368 research outputs found
A case of effective single-session treatment for attention deficit and learning problems in a routine clinical practice : the value of a transdiagnostic approach to case formulation
This article reports a systematic clinical case study of the psychological assessment and treatment of Daniel (9), a coloured South African boy with a diagnosis of attention deficit hyperactivity disorder (ADHD) (inattentive type). The case is of scientific interest because: (1) there was only a single treatment session, in which contingency management training was delivered to Daniel’s parents and teacher; (2) there was evidence for the effectiveness of the intervention immediately and at two-year follow-up; (3) it documents the transportability to a South African context of an intervention developed by overseas research; (4) it documents the central role of case formulation in the delivery of effective psychological interventions; and (5) although Daniel met the criteria for ADHD, he also displayed symptoms of depression and social anxiety and the case supports the use of a transdiagnostic approach to case formulation. The conscientiousness with which his parents and teachers applied the programme was a major factor in the effectiveness of the intervention, and such rapid impact would not be possible where parents and teachers are unavailable or not co-operative. The publication of systematic case studies such as this one is important for the development of a local evidence-based practice in South Africa
Emissions from Alternate Aviation Fuels and their Environmental Impact
Track II: Transportation and BiofuelsIncludes audio file (19 min.)The anticipated growth in commercial air traffic, rising fuel costs, and an increasing
desire to reduce reliance on fossil fuels produced in politically unstable regions, has
driven research into alternate renewable fuels, either from biomass (Biofuels) or synthesis from coal, natural gas and other renewable feedstocks (Fischer-Tropsch (FT) fuels). Industry and government has recently sponsored (Dec 07, Jan 09) two engine emission tests led in part by the Missouri S&T team. The tests focused on burning alternative and conventional fuels and associated blends in CFM56-type commercial gas turbine engines. The CFM56 engine type is the most common engine in the global commercial fleet powering greater than 70% of the US domestic fleet. The purpose of these emission tests was to quantify any differences in particulate matter (PM) and hazardous air pollutants (HAP) emissions observed between the different fuels, and assess the environmental impacts that may result from these differences. The PM measurements indicate that, especially for the 100% F-T fuel, PM number and mass are diminished at all powers relative to conventional fuels. Some significant differences in hydro-carbon speciation were also observed for the 100% F-T fuel. Differences were less pronounce for the blends. This paper will present a concise summary of the results of these measurement campaigns along with an assessment of any associated environmental impact changes, focusing mainly on airport local air quality and the global atmosphere
Theory of Spin-Resolved Auger-Electron Spectroscopy from Ferromagnetic 3d-Transition Metals
CVV Auger electron spectra are calculated for a multi-band Hubbard model
including correlations among the valence electrons as well as correlations
between core and valence electrons. The interest is focused on the
ferromagnetic 3d-transition metals. The Auger line shape is calculated from a
three-particle Green function. A realistic one-particle input is taken from
tight-binding band-structure calculations. Within a diagrammatic approach we
can distinguish between the \textit{direct} correlations among those electrons
participating in the Auger process and the \textit{indirect} correlations in
the rest system. The indirect correlations are treated within second-order
perturbation theory for the self-energy. The direct correlations are treated
using the valence-valence ladder approximation and the first-order perturbation
theory with respect to valence-valence and core-valence interactions. The
theory is evaluated numerically for ferromagnetic Ni. We discuss the
spin-resolved quasi-particle band structure and the Auger spectra and
investigate the influence of the core hole.Comment: LaTeX, 12 pages, 8 eps figures included, Phys. Rev. B (in press
Issue dimensionality and party politics in turbulent times
We start from the premise that the content of political competition is regularly remade by shifting contexts and by the strategic activity of political actors including parties. But while there are naturally thousands of potential issues on which politics can be contested, there are in practice and for good reasons ways in which structure and limits come to reduce the competition to more cognitively manageable and regularized divisions – in short, to issue dimensions. It is highly timely to return to these questions since, we argue, the social, political and economic turbulence of recent years raises the possibility that the ideological structure to how parties present themselves to voters may be radically shifting. The papers in this special issue, therefore, each tackle an important aspect of the shifting character of the issues that underlie party competition in various European settings. In this article, we provide an overview of the relevant ‘state-of-the-art’ on issue dimensionality and how the subject is situated within the broad framework of understanding party competition
Experimental Characterization of Gas Turbine Emissions at Simulated Flight Altitude Conditions
NASA's Atmospheric Effects of Aviation Project (AEAP) is developing a scientific basis for assessment of the atmospheric impact of subsonic and supersonic aviation. A primary goal is to assist assessments of United Nations scientific organizations and hence, consideration of emissions standards by the International Civil Aviation Organization (ICAO). Engine tests have been conducted at AEDC to fulfill the need of AEAP. The purpose of these tests is to obtain a comprehensive database to be used for supplying critical information to the atmospheric research community. It includes: (1) simulated sea-level-static test data as well as simulated altitude data; and (2) intrusive (extractive probe) data as well as non-intrusive (optical techniques) data. A commercial-type bypass engine with aviation fuel was used in this test series. The test matrix was set by parametrically selecting the temperature, pressure, and flow rate at sea-level-static and different altitudes to obtain a parametric set of data
PM Emission From a Commercial Jet Engine -- Project APEX
Project APEX (Aircraft Particle Emissions eXperiment) was a multi-agency commercial aircraft emission characterization and technology demonstration experiment. Its objective was to characterize particle and trace gas precursor species in the emissions from a NASA DC-8 aircraft with General Electric CFM56-2C1 engines at the engine exit plane as well as selected down stream locations. This was to advance the understanding of particle emissions and their evolution in the atmosphere from a current in-service turbofan engine. The test was conducted at the NASA Dryden Flight Research Center at Edwards Air Force Base California during April 15-30, 2004. Participants included the National Aeronautics and Space Administration, Environmental Protection Agency, Federal Aviation Administration, Department of Defense, the aviation industry (General Electric, Pratt and Whitney, and Boeing), and the research community (Aerodyne Research Inc., Massachusetts Institute of Technology, Process Metrix, University of California-Riverside, and University of Missouri-Rolla)
Influence of Ambient Temperature on the PM Emissions from a Gas Turbine Engine
During Project AAFEX, PM emissions measurements were conducted on a CFM56-2C1 gas turbine engine in January 2009 in Palmdale CA. The engine was mounted on a NASA DC-8 aircraft, which was parked on the runway, and emission samples were extracted at the engine exit plane (1m), in the near field (30m), and in the advected plume (145m). The engine was operated at several power levels, and burned several fuels: JP-8, a Fischer-Tropsch fuel derived from natural gas (FT1), and a second Fischer-Tropsch fuel derived from gasified coal (FT2). In addition to these fuels, 50:50 blends of the Fischer-Tropsch fuels and JP-8 were also studied. Wide variations in ambient temperature, especially between early morning and late afternoon were experienced during the campaign. This report summarizes and describes the results of AAFEX, in terms of the influence of ambient temperature on total PM emissions at the exit plane of a CFM56-2C1 engine
Addendum to the CLOUD proposal
This report is the first of two addenda to the CLOUD proposal at CERN (physics/0104048), which aims to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. The document provides further details on the detector design, scientific motivation and experimental programme
CLOUD: an atmospheric research facility at CERN
This report is the second of two addenda to the CLOUD proposal at CERN (physics/0104048), which aims to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. The document places CLOUD in the framework of a CERN facility for atmospheric research, and provides further details on the particle beam requirements
In Situ Measurement of the Aerosol Size Distribution in Stratospheric Solid Rocket Motor Exhaust Plumes
The concentration and size distribution of aerosol in the stratospheric exhaust plumes of two Space Shuttle rockets and one Titan IV rocket were measured using a two component aerosol sampling system carried aboard a WB‐57F aircraft. Aerosol size distribution in the 0.01 µm to 4 µm diameter size range was measured using a two component sampling system. The measured distributions display a trimodal form with modes near 0.005 µm, 0.09 µm, and 2.03 µm and are used to infer the relative mass fractionation among the three modes. While the smallest mode has been estimated to contain as much as 10% of the total mass of SRM exhaust alumina, we find show that the smallest mode contains less than 0.05% of the alumina mass. This fraction is so small so as to significantly reduce the likelihood that heterogeneous reactions on the SRM alumina surfaces could produce a significant global impact on stratospheric chemistry
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