2,985 research outputs found

    The offshore services value chain : developing countries and the crisis

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    This paper analyzes the recent evolution and impact of the global economic crisis on the offshore services industry. Using a global value chains framework, the authors classify the offshore services sector in a comprehensive set of general and industry-specific activities that correspond to different segments and stages in the value-adding process for services. Through an analysis of the impact of the economic crisis on the industry, a small decline in demand was found; however this did not cause any structural changes in the market. The crisis has created two opposing effects: general contraction of demand by existing customers due to the recession; and, at the same time, a substitution effect by which new services are being moved from developed countries to emerging economies in search of cost reduction. The paper concludes that the offshore services industry will continue to offer growth opportunities for developing countries not only among existing market players, but also a range of new countries. The industry has the potential to become an important source for employment and economic growth around the globe.ICT Policy and Strategies,E-Business,Water and Industry,Housing&Human Habitats,Public Sector Corruption&Anticorruption Measures

    Multiplicity of nuclear dust lanes and dust lane shocks in the Milky Way bar

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    Aims: We show the existence of a small family of inner-galaxy dust lanes and dust lane standing shocks beyond the two major ones that were previously known to exist Methods: We analyze images of CO emission in the inner regions of the Galaxy Results: The peculiar kinematics of the major dust lane features are repeated in several other distinct instances at l > 0deg, in one case at a contrary location 100 pc above the galactic equator at l > 3degr at the upper extremity of Clump 2. Like the previously-known dust lanes, these new examples are alsoassociated with localized, exceptionally broad line profiles believed to be characteristic of the shredding of neutral gas at the standing dust lane shocks. Conclusions: There may be secondary dust lane and standing shocks in the Milky Way bulge. The vertical structure provides a temporal sequence for understanding the secular evolution of gas flow in the bar

    Medial temporal lobe activation during encoding and retrieval of novel face-name pairs

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    The human medial temporal lobe (MTL) is known to be involved in declarative memory, yet the exact contributions of the various MTL structures are not well understood. In particular, the data as to whether the hippocampal region is preferentially involved in the encoding and/or retrieval of associative memory have not allowed for a consensus concerning its specific role. To investigate the role of the hippocampal region and the nearby MTL cortical areas in encoding and retrieval of associative versus non-associative memories, we used functional magnetic resonance imaging (fMRI) to measure brain activity during learning and later recognition testing of novel face-name pairs. We show that there is greater activity for successful encoding of associative information than for non-associative information in the right hippocampal region, as well as in the left amygdala and right parahippocampal cortex. Activity for retrieval of associative information was greater than for non-associative information in the right hippocampal region also, as well as in the left perirhinal cortex, right entorhinal cortex, and right parahippocampal cortex. The implications of these data for a clear functional distinction between the hippocampal region and the MTL cortical structures are discussed. © 2004 Wiley-Liss, Inc

    Coupling the dynamics and the molecular chemistry in the Galactic center

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    The physical conditions of the Galactic center (GC) clouds moving with non-circular velocities are not well-known. We have studied the physical conditions of these clouds with the aim of better understanding the origin of the outstanding physical conditions of the GC molecular gas and the possible effect of the large scale dynamics on these physical conditions.Using published CO(1-0) data, we have selected a set of clouds belonging to all the kinematical components seen in the longitude-velocity diagram of the GC. We have done a survey of dense gas in all the components using the J=2-1 lines of CS and SiO as tracers of high density gas and shock chemistry. We have detected CS and SiO emission in all the kinematical components. The gas density and the SiO abundance of the clouds in non-circular orbits are similar those in the nuclear ring (GCR). Therefore, in all the kinematical components there are dense clouds that can withstand the tidal shear. However, there is no evidence of star formation outside the GCR. The high relative velocity and shear expected in the dust-lanes along the bar major axis could inhibit the star formation process, as observed in other galaxies. The high SiO abundances derived in the non-circular velocity clouds are likely due to the large-scale shocks that created the dust lanesComment: One figure as an independent PDF file. Accepted by A&

    The AST/RO Survey of the Galactic Center Region. I. The Inner 3 Degrees

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    We present fully-sampled maps of 461 GHz CO (4-3), 807 GHz CO (7-6), and 492 GHz [CI] (3P1-3P0) emission from the inner 3 degrees of the Galactic Center region taken with the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) in 2001--2002. The data cover -1.3 < l < 2, -0.3 < b < 0.2 with 0.5 arcmin spacing, resulting in spectra in 3 transitions at over 24,000 positions on the sky. The CO (4-3) emission is found to be essentially coextensive with lower-J transitions of CO. The CO (7-6) emission is spatially confined to a far smaller region than the lower-J CO lines. The [CI] (3P1-3P0) emission has a spatial extent similar to the low-J CO emission, but is more diffuse. Bright CO (7-6) emission is detected in the well-known Galactic Center clouds Sgr A and Sgr B. We also detect CO (4-3) and CO (7-6) absorption from spiral arms in the galactic disk at velocities near 0 km s^-1 along the line of sight to the Galactic Center. Analyzing our CO (7-6) and CO (4-3) data in conjunction with J = 1 - 0 12CO and 13CO data previously observed with the Bell Laboratories 7-m antenna, we apply a Large Velocity Gradient (LVG) model to estimate the kinetic temperature and density of molecular gas in the inner 200 pc of the Galactic Center region. We show maps of the derived distribution of gas density and kinetic temperature as a function of position and velocity for the entire region. Kinetic temperature was found to decrease from relatively high values (>70K) at cloud edges to low values (<50K) in the interiors. Typical gas pressures in the Galactic Center gas are n(H_2) T_kin approx 10^5.2 K cm^-3. We also present an (l,b) map of molecular hydrogen column density derived from our LVG results.Comment: 41 pages, 29 figures reduced to low resolution for astro-ph, for high resolution figures please go to http://cfa-www.harvard.edu/ASTRO/galcen_1.pdf this version incorporates changes due to accepted erratum (to appear in ApJS 153

    Non-coding regions of nuclear-DNA-encoded mitochondrial genes and intergenic sequences are targeted by autoantibodies in breast cancer

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    Autoantibodies against mitochondrial-derived antigens play a key role in chronic tissue inflammation in autoimmune disorders and cancers. Here, we identify autoreactive nuclear genomic DNA (nDNA)-encoded mitochondrial gene products (GAPDH, PKM2, GSTP1, SPATA5, MFF, TSPOAP1, PHB2, COA4, and HAGH) recognized by breast cancer (BC) patients\u27 sera as nonself, supporting a direct relationship of mitochondrial autoimmunity to breast carcinogenesis. Autoreactivity of multiple nDNA-encoded mitochondrial gene products was mapped to protein-coding regions, 3\u27 untranslated regions (UTRs), as well as introns. In addition, autoantibodies in BC sera targeted intergenic sequences that may be parts of long non-coding RNA (lncRNA) genes, including LINC02381 and other putative lncRNA neighbors of the protein-coding genes ERCC4, CXCL13, SOX3, PCDH1, EDDM3B, and GRB2. Increasing evidence indicates that lncRNAs play a key role in carcinogenesis. Consistent with this, our findings suggest that lncRNAs, as well as mRNAs of nDNA-encoded mitochondrial genes, mechanistically contribute to BC progression. This work supports a new paradigm of breast carcinogenesis based on a globally dysfunctional genome with altered function of multiple mitochondrial and non-mitochondrial oncogenic pathways caused by the effects of autoreactivity-induced dysregulation of multiple genes and their products. This autoimmunity-based model of carcinogenesis will open novel avenues for BC treatment

    Candida dubliniensis Meningitis as Delayed Sequela of Treated C. dubliniensis Fungemia

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    We present a case of Candida dubliniensis meningitis that developed 2 months after apparently successful treatment of an episode of C. dubliniensis candidemia in a heart-lung transplant recipient in Australia. This case highlights the importance of follow-up in patients with candidemia or disseminated infection, especially in immunosuppressed patients

    A general model of resonance capture in planetary systems: First and second order resonances

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    Mean motion resonances are a common feature of both our own Solar System and of extrasolar planetary systems. Bodies can be trapped in resonance when their orbital semi-major axes change, for instance when they migrate through a protoplanetary disc. We use a Hamiltonian model to thoroughly investigate the capture behaviour for first and second order resonances. Using this method, all resonances of the same order can be described by one equation, with applications to specific resonances by appropriate scaling. We focus on the limit where one body is a massless test particle and the other a massive planet. We quantify how the the probability of capture into a resonance depends on the relative migration rate of the planet and particle, and the particle's eccentricity. Resonant capture fails for high migration rates, and has decreasing probability for higher eccentricities. More massive planets can capture particles at higher eccentricities and migration rates. We also calculate libration amplitudes and the offset of the libration centres for captured particles, and the change in eccentricity if capture does not occur. Libration amplitudes are higher for larger initial eccentricity. The model allows for a complete description of a particle's behaviour as it successively encounters several resonances. We discuss implications for several scenarios: (i) Planet migration through gas discs trapping other planets or planetesimals in resonances. (ii) Planet migration through a debris disc. (iii) Dust migration through PR drag. The Hamiltonian model will allow quick interpretation of the resonant properties of extrasolar planets and Kuiper Belt Objects, and will allow synthetic images of debris disc structures to be quickly generated, which will be useful for predicting and interpreting disc images made with ALMA, Darwin/TPF or similar missions. [Abridged]Comment: 19 pages, 14 figures; accepted to MNRA

    Sistemas inteligentes distribuidos para resolver problemas de optimización

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    En la comunidad científica se observa una importante tendencia por resolver problemas de optimización, a través de la utilización de algoritmos tanto exactos como heurísticos. Esto se debe a que nos enfrentamos con nuevos problemas ingenieriles y recursos computacionales, tales como tipos de máquinas, redes y entornos como Internet. Los problemas de optimización más atacados son los de: asignación de recursos, balance en la línea de ensamblaje, planificación y programación (scheduling), corte y empaquetado de una o varias dimensiones (cutting/packing), etc. Y ellos cuentan con la particularidad de cubrir una importante cantidad de problemas ingenieriles y productivos en nuestra región, y su aplicación puede producir un favorable impacto económico. El objetivo principal de esta línea de investigación comprende el diseño y desarrollo de algoritmos en entornos distribuidos para la resolución de problemas de creciente dificultad (NP-duros), utilizando técnicas heurísticas y exactas tales como el recocido simulado, búsqueda tabú, búsqueda local y sus posibles hibridaciones, como así también diferentes técnicas relacionadas con los algoritmos evolutivos. De estos algoritmos se analizará la relación eficacia/eficiencia para obtener patrones del comportamiento de los mismos. La implementación en entornos distribuidos se realizará para que a través del paralelismo de las operaciones se puedan alcanzar soluciones de alta calidad rápidamente.Eje: Inteligencia artificialRed de Universidades con Carreras en Informática (RedUNCI

    Nuclear Bar Catalyzed Star Formation: 13^CO, C18^O and Molecular Gas Properties in the Nucleus of Maffei 2

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    (Abridged) We present resolution maps of CO, its isotopologues, and HCN from in the center of Maffei 2. The J=1-0 rotational lines of 12^CO, 13^CO, C18^O and HCN, and the J=2-1 lines of 13^CO and C18^O were observed with the OVRO and BIMA arrays. The 2-1/1-0 line ratios of the isotopologues constrain the bulk of the molecular gas to originate in low excitation, subthermal gas. From LVG modeling, we infer that the central GMCs have n(H_2) ~10^2.75 cm^-3 and T_k ~ 30 K. Continuum emission at 3.4 mm, 2.7 mm and 1.4 mm was mapped to determine the distribution and amount of HII regions and dust. Column densities derived from C18^O and 1.4 mm dust continuum fluxes indicate the CO conversion factor in the center of Maffei 2 is lower than Galactic by factors of ~2-4. Gas morphology and the clear ``parallelogram'' in the Position-Velocity diagram shows that molecular gas orbits within the potential of a nuclear (~220 pc) bar. The nuclear bar is distinct from the bar that governs the large scale morphology of Maffei 2. Giant molecular clouds in the nucleus are nonspherical and have large linewidths. Dense gas and star formation are concentrated at the sites of the x_1-x_2 orbit intersections of the nuclear bar, suggesting that the starburst is dynamically triggered.Comment: 50 pages, 14 figures, accepted for publication in Ap
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