Ion produced cometary organic crust

For several years many experimental results have been obtained on the chemical and physical changes induced by ion and electron irradiation of materials with a view to their Astrophysical relevance. Among the studied effects, one of particular interest is the formation of an organic refractory residue left over after ion irradiation and warming-up at room temperature. We call this residue IPHAC (ion produced hydrogenated amorphous carbon). Although 'in situ' infrared spectroscopy points out the formation of new molecular species during bombardment at low temperature, it is not clear if IPHAC is already formed or if its formation is triggered by temperature increase during warming-up of the irradiated target. Since Raman Spectroscopy is a technique particularly suitable for the analysis of carbonaceous materials, we have thought and build-up an experimental apparatus to obtain Raman Spectra of frozen hydrocarbons during ion irradiation. The present experimental results point out clearly to the formation of IPHAC already at low T and low energy deposition (approximately equal to a few eV/C-atom)

Forme di devozione nei luoghi di culto dell’Abruzzo antico

The paper is dealing with the forms of votive religion in a region of Italy, corresponding to the modern Abruzzo, which during ancient times had been inhabited by Italic people, such as Pretuzi, Vestini, Equi, Marsi, Peligni and Marrucini. It addresses chronological issues, (i.e., the onset of votive offerings, their relationship with cult places and sacred buildings, and the moment on their disappearence), problems related to the meaning to be attributed to the different types of supply (bronze, terracotta, pottery) and historicalideological issues, particularly with regard to theme of the Romanization of the territory and of the adhesion of different social classes to a model of religious import. Finally, some examples illustrate the problem of the relationship between a votive offering and the worship of a particular deity

HUMAN CAPITAL AND FAMILY FARM IN THE OLIVE GROWING SYSTEM OF THE CALABRIA REGION

This research aims at pointing out those constrains and incentives conditioning family farm choices about investments, technical and managerial knowledge and expertness. The planned target has to be achieved through the attainment of three stages. Family farm involves a lot of people by different kind of employee relations, based mostly on a temporary work, that are often within the limits of the work rules. The organization solutions adopted by family farm produce several effects: among which investments and human capital allotment stand out. This research analyses family farm characteristics in a local rural system of the Calabria Region, as the result of the various European Community and domestic interventions and the specific physical, social and economic features in the considered territory; the attention is focused on the olive growing family farm. The survey is made through interviews carried out by qualified operators using questionnaires organized on different modules.Human capital, Family farm, Agricultural labour, Agribusiness, Labor and Human Capital,

Set-based Simulation for Design and Verification of Simulink Models

International audienceModel-based design is a widely used methodology for the development of embedded critical software, such as a discrete controller for a continuous plant. In this setting, numerical simulation of both the plant and the controller plays a crucial role, since it is used to validate the design choices in the early stages of development. However, classical numerical simulation has inherent limitations: it is of limited precision and cannot deal with the intrinsic non-determinism present in complex systems. In this article, we present a tool named HySon that overcomes these drawbacks. It takes as input a Simulink model of a control-command system with non-deterministic uncertainties and automatically computes flow-pipes that contain all possible trajectories of the system. We show on some examples how HySon can be used to improve the quality of model-based design

Isolated laryngeal leishmaniasis in immunocompetent patients: an underdiagnosed disease.

We describe a case of isolated primary laryngeal leishmaniasis in an immunocompetent Italian patient with a previous medical history negative for visceral or cutaneous leishmaniasis, presenting with hoarseness. We also summarize the epidemiological, clinical, and diagnostic features and the therapeutic management of other cases of laryngeal leishmaniasis in immunocompetent subjects, described in the literature. Considering the insidious and nonspecific clinical presentation, the increasing number of different forms of mild or underestimated immunosuppressive conditions, and the number of people travelling in endemic zones, along with the ability of Leishmania amastigotes to survive for a long period in the body, we believe it is important for pathologists and clinicians to be aware of this unusual form of leishmaniasis in order to avoid delayed recognition and treatment. The rarity of the presentation and the lack of guidelines on mucosal leishmaniasis may contribute to the potential undiagnosed cases or delayed diagnosis, the possible relapses, as well as the correct pharmacological and/or surgical therapeutic approach

A Peculiar Family of Jupiter Trojans: the Eurybates

The Eurybates family is a compact core inside the Menelaus clan, located in the L4 swarm of Jupiter Trojans. Fornasier et al. (2007) found that this family exhibits a peculiar abundance of spectrally flat objects, similar to Chiron-like Centaurs and C-type main belt asteroids. On the basis of the visible spectra available in literature, Eurybates family's members seemed to be good candidates for having on their surfaces water/water ice or aqueous altered materials. To improve our knowledge of the surface composition of this peculiar family, we carried out an observational campaign at the Telescopio Nazionale Galileo (TNG), obtaining near-infrared spectra of 7 members. Our data show a surprisingly absence of any spectral feature referable to the presence of water, ices or aqueous altered materials on the surface of the observed objects. Models of the surface composition are attempted, evidencing that amorphous carbon seems to dominate the surface composition of the observed bodies and some amount of silicates (olivine) could be present.Comment: 23 pages, 2 figures, paper accepted for publication in Icaru

Collisions, Cosmic Radiation and the Colors of the Trojan Asteroids

The Trojan asteroids orbit about the Lagrangian points of Jupiter and the residence times about their present location are very long for most of them. If these bodies originated in the outer Solar System, they should be mainly composed of water ice, but, in contrast with comets, all the volatiles close to the surface would have been lost long ago. Irrespective of the rotation period, and hence the surface temperature and ice sublimation rate, a dust layer exists always on the surface. We show that the timescale for resurfacing the entire surface of the Trojan asteroids is similar to that of the flattening of the red spectrum of the new dust by solar-proton irradiation. This, if the cut-off radius of the size distribution of the impacting objects is between 1mm and 1m and its slope is -3, for the entire size-range. Therefore, the surfaces of most Trojan asteroids should be composed mainly of unirradiated dust.Comment: In press in Icaru

Methane, ammonia, and their irradiation products at the surface of an intermediate-size KBO? A portrait of Plutino (90482) Orcus

Orcus is an intermediate-size 1000km-scale Kuiper Belt Object in 3:2 mean-motion resonance with Neptune, in an orbit very similar to that of Pluto. We present visible and near-infrared photometry and spectroscopy obtained with the Keck 10m-telescope and the Gemini 8m-telescope . We confirm the unambiguous detection of crystalline water ice as well as absorption in the 2.2\mu m region. Both in the visible and near-infrared Orcus' spectral properties appear to be homogeneous over time (and probably rotation) at the resolution available. From Hapke radiative transfer models involving intimate mixtures of various ices we find for the first time that ammonium (NH+4) and traces of ethane (C2 H6), which are most probably solar irradiation products of ammonia and methane, and a mixture of methane and ammonia (diluted or not) are the best candidates to improve the description of the data with respect to a simple water ice mixture (Haumea type surface). The possible more subtle structure of the 2.2\mu m band(s) should be investigated thoroughly in the future for Orcus and other intermediate size Plutinos to better understand the methane and ammonia chemistry at work, if any. We investigated the thermal history of Orcus with a new 3D thermal evolution model. Simulations over 4.5 x109 yrs with an input 10% porosity, bulk composition of 23% amorphous water ice and 77% dust, and cold accretion show that even with the action of long-lived radiogenic elements only, Orcus should have a melted core and most probably suffered a cryovolcanic event in its history which brought large amounts of crystalline ice to the surface. The presence of ammonia in the interior would strengthen the melting process. The crystalline water ice possibly brought to the surface by a past cryovolcanic event sbe detectable after several billion years despite the irradiation eects, as demonstrated by recent laboratory experiments.Comment: 15 pages, 9 figure

Space Weathering on Near-Earth Objects investigated by neutral-particle detection

The ion-sputtering (IS) process is active in many planetary environments in the Solar System where plasma precipitates directly on the surface (for instance, Mercury, Moon, Europa). In particular, solar-wind sputtering is one of the most important agents for the surface erosion of a Near-Earth Object (NEO), acting together with other surface release processes, such as Photon Stimulated Desorption (PSD), Thermal Desorption (TD) and Micrometeoroid Impact Vaporization (MIV). The energy distribution of the IS-released neutrals peaks at a few eVs and extends up to hundreds of eVs. Since all other release processes produce particles of lower energies, the presence of neutral atoms in the energy range above 10 eV and below a few keVs (Sputtered High-Energy Atoms - SHEA) identifies the IS process. SHEA easily escape from the NEO, due to NEO's extremely weak gravity. Detection and analysis of SHEA will give important information on surface-loss processes as well as on surface elemental composition. The investigation of the active release processes, as a function of the external conditions and the NEO surface properties, is crucial for obtaining a clear view of the body's present loss rate as well as for getting clues on its evolution, which depends significantly on space weather. In this work, an attempt to analyze the processes that take place on the surface of these small airless bodies, as a result of their exposure to the space environment, has been realized. For this reason a new space weathering model (Space Weathering on NEO - SPAWN), is presented. Moreover, an instrument concept of a neutral-particle analyzer specifically designed for the measurement of neutral density and the detection of SHEA from a NEO is proposedComment: 36 page