128 research outputs found
Radial interpolation of GPS and leveling data of ground deformation in a resurgent caldera: application to Campi Flegrei (Italy)
This study presents a new method, called the Radial Interpolation Method, to interpolate data characterized by an approximately radial pattern around a relatively constrained central zone, such as the ground deformation patterns shown in many active volcanic areas. The method enables the fast production of short-term deformation maps on the base of spatially sparse ground deformation measurements and can provide uncertainty quantification on the interpolated values, fundamental for hazard assessment purposes and deformation source reconstruction. The presented approach is not dependent on a priori assumptions about the geometry, location and physical properties of the source, except for the requirement of a locally radial pattern, i.e., allowing multiple centers of symmetry. We test the new method on a synthetic point source example, and then, we apply the method to selected time intervals of real geodetic data collected at the Campi Flegrei caldera during the last 39 years, including examples of leveling, Geodetic Precise Traversing measurements and Global Positioning System. The maps of horizontal displacement, calculated inland, show maximum values lying along a semicircular annular region with a radius of about 2–3 km in size. This semi-annular area is marked by mesoscale structures such as faults, sand dikes and fractures. The maps of vertical displacement describe a linear relation between the maximum vertical uplift measured and the volume variation. The multiplicative factor in the linear relation is about 0.3 × 106 m3/cm if we estimate the proportion of the ΔV that is captured by the GPS network onland and we use this to estimate the full ΔV. In this case, the 95% confidence interval on K because of linear regression is ± 5%. Finally, we briefly discuss how the new method could be used for the production of short-term vent opening maps on the base of real-time geodetic measurements of the horizontal and vertical displacements
Photosynthetic antenna size in higher plants is controlled by the plastoquinone redox state at the post-transcriptional rather than transcriptional level.
We analyze the effect of the plastoquinone redox state on the regulation of the light-harvesting antenna size at transcriptional and post-transcriptional levels. This was approached by studying transcription and accumulation of light-harvesting complexes in wild type versus the barley mutant viridis zb63, which is depleted in photosystem I and where plastoquinone is constitutively reduced. We show that the mRNA level of genes encoding antenna proteins is almost unaffected in the mutant; this stability of messenger level is not a peculiarity of antenna-encoding genes, but it extends to all photosynthesis-related genes. In contrast, analysis of protein accumulation by two-dimensional PAGE shows that the mutant undergoes strong reduction of its antenna size, with individual gene products having different levels of accumulation. We conclude that the plastoquinone redox state plays an important role in the long term regulation of chloroplast protein expression. However, its modulation is active at the post-transcriptional rather than transcriptional level
Metabolomic patterns associated to QTc interval in shiftworkers: an explorative analysis
Objectives: 1H NMR-metabolomic approach was used to investigate QTc interval correlation with plasma metabolic profiles in shiftworkers. Methods: Socio-demographic data, electrocardiographic QTc interval and plasma metabolic profiles from 32 male shiftworkers, were correlated by multivariate regression analysis. Results: We found a positive correlation between QTc interval values, body mass index, glycemia and lactate level and a negative correlation between QTc interval and both pyroglutamate and 3-hydroxybutyrate plasma level. Conclusions: Our analysis provides evidence of the association between clinical, metabolic profiles and QTc interval values. This could be used to identify markers of early effects and/or susceptibility in shiftworker
The effects of vent location, event scale and time forecasts on pyroclastic density current hazard maps at Campi Flegrei caldera (Italy)
This study presents a new method for producing long-term hazard maps for pyroclastic
density currents (PDC) originating at Campi Flegrei caldera. Such method is based on
a doubly stochastic approach and is able to combine the uncertainty assessments on
the spatial location of the volcanic vent, the size of the flow and the expected time of
such an event. The results are obtained by using a Monte Carlo approach and adopting
a simplified invasion model based on the box model integral approximation. Temporal
assessments are modeled through a Cox-type process including self-excitement effects,
based on the eruptive record of the last 15 kyr.Mean and percentilemaps of PDC invasion
probability are produced, exploring their sensitivity to some sources of uncertainty and to
the effects of the dependence between PDC scales and the caldera sector where they
originated. Conditional maps representative of PDC originating inside limited zones of the
caldera, or of PDC with a limited range of scales are also produced. Finally, the effect of
assuming different time windows for the hazard estimates is explored, also including the
potential occurrence of a sequence of multiple events. Assuming that the last eruption
of Monte Nuovo (A.D. 1538) marked the beginning of a new epoch of activity similar to
the previous ones, results of the statistical analysis indicate a mean probability of PDC
invasion above 5% in the next 50 years on almost the entire caldera (with a probability
peak of 25% in the central part of the caldera). In contrast, probability values reduce
by a factor of about 3 if the entire eruptive record is considered over the last 15 kyr, i.e.,
including both eruptive epochs and quiescent periods
The late MIS 5 Mediterranean tephra markers: A reappraisal from peninsular Italy terrestrial records
We present new tephrostratigraphic records from the late MIS 5 (ca 110e80 ka) terrestrial sediments
from southern and central Italy. On the one hand, the central Italy record consists of an outcropping
lacustrine sequence from the Sulmona intermountain basin that contains four trachyticephonolitic
tephra layers (POP3, POP2a, POP2b, POP1), all of which show a K-alkaline affinity that is typical for
the Roman co-magmatic Province. The POP3 and POP1 layers were dated by 40Ar/39Ar method at
106.2 1.3 ka (2s) and 92.4 4.6 ka (2s), respectively. The sequence in southern Italy, on the other
hand, is represented by post-Tyrrhenian coastal deposits of the Cilento area, Campania, which contain
two trachytic layers (CIL2, CIL1) that show the same K-alkaline affinity. Based on their chemical
compositions and radiometric ages, POP3 and POP1 are firmly correlated with the marine tephra layers
X-5 (105 2 ka) and C-22 (ca 90 ka), which, in turn, match tephras TM-25 and TM-23-11, respectively,
in the lacustrine sequence of Lago Grande di Monticchio (southern Italy). Of note, the POP1 layer also
matches the Adriatic Sea tephra PRAD 2517 that was previously correlated with the older X-5 layer. The
tephra couplet POP2a and POP2b (ca 103 and 103.5 ka, extrapolated ages) are compatible with the TM-
24b and TM-24-3 tephras in Monticchio, which match both the stratigraphic positions and the chemical
compositions. In the Cilento area, as well as the already described X-6 layer (ca 108 ka) (CIL2), we
recognise a new stratigraphic superimposed layer (CIL1) that matches the POP3/TM-25/C-27/X-5
Mediterranean marker(s). In summary, the data presented here provide new chemical and 40Ar/39Ar
chronological constraints towards a robust late MIS 5 tephrostratigraphy of the central Mediterranean,
although at the same time, they also reveal how the tephrostratigraphy itself might be flawed when
dealing with tephra markers that are not adequately constrained and characterised.Published31-451V. Storia eruttivaJCR Journa
Pescadores e botos : histĂłrias de uma conexĂŁo em rede
"Todo mundo deveria saber o que acontece aqui, sobre os botos e da pesca com eles. Saber como eles ajudam o pescador...”. Com o objetivo de contribuir para a conservação da pesca cooperativa na Barra do Rio TramandaĂ a partir de um instrumento didático, realizamos uma investigação qualitativa, que recorreu a abordagens do campo da antropologia visual (fotografia) e de relatos orais de mĂ©todos biográficos (histĂłrias de vida/depoimentos). A interação entre essas estratĂ©gias permitiu a construção de uma exposição fotográfica itinerante, construĂda com curadoria dos prĂłprios sujeitos que a significam. Enquanto a imagem parece capaz de valorizar os pescadores e sua prática cultural de forma estĂ©tica, as narrações baseadas em histĂłrias ampliam oportunidades de expressĂŁo e protagonismo destes pescadores artesanais.This study aims at contributing to the conservation of the human–dolphin cooperative fishery in the ImbĂ©/TramandaĂ estuary, south Brazil. We used an educational, sensitizing tool to carry out a qualitative survey, based on both the visual anthropology approach (photography) and oral accounts of life stories/testimonials (biographical method). The combination of these approaches lead us to produce an itinerant photography exhibition exploring human–dolphin cooperative fishery, under curatorship of fishermen themselves. While photography enhances fishermen and their cultural practice aesthetically, biographical testimonials expands their way of expressing themselves and our and our ability to help preserve human-dolphin interactions
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