966 research outputs found
UWB processing applied to multifrequency radar sounders. The case of MARSIS and comparison with SHARAD
We readapt ultrawideband (UWB) processing to
enhance the range resolution of the Mars Advanced Radar for
Subsurface and Ionosphere Sounding (MARSIS) up to a factor
of 6 (25 m). The technique provides for the estimation of radar
signature over a wider spectrum via the application of wellknown super-resolution (SR) techniques to adjoining subbands.
The measured spectra are first interpolated and then extrapolated
outside the original bands. The revised algorithm includes the
estimation and removal of ionospheric effects impacting the
two signals. Because the processing requires the realignment of
the echoes at different frequencies, we derived the maximum
tolerable retracking error to obtain reliable super-resolved range
profiles. This condition is fulfilled by low-roughness areas compared to MARSIS wavelength, which proves to be suitable for the
application of our processing. Examples of super-resolved experimental products over different geological scenarios show the
detection of shallow dielectric interfaces not visible from original
MARSIS products. Our results are validated by comparison with
the Shallow Radar (SHARAD) data acquired at the crossovers,
demonstrating the potential of the method to provide enhanced
imaging capabilities
DE HEGEMONĂAS, INSTITUCIONALIDADES Y BIG DATA: OTRA PULSIĂN DESLABORALIZADORA
El presente trabajo se orienta a constituirse en un aporte preliminar para el debate en torno a las nuevas tecnologĂas y el futuro del trabajo. Particularmente, con relaciĂłn a la denominada big data. Es nuestro propĂłsito señalar aspectos de esta temĂĄtica en vista a atender nuevos escenarios y permitir esbozar estrategias tutelares hacia lo laboral que no caigan en meras generalizaciones antagĂłnicas ante el discurso neoliberal prevalente
BASEL III: Long-term impact on economic performance and fluctuations
We assess the long-term economic impact of the new regulatory standards (the Basel III reform), answering the following questions. (1) What is the impact of the reform on long-term economic performance? (2) What is the impact of the reform on economic fluctuations? (3) What is the impact of the adoption of countercyclical capital buffers on economic fluctuations? The main results are the following. (1) Each percentage point increase in the capital ratio causes a median 0.09 percent decline in the level of steady state output, relative to the baseline. The impact of the new liquidity regulation is of a similar order of magnitude, at 0.08 percent. This paper does not estimate the benefits of the new regulation in terms of reduced frequency and severity of financial crisis, analysed in Basel Committee on Banking Supervision (BCBS, 2010b). (2) The reform should dampen output volatility; the magnitude of the effect is heterogeneous across models; the median effect is modest. (3) The adoption of countercyclical capital buffers could have a more sizeable dampening effect on output volatility. These conclusions are fully consistent with those of the reports by the Long-term Economic Impact group (BCBS, 2010b) and Macro Assessment Group (MAG, 2010b).Basel III, countercyclical capital buffers, financial (in)stability, procyclicality, macroprudential policy.
Food Coloring Agents and Plant Food Supplements Derived from Vitis vinifera: A New Source of Human Exposure to Ochratoxin A
Grape pomaces are increasingly being used as starting material in the industrial production of plant food supplements (PFS), food coloring, and tartrates, but they are at risk of ochratoxin A (OTA) contamination, a mycotoxin with nephrotoxic and carcinogenic effects. We analyzed 24 commercial PFS and 13 food coloring samples derived from Vitis vinifera, mainly pomaces, using a HPLCâFLD method for OTA determination. OTA was found in 75% of PFS samples and 69% of food coloring samples at levels of <1.16â20.23 ÎŒg/kg and <1.16â32.00 ÎŒg/kg, respectively. The four commercial leavening agents containing tartrates were found to be negative for OTA. All eight samples collected in two distilleries that use grape pomaces and wine lees to produce tartrates and other byproducts contained OTA at levels of <1.16â240.93 ÎŒg/kg. The high incidence of OTA contamination in PFS and food coloring agents derived from V. vinifera suggests that maximum permitted level(s) should be established for this mycotoxin in these products
Assessment of âSugranineteenâ Table Grape Maturation Using Destructive and Auto-Fluorescence Methods
The optimal harvesting of table grapes is commonly determined based on technological and phenolic indices analyzed over the course of its maturity. The classical techniques used for these analyses are destructive, time-consuming, and work for a limited number of samples that may not represent the heterogeneity of the vineyard. This study aimed to follow the ripening season of table grapes using non-destructive tools as a rapid and accurate alternative for destructive techniques. Grape samples were collected from a Sugranineteen vineyard during the ripening season to measure the basic maturity indices via wet chemistry, and total polyphenols, anthocyanins, and flavonoids were evaluated by spectrophotometry. Fluorescent readings were collected from intact clusters with a portable optical sensor (MultiplexÂź 3, Force-A, France) that generates indices correlated to different maturity parameters. Results revealed strong relationships between the MultiplexÂź indices ANTH_RG and FERARI and the skin anthocyanin content, with R2 values equal to 0.9613 and 0.8713, respectively. The NBI_R index was also related to total anthocyanins (R2 = 0.8032), while the SFR_R index was linked to the titratable acidity (R2 = 0.6186), the sugar content (R2 = 0.7954), and to the color index of red grapes (CIRG) (R2 = 0.7835). Results demonstrated that MultiplexÂź 3 can be applied on intact clusters as an effective non-destructive tool for a rapid estimation of table grapesâ anthocyanin content
Morphometric analysis of hepatocellular nodular lesions in HCV cirrhosis
Background and aims. We generated a computerized morphometric model to evaluate and quantify the morphological features in large regenerative nodules (LRN), high-grade dysplastic nodules (HGDN) and hepatocellular carcinoma (HCC).
Methods. Sixteen LRN, 10 HGDN and 16 HCC in HCV-cirrhotic livers, were stained with H&E, smooth muscle actin, CD34, CD31 and reticulin to evaluate volume and surface fractions.
Results. On H&E stains, the features most discriminatory between LRN, HGDN and HCC were volume fraction and number of hepatocytes nuclei in unit volume, and hepatocyte nuclear/cytoplasmic ratio. On immunohistochemistry, volume fractions of capillarised sinusoids, capillary units and isolated arteries were significantly different among all groups and highest in HCC; surface fraction of reticulin was markedly decreased in HCC.
Conclusions. Our morphometric model is an objective method of quantification of the morphological changes of the nodular lesions and it could be applied in studies involving histological evaluation of the spectrum of nodular lesions arising in the cirrhotic liver
Coring the sedimentary expression of the early Toarcian Oceanic Anoxic Event: New stratigraphic records from the Tethys Ocean
The Toarcian Oceanic Anoxic Event (T-OAE) interval was cored at Colle di Sogno and Gajum in the Lombardy Basin (Southern Alps, northern Italy). The Sogno and Gajum cores recovered 26.83 and 31.18 stratigraphic metres, respectively, of pelagic sediments consisting of marly limestones, marlstone, marly claystone, and black shale. Drilling at both sites resulted in 100\u2009% recovery of unweathered material. The pelagic succession comprises a relatively expanded black shale interval of 4.98\u2009m in the Sogno core and 15.35\u2009m in the Gajum core, with lower and upper boundaries without evidence of hiatuses. The Sogno and Gajum cores can be considered reference sections for the pelagic lower Toarcian interval of the western Tethys and will provide high-resolution micropaleontological, inorganic and organic geochemical, isotopic multiproxy data. Integrated stratigraphy and cyclostratigraphy are predicted to result in estimates of durations and rates to model the ecosystem resilience to the extreme perturbations of the T-OAE and gain a better understanding of current global changes and help provide better projections of future scenarios
Smiles as Signals of Lower Status in Football Players and Fashion Models: Evidence That Smiles are Associated With Lower Dominance and Lower Prestige
Across four studies, the current paper demonstrates that smiles are associated with lower social status. Moreover, the association between smiles and lower status appears in the psychology of observers and generalizes across two forms of status: prestige and dominance. In the first study, faces of fashion models representing less prestigious apparel brands were found to be more similar to a canonical smile display than the faces of models representing more prestigious apparel brands. In a second study, after being experimentally primed with either high or low prestige fashion narratives, participants in the low prestige condition were more likely to perceive smiles in a series of photographs depicting smiling and non-smiling faces. A third study of football player photographs revealed that the faces of less dominant (smaller) football players were more similar to the canonical smile display than the faces of their physically larger counterparts. Using the same football player photographs, a fourth study found that smiling was a more reliable indicator of perceived status-relevant personality traits than perceptions of the football players\u27 physical sizes inferred from the photographs
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