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Toward an estimation of the relationship between cyclonic structures and damages at the ground in Europe
Cyclonic systems dominate European and Mediterranean meteorology throughout the year and often induce severe weather in terms of heavy and/or long-lasting precipitation with related phenomena such as strong winds and lightning. Surface cyclonic structures are often related to well defined precipitation patterns with different scales, duration and intensity. Cyclones confined in the upper troposphere, usually referred to as cut off low, may induce instability at lower levels and the development of convective precipitation.
In this work the occurrence of cyclonic events (discriminated between surface ones and cut-off lows) is analyzed and matched with an economic losses database to highlight a relation between the atmospheric structures and the impact on the social environment in terms of casualties and material damages. The study focus on the continental Europe and, based on the ERA-40 reanalysis, two databases of surface cyclones and cut-off lows have been constructed by means of automatic pattern recognition algorithms. The impact on the local communities is estimated from an insurance company record, which provides the location, date and type of the events, as well as related losses in terms of damages and casualties. Results show the relatively high impact of cyclonic structures on human life in Europe: most of the weather induced damages occur close to a cyclonic center, especially during warm months. Damages and human losses are more frequent from late summer to January, and precipitation is the most relevant meteorological damaging feature throughout the year
Ballistic accretion on a point seed
We carefully discuss the two-dimensional ballistic aggregation process. Studying the microscopic discrete process, we theoretically derive the probability density function describing the single-particle accretion. Using this function, we describe the properties of the âfanâ, obtained for ballistic aggregation on the single seed, and we predict its mean density and its opening angle. We discuss the shadowing effect on a microscopic scale, between the single particles and, on a larger scale, between grown structures, deriving the columnar microstructure direction law. Comparisons with numerical experiments are shown
Does education protect families' well-being in times of crisis? Measurement issues and empirical findings from IT-SILC data
This study analyses the relationship between education and material well-being from a longitudinal perspective using the European Survey on Income and Living Conditions (EU-SILC) data collected in Italy in four waves (2009-2012). It has two main aims: (i) to measure household material well-being on the basis of householders' responses to multiple survey items (addressed to gather information on the household availability of material resources) by advancing indexes, which can account for global and relative divergences in households' material well-being across survey waves; (ii) to assess how education and other sociodemographic characteristics affect absolute well-being and its variation (i.e. relative well-being) in the time span considered. Both aims are pursued, combining measuring and explanatory modelling approaches. That is, the use of the Multilevel Item Response Theory model allows to measure the global household material well-being and its yearly variation (i.e. relative material well-being) in the four waves. Meanwhile, the use of a multivariate (and multivariate multilevel) regression model allows to assess the effects of education and other sociodemographic characteristics on both components (absolute and relative well-being), controlling for the relevant sources of heterogeneity in the data. The value added to using the proposed methodologies with the main findings and economic implications are discussed
A Catalytic One-Pot Synthesis of Indolyl Cyclobutanones
A general strategy for the synthesis of indolyl cyclobutanones via a tandem Bronsted acid catalyzed 2-hydroxycyclobutanone activation-indole nucleophilic addition has been exploited. The procedure leads to a wide range of 2- and 3-functionalized indole derivatives in good to high yields with broad substrate scope
Asymptotically equivalent prediction in multivariate geostatistics
Cokriging is the common method of spatial interpolation (best linear unbiased prediction) in multivariate geo-statistics. While best linear prediction has been well understood in univariate spatial statistics, the literature for the multivariate case has been elusive so far. The new challenges provided by modern spatial datasets, being typ-ically multivariate, call for a deeper study of cokriging. In particular, we deal with the problem of misspecified cokriging prediction within the framework of fixed domain asymptotics. Specifically, we provide conditions for equivalence of measures associated with multivariate Gaussian random fields, with index set in a compact set of a d-dimensional Euclidean space. Such conditions have been elusive for over about 50 years of spatial statistics. We then focus on the multivariate Matern and Generalized Wendland classes of matrix valued covariance functions, that have been very popular for having parameters that are crucial to spatial interpolation, and that control the mean square differentiability of the associated Gaussian process. We provide sufficient conditions, for equivalence of Gaussian measures, relying on the covariance parameters of these two classes. This enables to identify the parameters that are crucial to asymptotically equivalent interpolation in multivariate geostatistics. Our findings are then illustrated through simulation studies
Analysis of elastic nonlinearity for impact damage detection in composite laminates
This paper concerns the experimental analysis of nonlinear response features of a
composite laminate plate for impact damage detection. The measurement procedure is based on
the Scaling Subtraction Method (SSM) and consists in exciting the damaged specimen with two
sinusoidal signals at different amplitude. The linearly rescaled response signal at low amplitude
excitation is subtracted from the response at large amplitude excitation to extract the nonlinear
signatures. The latter are analysed in the time domain to infer the presence of damage. Results
are compared with frequency domain analyses using the nonlinear vibro-acoustic modulation
technique (NWMS). Changes in amplitude and phase as well as modulation effects of the
acquired responses are also monitored. Surface-bonded, low profile piezoceramic transducers
are used for excitation and sensing. Both measurements techniques are applied to detect barely
visible impact damage in laminate composite plate. Non-destructive penetrant-enhanced X-ray
inspections are carried out to characterize the extent of internal damage. The behavior of the
nonlinear features and the sensitivity of each technique are also investigated in the paper
PM-GCD â a combined IRâMW satellite technique for frequent retrieval of heavy precipitation
Abstract. Precipitation retrievals based on measurements from microwave (MW) radiometers onboard low-Earth-orbit (LEO) satellites can reach high level of accuracy â especially regarding convective precipitation. At the present stage though, these observations cannot provide satisfactory coverage of the evolution of intense and rapid precipitating systems. As a result, the obtained precipitation retrievals are often of limited use for many important applications â especially in supporting authorities for flood alerts and weather warnings. To tackle this problem, over the past two decades several techniques have been developed combining accurate MW estimates with frequent infrared (IR) observations from geosynchronous (GEO) satellites, such as the European Meteosat Second Generation (MSG). In this framework, we have developed a new fast and simple precipitation retrieval technique which we call Passive Microwave â Global Convective Diagnostic, (PM-GCD). This method uses MW retrievals in conjunction with the Global Convective Diagnostic (GCD) technique which discriminates deep convective clouds based on the difference between the MSG water vapor (6.2 ÎŒm) and thermal-IR (10.8 ÎŒm) channels. Specifically, MSG observations and the GCD technique are used to identify deep convective areas. These areas are then calibrated using MW precipitation estimates based on observations from the Advanced Microwave Sounding Unit (AMSU) radiometers onboard operational NOAA and Eumetsat satellites, and then finally propagated in time with a simple tracking algorithm. In this paper, we describe the PM-GCD technique, analyzing its results for a case study that refers to a flood event that struck the island of Sicily in southern Italy on 1â2 October 2009
Chemical Profile and Biological Activity of Cherimoya (Annona cherimola Mill.) and Atemoya (Annona atemoya) Leaves
Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and identified 18 compounds, either flavonoids or alkaloids. Concerning biological activity, we found antioxidative properties correlated with polyphenols, and antiproliferative activity against HeLa and HepG2 cell lines correlated with alkaloids. The obtained results demonstrate the potential use of Annona cherimola leaves for the preparation of dietary supplements aimed to promote the physiological redox balance. Moreover, the varietal comparison suggests that two commercial cultivars (Campas and White) and the local Torre 1, better suit this purpose. On the other hand, among the studied cultivars, Campas and Torre 1 are also the richest in alkaloids and, in consideration of the anti-proliferative properties of their extracts, dietary supplements based on these cultivars might also have chemo-preventive effects
Study of macular and optic disk blood flow by angioâOCT in Glucoseâ6âPhosphate Dehydrogenase (G6PD) deficient men and ageârelated G6PDânormal subjects
Purpose: The reported prevalence of Glucoseâ6âPhosphate Dehydrogenase (G6PD) deficiency in Sardina, Italy, ranges from 8% to 15%. Hemizygous males have totally deficient erythrocytes. Evidence indicates that patients with G6PD deficiency are protected against ischemic heart and cerebrovascular disease, colorectal cancer, retinal vein occlusion, and nonarteritic anterior ischemic optic neuropathy. The purpose of this study was to study the macular and optic disk blood flow by angioâOCT in G6PDâdeficient men and ageârelated G6PDânormal subjects and ascertain whether, or not, there are statistically significant differences between the two groups
Methods: 22 G6PDâdeficient men and 22 perfectly ageâmatched G6PDânormal controls were examined at the Ophthalmology Unit, University of Sassari, Sassari, Italy. A complete review of the medical history and a complete ophthalmological examination, including ETDRS best corrected visual acuity, slitâlamp biomicroscopy of the anterior segment, applanation tonometry, and fundus examination, was carried out. An HD 6âmm AngioâRetina and a 4.5âmm Angio Disk (RTâVue, Optovue XRâ100 with Angio Vue, CA) examination were also performed
Results: Only 1 eye per patients was included in the analysis, for a total of 22 eyes in each group. All the exported parameters about retinal and disk flow were evaluated. No statistical differences between the two groups were found, even after controlling for the effects of age, hypertension and hypercholesterolemia (p = 0.9).
Conclusions: Results suggest that G6PDâdeficient and G6PDânormal men have similar macular and optic disk blood flow. Larger scale studies are necessary to confirm these findings
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