Imaging the Molecular Gas in A z=3.9 Quasar Host Galaxy at 0\farcs3 Resolution: A Central, Sub-Kilparsex Scale Star Formation Reservoir in APM 08279+5255

We have mapped the molecular gas content in the host galaxy of the strongly lensed high-redshift quasar APM 08279+5255 (z = 3.911) with the Very Large Array at 0\farcs3 resolution. The CO(J = 1➝0) emission is clearly resolved in our maps. The CO(J = 1➝0) line luminosity derived from these maps is in good agreement with a previous single-dish measurement. In contrast to previous interferometer-based studies, we find that the full molecular gas reservoir is situated in two compact peaks separated by ≲0\farcs4. Our observations reveal, for the first time, that the emission from cold molecular gas is virtually co-spatial with the optical/near-infrared continuum emission of the central active galactic nucleus (AGN) in this source. This striking similarity in morphology indicates that the molecular gas is situated in a compact region close to the AGN. Based on the high-resolution CO maps, we present a revised model for the gravitational lensing in this system, which indicates that the molecular gas emission is magnified by only a factor of 4 (in contrast to previously suggested factors of 100). This model suggests that the CO is situated in a circumnuclear disk of ~550 pc radius that is possibly seen at an inclination of ≲25°, i.e., relatively close to face-on. From the CO luminosity, we derive a molecular gas mass of Mgas = 1.3x10^11 M☉ for this galaxy. From the CO structure and linewidth, we derive a dynamical mass of M dyn sin^2 i = 4.0x10^10 M☉. Based on a revised mass estimate for the central black hole of Mbh = 2.3x10^10 M☉ and the results of our molecular line study, we find that the mass of the stellar bulge of APM 08279+5255 falls short of the local M BH-σbulge relationship of nearby galaxies by more than an order of magnitude, lending support to recent suggestions that this relation may evolve with cosmic time and/or change toward the high-mass end

Trajectory generation for cooperating robots

Includes bibliographical references (page 302).This paper derives a formulation for on-line trajectory generation for two robots cooperating to perform an assembly task. The two robots are treated as a single redundant system. A Jacobian is formulated that relates the joint rates of the entire system to the relative motion of one of the hands with respect to the other. The minimum norm solution of this relative Jacobian equation results in a set of joint rates which perform the cooperative task. In addition to the cooperative task, secondary goals, which include obstacle and joint limit avoidance, are specified using velocities in the null space of the relative Jacobian. This formulation also allows the robots to be controlled in parallel on independent tasks

A Molecular Einstein Ring at z=4.12: Imaging the Dynamics of a Quasar Host Galaxy Through a Cosmic Lens

We present high-resolution (0.3") Very Large Array (VLA) imaging of the molecular gas in the host galaxy of the high redshift quasar PSS J2322+1944 (z=4.12). These observations confirm that the molecular gas (CO) in the host galaxy of this quasar is lensed into a full Einstein ring, and reveal the internal dynamics of the molecular gas in this system. The ring has a diameter of ~1.5", and thus is sampled over ~20 resolution elements by our observations. Through a model-based lens inversion, we recover the velocity gradient of the molecular reservoir in the quasar host galaxy of PSS J2322+1944. The Einstein ring lens configuration enables us to zoom in on the emission and to resolve scales down to ~1 kpc. From the model-reconstructed source, we find that the molecular gas is distributed on a scale of 5 kpc, and has a total mass of M(H2)=1.7 x 10^10 M_sun. A basic estimate of the dynamical mass gives M_dyn = 4.4 x 10^10 (sin i)^-2 M_sun, that is, only ~2.5 times the molecular gas mass, and ~30 times the black hole mass (assuming that the dynamical structure is highly inclined). The lens configuration also allows us to tie the optical emission to the molecular gas emission, which suggests that the active galactic nucleus (AGN) does reside within, but not close to the center of the molecular reservoir. Together with the (at least partially) disturbed structure of the CO, this suggests that the system is interacting. Such an interaction, possibly caused by a major `wet' merger, may be responsible for both feeding the quasar and fueling the massive starburst of 680 M_sun/yr in this system, in agreement with recently suggested scenarios of quasar activity and galaxy assembly in the early universe.Comment: 9 pages, 7 figures, to appear in ApJ (accepted June 27, 2008

Competitor analysis of functional group H-bond donor and acceptor properties using the Cambridge Structural Database.

Intermolecular interactions found in the Cambridge Structural Database (CSD) are analysed as the outcomes of competitions between the different functional groups that are present in each structure: the most energetically favourable interactions are expected to win more often than weaker interactions. Tracking winners and losers through each crystal structure in the CSD provides data that can be analysed using paired comparison algorithms to rank functional group H-bonding properties based on how frequently they outcompete other functional groups in the crystal. This treatment is superior to simple statistical analyses of whether functional groups H-bond or not, because the distribution of H-bond donors and acceptors in the structures of the molecules found in the CSD is non-random. Most organic molecules contain more acceptors than donors, so that all H-bond donors are almost always H-bonded in all crystal structures, and most acceptors are not. The rankings of H-bond acceptors obtained by applying the TrueSkill paired comparison algorithm to the CSD agree well with the corresponding experimentally determined solution phase H-bond acceptor parameters β, but there is insufficient data to corroborate H-bond donor rankings calculated in the same way. The method is used to make predictions of the H-bond acceptor properties of functional groups for which solution phase measurements are not available.Engineering and Physical Sciences Research Council, Cambridge Crystallographic Data Centr

Driven Pile Capacity in Clay and Drilled Shaft Capacity in Rock from Field Load Tests

In this study, two case histories of deep foundations are discussed, including driven piles and drilled shafts. The first case history is an assessment of driven pile capacity in clay. As part of selecting the deep foundation system, steel pipe, concrete, and timber piles were driven at the site. Static compression and uplift load tests were performed on the concrete and timber piles, while only static compression tests were performed on the steel pipe piles. Measured pile capacities from the static load tests were compared to predicted pile capacities, which were obtained from empirical design methods employing laboratory and in-situ test results. The data demonstrate that the traditional alpha method results in somewhat conservative predictions for the test piles, regardless of whether the values of undrained shear strength (su) are obtained directly from the unconfined compression (UC) test or are inferred from a correlation with the CPTU as equivalent direct simple shear (DSS) values of su. The second case study involves an evaluation of the axial and lateral capacities of drilled shafts in rock to support a concrete gated dam. The test drilled shafts were step-tapered from 5.5-ft diameter through the soil zone to 5-ft diameter in the rock socket. Axial and lateral load tests were performed on drilled shafts embedded in soft to medium hard clayey shale and claystone overlain by granular alluvium. The data demonstrate that longstanding methods of determining ultimate side resistance are conservative relative to the measured values, as are customary presumptive values, but that predictions using one evolving method can be unconservative in the absence of field verification. In addition, the shafts performed satisfactorily under the applied design load, exhibiting minimal lateral deflection within the rock socket

αCP binding to a cytosine-rich subset of polypyrimidine tracts drives a novel pathway of cassette exon splicing in the mammalian transcriptome.

Alternative splicing (AS) is a robust generator of mammalian transcriptome complexity. Splice site specification is controlled by interactions of cis-acting determinants on a transcript with specific RNA binding proteins. These interactions are frequently localized to the intronic U-rich polypyrimidine tracts (PPT) located 5' to the majority of splice acceptor junctions. αCPs (also referred to as polyC-binding proteins (PCBPs) and hnRNPEs) comprise a subset of KH-domain proteins with high affinity and specificity for C-rich polypyrimidine motifs. Here, we demonstrate that αCPs promote the splicing of a defined subset of cassette exons via binding to a C-rich subset of polypyrimidine tracts located 5' to the αCP-enhanced exonic segments. This enhancement of splice acceptor activity is linked to interactions of αCPs with the U2 snRNP complex and may be mediated by cooperative interactions with the canonical polypyrimidine tract binding protein, U2AF65. Analysis of αCP-targeted exons predicts a substantial impact on fundamental cell functions. These findings lead us to conclude that the αCPs play a direct and global role in modulating the splicing activity and inclusion of an array of cassette exons, thus driving a novel pathway of splice site regulation within the mammalian transcriptome

The short-form revised Eysenck personality Questionnaire (EPQ-S): A German edition

A sample of 331 undergraduate students in Germany completed the German translation of the short form Revised Eysenck Personality Questionnaire (EPQR-S; Eysenck, Eysenck, & Barrett,1985). The findings support the psychometric properties of the extraversion, neuroticism and lie scales. The psychoticism scale, however, was found to be less satisfactory