Installation and data analysis of a small network of SAR corner reflectors in Fogo, Cape Verde

Since early ninety’s Synthetic Aperture Radar Interferometry (InSAR) has been exploited for geophysical applications. InSAR technique is capable to capture information on surface deformation and can be a useful tool for monitoring active seismic and volcanic areas. Despite the capability of SAR sensors to operate in all weather and day/night conditions, SAR signal is affected by different source of noise (e.g. water vapour or instrumental noise) [Hanssen, 2001]. These disturbing sources affect the accuracy of InSAR deformation map, especially for time series analysis, and the quality control of InSAR measurements, either standard differential interferometry and Persistent Scatterers Interferometry (PSI), is not an easy task. A fruitful solution is represented by the adoption of passive Corner Reflectors (CRs). CRs can provide point measurements with high level of confidence with sub-centimeter accuracy [Marinkovic et al, 2007], thanks to their high backscattered signal value, and representing strong persistent scatterers to be used for calibrating and validating SAR (from InSAR and PSI technique) deformation map. Indeed, CRs can maintain their interferometric phase stable during time. Additionally, CRs can also be exploited to calibrate the amplitude SAR signal, and to provide reference points for geocoding purposes. Here we present the design, realization and installation of a small CRs network on the Fogo Volcano island, Cape Verde. This activity has been done in the framework of the European project MIAVITA, MItigate and Assess risk from Volcanic Impact on Terrain and human Activities

Formal Versus Functional Method in Comparative Constitutional Law

In the field of comparative constitutional law, the dominant approach to concept formation and research design is formal. That is, comparative projects generally identify what counts as the supreme law that can be enforced against all other sources of law based on the “constitutional” label of the positive law (written constitutions and the jurisprudence of constitutional courts) and the law books. This formal method, however, has significant limitations when compared with the functional method used in the field of comparative law more generally speaking. After a brief exposition of the functional method, this article explores the advantages of the functional method as applied to comparative constitutional law with the problem of judicial review (based on the supreme law) of social and economic policy-making in France, the United States, and Germany. Only in Germany is this law contained in constitutional law. In France, the supreme law is to be found largely in administrative law, because the constitutional court faces an institutional competitor, some would say superior, in the highest administrative court (Conseil d’État). In the United States, the supreme law is to be found in administrative law because economic and social rights—the rights that most directly affect this area of state activity—have largely been read out of constitutional law. Based on the functional method, the article proceeds to identify the similarities that unite the law of France and Germany and that set it apart from the law of the United States. It also outlines the important avenues of theoretical inquiry triggered by these similarities and differences in judicial review. The article concludes by sketching a functional agenda for empirical research in comparative constitutional law

INDAGINE SULLA PRESENZA DI PATOGENI ZOONOSICI IN ALLEVAMENTI DI BOVINE DA LATTE DEL COMPENSORIO LOMBARDO

Milk bacterial quality at farm gate has gradually improved in the last decades in Italy, and in Lombardia. Further more raw milk consumption is raising public concern about the risk of foodborne disease by emerging pathogens. The aim of the present study is to evaluate the real presence of such bacteria in different dairy herds. Two groups of dairy were analized: 22 were located in Milano-Lodi area, and chosen based on bulk milk total bacterial count registred during the last 3 years; they were visited 3 times in different seasons. The second group were 42 dairy located in Como-Lecco area. In all of these herd cows are housed in cubicles and milked in herringbone parlours. The following samples were taken: bulk milk, milk machine filters and 3 environmental samples. Each samples was microbiologically tested for the presence of S.aureus, Salmonella spp., L.monocitogenes, Campyloacter spp.,EHEC,Yersinia enterocolitica and MAP. The presumptive isolation was confirmed by PCR.The presence of MAP was investigaqted by Real-Time PCR. Only S.aureus positive milk samples was higher in the herds. MAP showed similar frequency, but a random distribution. With the exeption of Y.entercolitica, that was isolated in 1 herd, all the other pathogens were never detected in the milk or in the filter. Frequentely we isolated EHEC and MAP in environmental samples, while neither Salmonella spp. Nor Campylobacter spp.. were demonstrated. When proper hygienic procedures during milking are applied, the risk of milk contamination by foodborne pathogens in very low

Search for periodicities near 59 s in the COS-B gamma-ray data of 2CG195+04 (Geminga)

The COS-B data relating to five observations in the general direction of Geminga, spanning 6.7 years, were searched for pulsation near 59 s. The SAS-2 indication is not confirmed. An indication of a 59 s pulsation in the gamma ray emission from 2CG195+04 (Geminga) was reported. Early analysis of COS-B data supported the result while later improved statistics did not confirm it. Subsequently, detection of a 59 s pulsation in the emission from the direction of Geminga at ultra high gamma and X-rays was reported. Geminga was identified with the X-ray source 1E0630+128. The final COS-B data on Geminga which was observed five times for a total of 214 days are reported

The Milagro anticenter hot spots: cosmic rays from the Geminga supernova ?

The Milagro experiment has announced the discovery of an excess flux of TeV cosmic rays from the general direction of the heliotail, also close to the Galactic anticenter. We investigate the hypothesis that the excess cosmic rays were produced in the SN explosion that gave birth to the Geminga pulsar. The assumptions underlying our proposed scenario are that the Geminga supernova occurred about 3.4 10^5 years ago (as indicated by the spin down timescale), that a burst of cosmic rays was injected with total energy 10^49 erg (i.e., about 1% of a typical SN output), and that the Geminga pulsar was born with a positive radial velocity of 100--200 km s^-1. We find that our hypothesis is consistent with the available information. In a first variant (likely oversimplified), the cosmic rays have diffused according to the Bohm prescription (i.e., with a diffusion coefficient on the order of c times r_L, with c the speed of light and r_L the Larmor radius). An alternative scheme assumes that diffusion only occurred initially, and the final propagation to the Sun was a free streaming in a diverging magnetic field. If the observed cosmic ray excess does indeed arise from the Geminga SN explosion, the long--sought "smoking gun" connecting cosmic rays with supernovae would finally be at hand. It could be said that, while looking for the "smoking gun", we were hit by the bullets themselves.Comment: Astronomy and Astrophysics, accepted; includes modifications suggested by the referee; 4 pages and 1 figur

The final COS-B database now publicly available

The data obtained by the gamma ray satellite COS-B was processed, condensed and integrated together with the relevant mission and experiment parameters into the Final COS-B Database. The database contents and the access programs available with the database are outlined. The final sky coverage and a presentation of the large scale distribution of the observed Milky Way emission are given. The database is announced to be available through the European Space Agency

Cyg X-3: Not seen in high-energy gamma rays by COS-B

COS-B had Cyg X-3 within its field of view during 7 observation periods between 1975 and 1982 for in total approximately 300 days. In the skymaps (70 meV E 5000 meV) of the Cyg-X region produced for each of these observations and in the summed map, a broad complex structure is visible in the region 72 deg approximately less than 1 approximately less than 85 deg, approximately less than 5 deg. No resolved source structure is visible at the position of Cyg X-3, but a weak signal from Cyg X-3 could be hidden in the structured gamma-ray background. Therefore, the data has been searched for a 4.8 h timing signature, as well as for a source signal in the sky map in addition to the diffuse background structure as estimated from tracers of atomic and molecular gas

Diffractive Interaction and Scaling Violation in pp->pi^0 Interaction and GeV Excess in Galactic Diffuse Gamma-Ray Spectrum of EGRET

We present here a new calculation of the gamma-ray spectrum from pp->pi^0 in the Galactic ridge environment. The calculation includes the diffractive pp interaction and incorporates the Feynman scaling violation for the first time. Galactic diffuse gamma-rays come, predominantly, from pi^0->gamma gamma in the sub-GeV to multi-GeV range. Hunter et al. found, however, an excess in the GeV range ("GeV Excess") in the EGRET Galactic diffuse spectrum above the prediction based on experimental pp->pi^0 cross-sections and the Feynman scaling hypothesis. We show, in this work, that the diffractive process makes the gamma-ray spectrum harder than the incident proton spectrum by ~0.05 in power-law index, and, that the scaling violation produces 30-80% more pi^0 than the scaling model for incident proton energies above 100GeV. Combination of the two can explain about a half of the "GeV Excess" with the local cosmic proton (power-law index ~2.7). The excess can be fully explained if the proton spectral index in the Galactic ridge is a little harder (~0.2 in power-law index) than the local spectrum. Given also in the paper is that the diffractive process enhances e^+ over e^- and the scaling violation gives 50-100% higher p-bar yield than without the violation, both in the multi-GeV range.Comment: 35 pages, 11 figures, to appear in Astrophysical Journa

Simultaneous X-ray and Radio Monitoring of the Unusual Binary LSI+61 303: Measurements of the Lightcurve and High-Energy Spectrum

The binary system, LSI+61 303, is unusual both because of the dramatic, periodic, radio outbursts, and because of its possible association with the 100 MeV gamma-ray source, 2CG135+01. We have performed simultaneous radio and Rossi X-ray Timing Explorer X-ray observations at eleven intervals over the 26.5 day orbit, and in addition searched for variability on timescales ranging from milliseconds to hours. We confirm the modulation of the X-ray emission on orbital timescales originally reported by Taylor et al. (1996), and in addition we find a significant offset between the peak of the X-ray and radio flux. We argue that based on these results, the most likely X-ray emission mechanism is inverse Compton scattering of stellar photons off of electrons accelerated at the shock boundary between the relativistic wind of a young pulsar and the Be star wind. In these observations we also detected 2 -- 150 keV flux from the nearby low-redshift quasar QSO~0241+622. Comparing these measurements to previous hard X-ray and gamma-ray observations of the region containing both LSI+61 303 and QSO~0241+622, it is clear that emission from the QSO dominates.Comment: 23 pages, 6 figures, Accepted for publication in the Astrophysical Journa