27,984 research outputs found

    A Multilateral Approach to Bridging the Global Skills Gap

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    [Excerpt] In 2012, McKinsey & Company forecasted a troubling outlook on the labor market through the year 2020. The report highlighted three talent shortages across the globe: nearly 40 million too few college educated workers in the global labor market; a 45 million shortfall of workers with secondary and vocational education in developing countries; and up to 95 million workers that lack the skills needed for employment in advanced economies. This global crisis is known as the skills gap. It impacts nearly every industry, job and employer. Simply put, critical talent supply will fail to meet employment demand in the coming decade. Such an imbalance can be crippling to economic progress, put strain on governments, and leave millions unemploye

    Laschelles\u27 Pontifex maximus: A short history of the popes (book review)

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    Sea floor swells and mantle plumes

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    Most of the intraplate oceanic hot spots are located on the crest of broad topographic swells in the sea floor. These swells have Gaussian shaped profiles, with up to 1.6 km of relief and half widths of 200 to 300 km. Swells are accompanied by positive geoid height anomalies with amplitudes of 6 to 8 m. In the Atlantic and Pacific basins swells cover an area equal to 10% of the Earth's surface. Next to boundary layer contraction, swells are the most important cause of uplift and subsidence in oceanic lithosphere. Calculation of buoyancy supported topography and geoid height were combined with uplift data from laboratory experiments to assess whether sea floor swell can be produced by mantle plumes. The critical constraints are: (1) swell topographic profiles; (2) geoid height/topographic height ratios; and (3) uplift rates, estimated to be 0.2 km/ma

    Dynamos with weakly convecting outer layers: implications for core-mantle boundary interaction

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    Convection in the Earth's core is driven much harder at the bottom than the top. This is partly because the adiabatic gradient steepens towards the top, partly because the spherical geometry means the area involved increases towards the top, and partly because compositional convection is driven by light material released at the lower boundary and remixed uniformly throughout the outer core, providing a volumetric sink of buoyancy. We have therefore investigated dynamo action of thermal convection in a Boussinesq fluid contained within a rotating spherical shell driven by a combination of bottom and internal heating or cooling. We first apply a homogeneous temperature on the outer boundary in order to explore the effects of heat sinks on dynamo action; we then impose an inhomogeneous temperature proportional to a single spherical harmonic Y2² in order to explore core-mantle interactions. With homogeneous boundary conditions and moderate Rayleigh numbers, a heat sink reduces the generated magnetic field appreciably; the magnetic Reynolds number remains high because the dominant toroidal component of flow is not reduced significantly. The dipolar structure of the field becomes more pronounced as found by other authors. Increasing the Rayleigh number yields a regime in which convection inside the tangent cylinder is strongly affected by the magnetic field. With inhomogeneous boundary conditions, a heat sink promotes boundary effects and locking of the magnetic field to boundary anomalies. We show that boundary locking is inhibited by advection of heat in the outer regions. With uniform heating, the boundary effects are only significant at low Rayleigh numbers, when dynamo action is only possible for artificially low magnetic diffusivity. With heat sinks, the boundary effects remain significant at higher Rayleigh numbers provided the convection remains weak or the fluid is stably stratified at the top. Dynamo action is driven by vigorous convection at depth while boundary thermal anomalies dominate in the upper regions. This is a likely regime for the Earth's core

    Experiences of mental illness, treatment and recovery in schizophrenia. An existential-phenomenological exploration

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    This study explores in depth the narratives and experience of recovery from a convenience sample of seven participants with a schizophrenia diagnosis, but now remitted (Andreasen et al, 2005). Three lifeworlds (phases) emerged using hermeneutic phenomenology: (A) Losing existential grounding; (B) Being-within-the-system (i.e. hospitalised); and (C) Outside schizophrenia. Outside has a double meaning as it both emerges from the narratives and also is an important base for existential exploration: what else needs to happen except psychiatry? Each lifeworld had a different meaning and different behaviours connected to it. Two necessary transitions were identified: First, accepting help; and second, an existential construction or re- construction depending on where in your life course you become affected. Psychotherapy was useful, but not necessary for remission and recovery

    Heat transfer in a compact tubular heat exchanger with helium gas at 3.5 MPa

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    A compact heat exchanger was constructed consisting of circular tubes in parallel brazed to a grooved base plate. This tube specimen heat exchanger was tested in an apparatus which radiatively heated the specimen on one side at a heat flux of up to 54 W/sq cm, and cooled the specimen with helium gas at 3.5 MPa and Reynolds numbers of 3000 to 35,000. The measured friction factor of the tube specimen was lower than that of a circular tube with fully developed turbulent flow, although the uncertainty was high due to entrance and exit losses. The measured Nusselt number, when modified to account for differences in fluid properties between the wall and the cooling fluid, agreed with past correlations for fully developed turbulent flow in circular tubes
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