86 GHz Very Long Baseline Polarimetry of 3C273 and 3C279 with the Coordinated Millimeter VLBI Array

86 GHz Very Long Baseline Polarimetry probes magnetic field structures within the cores of Active Galactic Nuclei at higher angular resolutions and a spectral octave higher than previously achievable. Observations of 3C273 and 3C279 taken in April 2000 with the Coordinated Millimeter VLBI Array have resulted in the first total intensity (Stokes I) and linear polarization VLBI images reported of any source at 86 GHz. These results reveal the 86 GHz electric vector position angles within the jets of 3C273 and 3C279 to be orthogonal to each other, and the core of 3C273 to be unpolarized. If this lack of polarization is due to Faraday depolarization alone, the dispersion in rotation measure is >=90000 rad/m^2 for the core of 3C273.Comment: AASTeX v5.02; 10 pages; 4 figures; accepted for publication in the Astrophysical Journal Letter

The COINS Sample - VLBA Identifications of Compact Symmetric Objects

We present results of multifrequency polarimetric VLBA observations of 34 compact radio sources. The observations are part of a large survey undertaken to identify CSOs Observed in the Northern Sky (COINS). Compact Symmetric Objects (CSOs) are of particular interest in the study of the physics and evolution of active galaxies. Based on VLBI continuum surveys of ~2000 compact radio sources, we have defined a sample of 52 CSOs and CSO candidates. In this paper, we identify 18 previously known CSOs, and introduce 33 new CSO candidates. We present continuum images at several frequencies and, where possible, images of the polarized flux density and spectral index distributions for the 33 new candidates and one previously known but unconfirmed source. We find evidence to support the inclusion of 10 of these condidates into the class of CSOs. Thirteen candidates, including the previously unconfirmed source, have been ruled out. Eleven sources require further investigation. The addition of the 10 new confirmed CSOs increases the size of this class of objects by 50%.Comment: 24 pages, incl 8 figures. Accepted for publication in ApJ. Figure quality degraded in the interests of space, full gzipped PS version also available at http://www.ee.nmt.edu/~apeck/papers

Long discontinuous carbon fibre/polypropylene composites for high volume automotive applications

The volume of fibre reinforced composites is increasing within the automotive industry, as stringent emissions legislation and consumer demands for improved fuel economy are encouraging manufacturers to reduce vehicular mass. Moreover, the falling cost of carbon fibre has meant that these composites are now being considered for semi-structural and structural components for medium-volume (+50,000ppa) applications in Euro Market Segments E and F (Jaguar XF, BMW 7 Series, Mercedes S-Class). The use of thermoplastic matrices with carbon fibre enables cycle times of less than one minute, creating opportunities for high volume manufacture of high specific stiffness components. However, the interfacial adhesion between these materials has been shown to be poor. This thesis seeks to identify whether polypropylene combined with long, discontinuous carbon fibres at high volume fractions, are suitable for high volume, semi-structural applications within the automotive industry. In particular, fibres recovered using two different recycling methods have been considered, as a potential route for reducing future material costs. Interfacial characterisation has been performed using the microbond method to investigate the quality of adhesion between the fibre and matrix, where the effects of sizing removal and introduction of a coupling agent have been considered. Fibre surface topology and chemistry have been examined to interpret data collected from interfacial testing, in addition to fibre strength measurements to assess the validity of the microbond method for high interface strength systems. A tow coating rig has been developed to produce partially pre-impregnated carbon fibre/polypropylene tows. The continuous coated tow has been chopped and processed into random fibre composites using non-isothermal compression moulding, and mechanical properties of the moulded panels have been characterised. The interface strength between sized and desized (pseudo-recycled) carbon fibre and unmodified polypropylene has been found to be poor. A 295% increase in interfacial shear strength (IFSS) is observed with the addition of 2wt.% maleic anhydride to the polypropylene, between the matrix and epoxy-sized carbon fibres. An increase of up to 353% in IFSS is observed for the desized fibres. These improvements can be attributed to chemical bonding as a result of esterification of hydroxyl groups on the carbon fibre surface, with anhydride functionalities of the coupling agent. Additionally, interactions occur between the nitrogen containing groups on the desized fibre surface and the anhydride carbonyl groups in the matrix. Surface roughness is not found to significantly contribute to interface strength. Good interfacial bonding has therefore been observed between polypropylene and sized carbon fibre due to the addition of a coupling agent at 2wt.%, which allows the low cost polymer to be combined with commercially available fibre. Long, discontinuous carbon fibre/polypropylene composites have been characterised in this study at volume fractions that have not previously been reported. Mechanical property characterisation has shown linear increases in stiffness with increasing fibre volume fraction. The specific stiffness of carbon fibre/polypropylene (0.45Vf) is comparable to the carbon fibre/epoxy benchmark. A plateau is observed for both strength and impact strength above volume fractions of 0.25, due to increased void content. The specific strength of the long fibre carbon fibre/polypropylene system can be improved further to a certain extent, by optimising the processing conditions to minimise trapped air

A View through Faraday's Fog 2: Parsec Scale Rotation Measures in 40 AGN

Results from a survey of the parsec scale Faraday rotation measure properties for 40 quasars, radio galaxies and BL Lac objects are presented. Core rotation measures for quasars vary from approximately 500 to several thousand radians per meter squared. Quasar jets have rotation measures which are typically 500 radians per meter squared or less. The cores and jets of the BL Lac objects have rotation measures similar to those found in quasar jets. The jets of radio galaxies exhibit a range of rotation measures from a few hundred radians per meter squared to almost 10,000 radians per meter squared for the jet of M87. Radio galaxy cores are generally depolarized, and only one of four radio galaxies (3C-120) has a detectable rotation measure in the core. Several potential identities for the foreground Faraday screen are considered and we believe the most promising candidate for all the AGN types considered is a screen in close proximity to the jet. This constrains the path length to approximately 10 parsecs, and magnetic field strengths of approximately 1 microGauss can account for the observed rotation measures. For 27 out of 34 quasars and BL Lacs their optically thick cores have good agreement to a lambda squared law. This requires the different tau = 1 surfaces to have the same intrinsic polarization angle independent of frequency and distance from the black hole.Comment: Accepted to the Astrophysical Journal: 71 pages, 40 figure

The Relationship between the UniProt Knowledgebase (UniProtKB) and the IntAct Molecular Interaction Databases

IntAct provides a freely available, open source database system and analysis tools for protein interaction data. All interactions are derived from literature curation or direct user submission and all experimental information relating to binary protein-protein
interactions is entered into the IntAct database by curators, via a web-based editor. Interaction information is added to the SUBUNIT comment and the RP line of the relevant publication within the UniProtKB entry. There may be a single INTERACTION comment present within a UniProtKB entry, which conveys information relevant to binary protein-protein interactions. This is automatically derived from the IntAct database and is updated on a triweekly basis. Interactions can be derived by any appropriate experimental method but must be confirmed by a second interaction if resulting from a single yeast2hybrid experiment. For large-scale experiments, interactions are considered if a high confidence score is assigned by the authors. The INTERACTION line contains a direct link to IntAct that provides detailed information for the experimental support. These lines are not changed manually and any discrepancy is reported to IntAct for updates. There is also a database crossreference line within the UniProtKB entry i.e.: DR IntAct _UniProtKB AC, which directs the user to additional interaction data for that molecule. 
UniProt is supported by grants from the National Institutes of Health, European Commission, Swiss Federal Government and PATRIC BRC.
IntAct is funded by the European Commission under FELICS, contract number 021902 (RII3) within the Research Infrastructure Action of the FP6 "Structuring the European Research Area" Programme