Extended radio emission in BL Lac objects - I: the images

We have observed 28 sources selected from the 1Jy sample of BL Lac objects (Stickel et al. 1991) with the Very Large Array (VLA) in A, B and D configurations at 1.36, 1.66 and 4.85 GHz, and/or with the Westerbork Synthesis Radio Telescope (WSRT) at 1.40 GHz. In this paper we present high sensitivity images at arcsecond resolution of the 18 objects showing extended structure in our images, and of another source from the FIRST (Faint Images of the Radio Sky at Twenty-cm) survey (Becker et al. 1995). In general our high sensitivity images reveal an amount of extended emission larger than previously reported. In some objects the luminosity of the extended structure is comparable with that of FR~II radio sources. A future paper will be devoted to the interpretation of these results.Comment: 12 pages, 35 figures, to appear on A&A Supp. Ser., postscript file with figures included available at http://www.ira.noto.cnr.it/staff/carlo/ds1030.ps.g

Bendings of radio jets in BL Lacertae objects I: EVN and MERLIN observations

Several blazars, and BL Lac objects in particular, show a misalignment between the jet orientation on parsec and kiloparsec scales. Some authors (i.e. Conway & Murphy, 1993) have attempted to explain this behaviour invoking helical jets for misalignment angles around 90\degr, showing how in this case there are interesting implications for the understanding of the medium into which the jet is expanding. By comparing sensitive VLA observations (Cassaro et al., 1999) with images available in the literature for the BL Lac objects from the 1-Jy Sample (Stickel et al., 1991), it is clear that there is a wide range of misalignments between the initial jet direction and the kpc-scale jet, when detected. We have carried out VLBI observations of these BL Lac objects, in order to investigate the spatial evolution of the radio jets from few tens to hundreds of mas, and to search for helical jets in this class of sources. We present here the first dataset obtained from EVN+MERLIN observations at 5 GHz for seven objects. From these observations we never have a clear detection of helical jets, we only have a possible signature of their presence in 2 objects. In only one of the sources with a misalignment angle around 90\degr the presence of helical jets can be ruled out. This implies that it is not possible to invoke helical jets to explain the morphology of all the sources showing a misalignment of about 90\degr between the parsec and the kiloparsec scale jets.Comment: 12 pages, 9 figures, latex, accepted by Astronomy & Astrophysic

Discrepancies in Obesity Levels by Three Separate Criteria (Waist Girth, BMI, and Body Fat Percentage)

Please refer to the pdf version of the abstract located adjacent to the title

Extended emission around GPS radio sources

Extended radio emission detected around a sample of GHz Peaked Spectrum (GPS) radio sources is discussed. Evidence for extended emission which is related to the GPS source is found in 6 objects out of 33. Three objects are associated with quasars with core-jet pc-scale morphology, and three are identified with galaxies with symmetric (CSO) radio morphology. We conclude that the core-jet GPS quasars are likely to be beamed objects with a continuous supply of energy from the core to the kpc scale. It is also possible that low surface brightness extended radio emission is present in other GPS quasars but the emission is below our detection limit due to the high redshifts of the objects. On the other hand, the CSO/galaxies with extended large scale emission may be rejuvenated sources where the extended emission is the relic of previous activity. In general, the presence of large scale emission associated with GPS galaxies is uncommon, suggesting that in the context of the recurrent activity model, the time scale between subsequent bursts is in general longer than the radiative lifetime of the radio emission from the earlier activity.Comment: 18 paged, 18 figures, accepted for publication on A&

Modeling and validation of aircraft mathematical models for the development of an innovative Flight Management System

This paper reports the experience of the MAS_Lab (Multipurpose Aircraft Simulation Laboratory) project, developed at the Politecnico di Torino within the Clean Sky ITD Systems for Green Operations. The complete project environment is briefly described and the MAS_Lab tasks are discussed. Modeling design choices are investigated, highlighting those concerning simulator structure and automatic flight control laws; the validation process is described, focusing on the techniques used to assess model accuracy. Examples of results obtained during the validation campaign are presented, with the intention of showing how model validation and autopilot performance are considered satisfactory

The effect of immersion disinfection procedures on dimensional stability of two elastomeric impression materials

The aim of this study was to determine the effect of immersion disinfection procedures on the dimensional stability of two elastomeric impression materials. Impressions of a stainless steel die were made with polyether (PE) and with additionpolymerized silicone rubber (PVS). The test specimens underwent disinfection treatment by immersion in two commercially available solutions containing quaternary ammonium compounds (Sterigum Powder, SP) and glutaraldehyde plus an amino derivative (MD520, MD), respectively. The impressions were measured at 4 different time points: before any disinfection treatment (T0); after the first disinfection (T1); 6 hours after the first disinfection (T2); after the second disinfection, carried out 6 hours after the first one (T3). Impressions which were not disinfected served as controls. When both impression materials were disinfected with SP, significant differences were detected among all measurements (P < 0.0001), with the exception of T2 vs T3 (P > 0.05). On the other hand, when MD was used, significant differences were found when T0 measurement was compared to T1, T2 and T3 measurements (P = 0.0043 for PE, and P = 0.0014 for PVS). The dimensional change of all material/disinfectant combinations was always ≤0.5%. Therefore, the effects of immersion disinfection on the dimension of elastomers in SP or MD are not clinically relevan

Alteração da fertilidade do solo cultivado com cafeeiro conilon submetido a três níveis de fertilização com NPK.

Os solos do Estado de Rondônia, na extensão Noroeste do território brasileiro, apresentam grande variabilidade física e química. Na região norte do estado, onde se localiza o Munícipio de Porto Velho, os solos são, em sua maioria, ácidos, com porcentagem de saturação por alumínio acima de 50%, de baixa fertilidade química apresentando valores baixos para soma de bases, capacidade de troca de cátions e saturação por bases. O objetivo neste estudo foi avaliar as alterações na fertilidade do solo cultivado com cafeeiro ?Conilon? submetido à fertilização química com NPK. Os tratamentos estudados foram três níveis de fertilização com N, P e K (N1: 90-50-150; N2: 150-90-270 e N3: 210-130-390 kg ha-1) combinados com três camadas de avaliação 0-10; 10-20 e 20-40 cm de profundidade. O experimento foi conduzido em esquema de parcelas subdivididas 3x3 com três repetições no delineamento de blocos casualizados. Avaliou-se os atributos químicos do solo pH e os teores de P, K, Ca Mg, Al+H, Al, MO e V (%). Os atributos químicos dos solos não foram influenciados pelos três níveis de fertilizantes (NPK) empregados aos 14 meses após a implantação. Os atributos químicos do solo apresentaram condições mais favoráveis na camada superficial (0-10 e 10-20 cm), em relação à camada de 20-40 cm

An Oxalate-Bridged Copper(II) Complex Combining Monodentate Benzoate, 2,2'-bipyridine and Aqua Ligands:Synthesis, Crystal Structure and Investigation of Magnetic Properties

A dinuclear copper(II) complex of formula [{Cu(bipy)(bzt)(OH2)}2(μ-ox)] (1) (where bipy = 2,2'-bipyridine, bzt = benzoate and ox = oxalate) was synthesised and characterised by diffractometric (powder and single-crystal XRD) and thermogravimetric (TG/DTG) analyses, spectroscopic techniques (IR, Raman, electron paramagnetic resonance spectroscopy (EPR) and electronic spectroscopy), magnetic measurements and density functional theory (DFT) calculations. The analysis of the crystal structure revealed that the oxalate ligand is in bis(bidentate) coordination mode between two copper(II) centres. The other four positions of the coordination environment of the copper(II) ion are occupied by one water molecule, a bidentate bipy and a monodentate bzt ligand. An inversion centre located on the ox ligand generates the other half of the dinuclear complex. Intermolecular hydrogen bonds and π-π interactions are responsible for the organisation of the molecules in the solid state. Molar magnetic susceptibility and field dependence magnetisation studies evidenced a weak intramolecular-ferromagnetic interaction (J = +2.9 cm-1) between the metal ions. The sign and magnitude of the calculated J value by density functional theory (DFT) are in agreement with the experimental data

Coleção ativa de germoplasmas de Coffea arabica L.: situação atual, caracterização e perspectivas para Rondônia.

Em Rondônia, cultivares da espécie arábica (Coffea arabica L.; Rubiaceae) são plantadas em apenas 5 % da área total (160 mil hectares) do parque cafeeiro estadual, dentre outros motivos, por causa da C. arabica apresentar restrita variabilidade genética para os caracteres de importância adaptativa, econômica e de defensividade nas condições ambientais da Amazônia Ocidental. As principais cultivares comerciais brasileiras de C. arabica são muito aparentadas entre si por serem exclusivamente descendentes das populações-base Bourbon e Typica. De 1978 a 2000, foram introduzidos e avaliados, aproximadamente, 120 acessos de C. arabica provenientes de várias instituições brasileiras de pesquisa agropecuária. O objetivo deste trabalho foi realizar a caracterização preliminar dos acessos de cafeeiros arábica, mantidos na Coleção Ativa de Germoplasma da Embrapa Rondônia em Ouro Preto d’Oeste, RO. Utilizaram-se 26 acessos (cultivares e linhagens irmãs) de C. arabica, provenientes dos principais programas de melhoramento genético do cafeeiro arábica do Brasil. Foram avaliadas 28 características por meio de descritores (morfológicos e agronômicos) mínimos diferenciadores, atualmente usados para registro ou proteção de cultivares comercial de café. A utilização conjunta da maioria dos descritores usados neste trabalho possibilitou, com relativa facilidade, discriminar fenotipicamente as cultivares cafeeiras entre si. A coloração das folhas jovens e dos frutos maduros são os descritores genéticos qualitativos mais facilmente identificáveis e que mais contribuíram na distinção eficiente dos germoplasma cafeeiros caracterizados. O uso das variáveis descritoras qualitativas (coloração dos brotos, cor dos frutos maduros, porte da planta e ciclo de maturação) foram eficientes na caracterização dos acessos estudados. De modo geral, estes resultados são concordantes com outros trabalhos similares realizados com a maioria das cultivares e,ou linhagens caracterizadas.bitstream/item/45456/1/bpd67-cafe.pd