New radio halos and relics in clusters of galaxies

We present here new images of relics and halo sources in rich cluster of galaxies and the correlation between the halo radio surface brightness versus the cluster bolometric X-ray luminosity.Comment: 2 pages, 4 figures. To appear in the Proceedings of the International Conference: "The Origin and Evolution of Cosmic Magnetism"; Bologna 29 August - 2 September 2005; eds R. Beck, G. Brunetti, L. Feretti, and B. Gaensler (Astronomische Nachrichten, 2006

Stress-corrosion behavior of aluminum-lithium alloys in aqueous environments

The stress corrosion susceptibility of two powder metallurgy (P/M) alloys, Al-Li-Cu and Al-Li-Cu-Mg two mechanically attrited (M/A) alloys, Al-Li-Cu and Al-Li-Mg; and two wrought, ingot alloys, X-2020 and AA7475, are compared. Time-dependent fracture in an aqueous sodium chloride environment under alternate immersion condition was found to vary significantly between alloys. The stress corrosion behavior of the two powder metallurgy processed alloys was studied in detail under conditions of crack initiation, static crack growth, and fatigue crack growth. A variety of stress corrosion tests were performed including smooth surface, time-to-failure tests; potentiostatic tests on smooth surfaces exposed to constant applied strain rates; and fracture mechanics-type tests under static and cyclic loads. Both alloys show surface pitting and subsequent intergranular corrosion. Pitting is more severe in the magnesium-bearing alloy and is associated with stringer particles strung along the extrusion direction as a result of P/M processing

Diffuse radio emission in the complex merging galaxy cluster Abell 2069

Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms of the particle acceleration and the properties of the magnetic field are still poorly understood. We search for diffuse radio emission in galaxy clusters. Here, we study the complex galaxy cluster Abell 2069, for which X-ray observations indicate a recent merger. We investigate the cluster's radio continuum emission by deep Westerbork Synthesis Radio Telescope (WSRT) observations at 346 MHz and a Giant Metrewave Radio Telescope (GMRT) observation at 322 MHz. We find an extended diffuse radio feature roughly coinciding with the main component of the cluster. We classify this emission as a radio halo and estimate its lower limit flux density to 25 +/- 9 mJy. Moreover, we find a second extended diffuse source located at the cluster's companion and estimate its flux density to 15 +/- 2 mJy. We speculate that this is a small halo or a mini-halo. If true, this cluster is the first example of a double-halo in a single galaxy cluster.Comment: 6 pages, 3 figures, accepted for publication in A&

Laterolateral teleradiography of the skull as a screening method for OSA/OSAS, in patients in orthodontic treatment

Aim: Obstructive sleep apnea syndrome (OSAS) is the most common type of sleep apnea and it is caused by complete or partial obstruction of the upper airway. Adenotonsillar hypertrophy, obesity, cranio-facial anomalies and neuromuscular diseases are the main risk factors for the development of OSAS in the pediatric age. Specially several studies identify the relationship between respiratory disorders in sleep and obesity, and, in particular, between OSAS and obesity, designing a prevalence of OSAS among obese subjects between 14 and 78%. The diagnosis of OSAS in the child is of great importance as it can lead to neurocognitive and behavioral complications, growth retardation, systemic arterial hypertension, pulmonary hypertension, cardiovascular disease and metabolism. The WHO (World Health Organization) has established the new criteria for the classification of Obesity on the basis of BMI and the risk of comorbidities, identifying a moderate risk for underweight subjects, a very low risk for normal weights and an increased risk from severe to severe for overweight and obese individuals respectively. According to that the aim of this study is to evaluate the correlation between obstructive sleep apnea syndrome and cephalometric variables in children considering age and BMI. Materials and methods: Children aged 7–10 years and 11-14 years with no genetic syndrome, previous otorhinolaryngologic or orthodontic therapy treatments are being selected from our Departments of Paediatric Dentistry, University of Palermo, and from the Department of Orthodontics, University of Messina (Italy). All patients so far recruited and visited for orthodontic problems were in mixed or early permanent dentition phase, with the first upper molars fully erupted and presented to the history of several symptoms of Osas, such as recurring episodes of shallow or paused breathing during sleep, waking up frequently to urinate, morning headaches, memory or learning problems and not be able to concentrate or feeling irritable. Dental records and lateral cephalometric radiographs were obtained for all of the patients and than they have been subjected to paediatric, otolaryngology and polysomnography visits. Subject with a positive diagnosis of Osas were studied and they were divided in group based on their BMI. In all groups the inter-molar distance in dental records was measured, and the cephalometric traces have been calculated. As reported by the study by Galeotti et al. the cephalometric measurements analysed are S-PNS, ad1-PNS, and ad2-PNS for the nasopharynx; p-pp and pa for oropharynx; H-H’ for the Hyoid bone; SNA for the maxilla; SNB;ANB and Go-Me for the mandible; S-Go, N-Me and P-A for facial Height; SN for cranial base; SN-MP and PP-MP for the typology, and angle ArGoMe for Growth prevision. At the time that children are still in the way of recruitment the results may not yet be defined; however it is necessary to emphasize the importance of the study, because in the child respiratory disturbances in the sleep, and in particular the OSAS, are often underestimated, despite representing the third place between the threats of health after the smoke and the excess of weight

Stream dynamics between 1 AU and 2 AU: A detailed comparison of observations and theory

A radial alignment of three solar wind stream structures observed by IMP-7 and -8 (at 1.0 AU) and Voyager 1 and 2 (in the range 1.4 to 1.8 AU) in late 1977 is presented. It is demonstrated that several important aspects of the observed dynamical evolution can be both qualitatively and quantitatively described with a single-fluid 2-D MHD numerical model of quasi-steady corotating flow, including accurate prediction of: (1) the formation of a corotating shock pair at 1.75 AU in the case of a simple, quasi-steady stream; (2) the coalescence of the thermodynamic and magnetic structures associated with the compression regions of two neighboring, interacting, corotating streams; and (3) the dynamical destruction of a small (i.e., low velocity-amplitude, short spatial-scale) stream by its overtaking of a slower moving, high-density region associated with a preceding transient flow. The evolution of these flow systems is discussed in terms of the concepts of filtering and entrainment

Evaluation of milk production and some blood parameters in lactating autochthonous goat extensively reared in Molise region

The trial, lasted 7 months and was performed on 60 lactating autochthonous goat populations (Montefalcone and Valfortorina) extensively reared in Molise Region. Goat milk yield and composition, and pasture chemical and floristic composition were recorded monthly. At the beginning (30d), at half (105d) and at the end (210d) of trial body weight and body condition score (BCS) were recorded; besides jugular blood samples were taken at 30, 105 e 210 d to determined the following parameters: glucose, total protein, albumin, urea, triglycerides, total and HDL cholesterol, NEFA, calcium, magnesium, sodium and potassium. The two populations showed a milk yield of 275 kg e 258 kg (Montefalcone e Valfortorina goat, respectively) throughout 180 days of lactation, which was similar or higher than mean milk yield of other goat breeds (Sarda, Ionica, Argentata dell'Etna). BCS increased significantly (P<0.01) during lactation in both populations. Blood parameters displayed significant changes (P<0.01) during the trial in Montefalcone goat for glucose, albumin, urea, triglycerides, total and HDL cholesterol, NEFA, sodium and potassium instead Valfortorina goat showed significant differences in total protein, urea, total and HDL cholesterol, NEFA, magnesium, sodium (P<0.01) and albumin and potassium (P<0.05). In both population, milk yield and quality showed promising results for autochthonous goats preservation

The Sunyaev-Zeldovich Effect at 1 and 2 mm towards ROSAT Clusters

An observing campaign was devoted to the search for the Sunyaev-Zeldovich (S-Z) effect towards X-ray ROSAT Clusters in the millimetric spectral domain. A double channel (1.2 and 2 {\it mm}) photometer was installed at the focus of the 15m Swedish ESO Submillimeter Telescope (SEST) in Chile in september 1994 and 1995 and observations of the targets S1077, A2744, S295 and RXJ0658-5557 were gathered. Detections were found for A2744 at 1 {\it mm} and in both channels (at 1.2 and 2 {\it mm}) towards RXJ0658-5557. For the first time there is evidence for the S-Z enhancement and both the latter and the decrement were detected on the same source. We discuss astrophysical and systematic effects which could give origin to these signals.Comment: 6 pg Latex file (style file included) including 1 ps figure, XVIth Moriond Astrophysics Meeting "The Anisotropies of the Cosmic Microwave Background", Les Arcs, Savoie-France, March 16-23 199

Contributions to the Fourth Solar Wind Conference

Recent results in interplanetary physics are examined. These include observations of shock waves and post-shock magnetic fields made by Voyager 1, 2; observations of the electron temperature as a function of distance between 1.36 AU and 2.25 AU; and observations of the structure of sector boundaries observed by Helios 1. A theory of electron energy transport in the collisionless solar wind is presented, and compared with observations. Alfven waves and Alvenic fluctuations in the solar wind are also discussed