivista. Le numerazioni delle citazioni bibliografiche e delle formole fanno seguito a quelle usate nella Nota I.  相似文献   
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Human impact on adjacent coastal waters, leading to alteration in nutritional environment and hence affecting phytoplankton biomass (Chlorophyll a), will probably be enhanced by the nearby presence of ports. The main goal of this study is to assess the influence of nearby presence of port on phytoplankton biomass build-up and the physical–chemical environmental characteristics in two contrasting coastal systems (Otaru port, S-IN and an exposed coastal area, S-OUT) in the western Hokkaido coast off Otaru port, Japan. Sampling was conducted on “bi-weekly and monthly” basis during the period of September 2006–December 2007 and data comprising 11 pelagic variables were obtained. In most instance, phytoplankton biomass, nutrients' (NH4, NO3, PO4, and Si(OH)4) concentrations and nutrients' molar ratios were higher at the Otaru port location. Physical parameters (temperature, salinity, hydrogen ion concentration (pH), photosynthetically active radiation (PAR) and dissolved oxygen, (DO)) were not significantly different (P > 0.05) between the two locations. With the exception of salinity, pH and DIC, all variables measured showed significant variation (P < 0.05) with season. While the coefficient of variation (CV) of physical parameters and phytoplankton biomass were relatively higher in Otaru port location (S-IN), the exposed coastal location (S-OUT) showed a higher variation in chemical parameters. Other variables showed different patterns between the two locations. We conclude that ports, due to its activities and restricted circulation favour high nutrient loading and phytoplankton biomass build-up in adjacent coastal systems, thus, suggesting the need for continuous field observation data in order to advance our knowledge on possible future human impact on coastal environment and the need to monitor and control port activities.  相似文献   
17.
Many deep-sea animals derive part of their nutrition from rare and unpredictable food falls. However, traits that allow organisms inhabiting the sea floor to exploit carrion are poorly understood. We found in laboratory experiments that hagfish (Eptatretus stouti), gastropods (Neptunea amianta) and amphipods (Orchomene obtusus) survived extended periods of starvation, in some cases for more than a year. When exposed to odors emitted from carrion, most individuals of E. stouti and O. obtusus began searching for food within seconds, whereas none responded to the scent of the live prey. In contrast, the slow crawling N. amianta readily consumed carrion but showed no apparent response to any odor solutions tested. Because more motile animals exhibited lower thresholds for response to signal molecules, sensitivity to chemical cues appears related to species mobility. Hagfish were also found to defend carrion from some competitors by releasing slime when feeding. Though varying dramatically in size, morphology, locomotive ability, and phylogeny, these three species all possess traits well suited for a scavenging lifestyle.  相似文献   
18.
This work is devoted to the analysis of the variation of albedo measured by orbiting instruments with atmospheric opacity on Mars. The study has been conduced by analysing Mars Global Surveyor Thermal Emission Spectrometer (MGS-TES) data from martian regions with different surface albedo.In support of these data, synthetic spectra with different surface albedo and atmospheric opacities have been computed, so that a comparison has been performed. The synthetic spectra have been retrieved by using two different grain sizes for suspended dust (0.5 and 1.2 μm), allowing a comparison between the two models and the observations.Using the DCI, a parameter describing the quantity of dust deposited on the surface, the effectiveness of the single scattering approximation has been tested for low atmospheric opacity by analysing the quality of the linear fit up to different atmospheric opacity.For more opaque conditions two kinds of fits have been applied to the data, linear and second-order degree polynomial. In this case, we found that the polynomial fit better describes the observations.The analysis of these data made it possible to notice a peculiar trend, already reported by Christensen (1988), of the albedo over Syrtis Major after the occurrence of dust storms, but, differently from that work, now the study of DCI together with atmospheric opacity and albedo allowed us to robustly confirm the hypothesis made by Christensen.Finally, the comparison between observations and synthetic spectra computed with models with different particles grain sizes indicates that dust particles of 0.5 μm diameter are the most effective to change the aerosol atmospheric opacity on Mars.  相似文献   
19.
The Square Kilometre Array (SKA) will have a low frequency component (SKA-low) which has as one of its main science goals the study of the redshifted 21 cm line from the earliest phases of star and galaxy formation in the Universe. This 21 cm signal provides a new and unique window both on the time of the formation of the first stars and accreting black holes and the subsequent period of substantial ionization of the intergalactic medium. The signal will teach us fundamental new things about the earliest phases of structure formation, cosmology and even has the potential to lead to the discovery of new physical phenomena. Here we present a white paper with an overview of the science questions that SKA-low can address, how we plan to tackle these questions and what this implies for the basic design of the telescope.  相似文献   
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