171 research outputs found
Cronograma de execução das atividades agropecuárias e extrativistas, no Acre.
bitstream/CPAF-AC/1568/1/it16.pd
Applying the Disruption Index procedure to evaluate the urban seismic risk in the Mt. Etna area (Italy)
The Disruption Index is used here for the assessment of urban disruption in the Mt. Etna area
after a natural disaster. The first element of the procedure is the definition of the seismic input,
which is based on information about the historical seismicity and seismogenic faults. The second
element is the computation of the seismic impact on the building stock and infrastructure in the
region considered. Information on urban-scale vulnerability was collected and a geographic
information system was used to organize the data relating to buildings and network systems (e.
g., typologies, schools, strategic structures, lifelines). The central idea underlying the definition
of the Disruption Index is the identification and evaluation of the impacts on a target community,
considering the physical elements that contribute most to the severe disruption. The results of
this study are therefore very useful for earthquake preparedness planning and for the
development of strategies to minimize the risks from earthquakes. This study is a product of the
European “Urban Disaster Prevention Strategies using Macroseismic Fields and Fault Sources”
project (UPStrat-MAFA European project 2013).PublishedTorino, Italy3T. PericolositĂ sismica e contributo alla definizione del rischioope
Local energy decay of massive Dirac fields in the 5D Myers-Perry metric
We consider massive Dirac fields evolving in the exterior region of a
5-dimensional Myers-Perry black hole and study their propagation properties.
Our main result states that the local energy of such fields decays in a weak
sense at late times. We obtain this result in two steps: first, using the
separability of the Dirac equation, we prove the absence of a pure point
spectrum for the corresponding Dirac operator; second, using a new form of the
equation adapted to the local rotations of the black hole, we show by a Mourre
theory argument that the spectrum is absolutely continuous. This leads directly
to our main result.Comment: 40 page
Glossario de biotecnologia vegetal.
bitstream/item/107353/1/CNPH-GLOSS.-DE-BIOTEC.-VEG.-00.pd
Seasonality in bacterial diversity in north-west Mediterranean coastal waters: assessment through clone libraries, fingerprinting and FISH
We combined denaturing gradient gel electrophoresis (DGGE), catalysed reporter deposition-FISH (CARD-FISH) and clone libraries to investigate the seasonality of the bacterial assemblage composition in north-west Mediterranean coastal waters. DGGE analysis indicated that bacterial diversity changed gradually throughout the year, although with a clear distinction of the summer period. Alphaproteobacteria were the dominant group on an annual basis [29% of the DAPI (4′,6-diamidino-2-phenylindole) counts by CARD-FISH, and 70% of the bacterial clones]. The SAR11 clade was most abundant during spring and summer (>20% of DAPI counts), while the Roseobacter clade was abundant primarily in winter and spring (up to 7% of DAPI counts). The phylum Bacteroidetes constituted the second most important group and was quantitatively uniform throughout the year (average 11% of the DAPI counts). Gammaproteobacteria showed a peak during summer (8% of DAPI counts), when most of them belonged to the NOR5 cluster. Clone libraries and CARD-FISH showed reasonable agreement in the quantitative proportions of Bacteroidetes and Gammaproteobacteria, but Alphaproteobacteria were overrepresented in clone libraries. Sequencing of the most predominant DGGE bands failed to detect the SAR11 group despite their high abundance. The combination of the three molecular approaches allowed a comprehensive assessment of seasonal changes in bacterial diversit
On assessing importance of components in dysfunction urban systems given an earthquake: the case of Mt. Etna region
Mt Etna region (Sicily, Italy) is one of the test areas studied in the European Project “Urban
disaster Prevention Strategies using MAcroseismic fields and FAult sources” ( UPStrat-MAFA) to
which the methodology of Disruption Index (hereafter DI), recently developed to evaluate the
dysfunction of urban systems caused by earthquakes (Ferreira et al., 2014), has been applied on a trial
basis
Non-Structural Risk Evaluation: Experiences From Pilot Areas Of The Knowrisk Project
This paper presents a multidisciplinary approach to quantify seismic hazard and ground motion intensity parameters for non-structural seismic risk evaluation. In the framework of the European KnowRISK Project, three pilot areas were selected for testing different methodological approaches aimed at evaluating elements and measures to reduce seismic risk coming along with the failure of non-structural elements. At Mt. Etna, Italy, instrumental and historical macroseismic data are used to generate ground motion time series for different scenario events. Risk maps for non-structural damage are generated by using building vulnerability from census data and a damage model based on fragility curves; interstory drift spectra have been also calculated for a representative test site. In South Iceland, scenarios are defined basing on the June 2000 seismic sequence, which provided strong-motion data at several locations. The recorded data and other parameters of the source are used to perform finite-fault simulations of ground motion at different locations in the area and then to calculate interstory drift spectra. In Portugal a scenario referring to the Lower Tagus Valley was selected and finite-fault simulations for the nearby city of Lisbon were performed.PublishedThessaloniki, Greece5T. Sismologia, geofisica e geologia per l'ingegneria sismic
Warming and CO2 Enhance Arctic Heterotrophic Microbial Activity
Ocean acidification and warming are two main consequences of climate change that can directly affect biological and ecosystem processes in marine habitats. The Arctic Ocean is the region of the world experiencing climate change at the steepest rate compared with other latitudes. Since marine planktonic microorganisms play a key role in the biogeochemical cycles in the ocean it is crucial to simultaneously evaluate the effect of warming and increasing CO2 on marine microbial communities. In 20 L experimental microcosms filled with water from a high-Arctic fjord (Svalbard), we examined changes in phototrophic and heterotrophic microbial abundances and processes [bacterial production (BP) and mortality], and viral activity (lytic and lysogenic) in relation to warming and elevated CO2. The summer microbial plankton community living at 1.4°C in situ temperature, was exposed to increased CO2 concentrations (135–2,318 μatm) in three controlled temperature treatments (1, 6, and 10°C) at the UNIS installations in Longyearbyen (Svalbard), in summer 2010. Results showed that chlorophyll a concentration decreased at increasing temperatures, while BP significantly increased with pCO2 at 6 and 10°C. Lytic viral production was not affected by changes in pCO2 and temperature, while lysogeny increased significantly at increasing levels of pCO2, especially at 10°C (R2 = 0.858, p = 0.02). Moreover, protistan grazing rates showed a positive interaction between pCO2 and temperature. The averaged percentage of bacteria grazed per day was higher (19.56 ± 2.77% d-1) than the averaged percentage of lysed bacteria by virus (7.18 ± 1.50% d-1) for all treatments. Furthermore, the relationship among microbial abundances and processes showed that BP was significantly related to phototrophic pico/nanoflagellate abundance in the 1°C and the 6°C treatments, and BP triggered viral activity, mainly lysogeny at 6 and 10°C, while bacterial mortality rates was significantly related to bacterial abundances at 6°C. Consequently, our experimental results suggested that future increases in water temperature and pCO2 in Arctic waters will produce a decrease of phytoplankton biomass, enhancement of BP and changes in the carbon fluxes within the microbial food web. All these heterotrophic processes will contribute to weakening the CO2 sink capacity of the Arctic plankton community.En prens
Establishing nonlinearity thresholds with ultraintense X-ray pulses
X-ray techniques have evolved over decades to become highly refined tools for a broad range of investigations. Importantly, these approaches rely on X-ray measurements that depend linearly on the number of incident X-ray photons. The advent of X-ray free electron lasers (XFELs) is opening the ability to reach extremely high photon numbers within ultrashort X-ray pulse durations and is leading to a paradigm shift in our ability to explore nonlinear X-ray signals. However, the enormous increase in X-ray peak power is a double-edged sword with new and exciting methods being developed but at the same time well-established techniques proving unreliable. Consequently, accurate knowledge about the threshold for nonlinear X-ray signals is essential. Herein we report an X-ray spectroscopic study that reveals important details on the thresholds for nonlinear X-ray interactions. By varying both the incident X-ray intensity and photon energy, we establish the regimes at which the simplest nonlinear process, two-photon X-ray absorption (TPA), can be observed. From these measurements we can extract the probability of this process as a function of photon energy and confirm both the nature and sub-femtosecond lifetime of the virtual intermediate electronic state
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