3,193 research outputs found

    Ultrasound by emergency physicians to detect abdominal aortic aneurysms: a UK case series

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    Early identification of abdominal aortic aneurysms in some patients can be difficult and the diagnosis is missed in up to 30% of patients. Ultrasound cannot be used to identify a leak, but the presence of an aneurysm in an unstable patient is conclusive. With minimal training emergency physicians can easily identify the aorta and thus in the early phase of resuscitation an aneurysm can be confidently excluded. The purpose of the examination is not to delineate the extent of the aneurysm, but to identify those patients that will need emergency surgery. A series of patients presented to the department in an unstable condition with equivocal abdominal signs. An ultrasound scan in the resuscitation room by members of the emergency department revealed an aneurysm, which was enough to convince the vascular surgeons to take the patient straight to theatre with good results. In patients who are stable, computed tomography will continue to be used to evaluate the extent of the aneurysm and identify a leak

    A Unified Treatment of Horizontal Direct Investment, Vertical Direct Investment, and the Pattern of Trade in Goods and Services

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    This paper contributes to research endogenizing multinational firms in general-equilibrium trade models. We attempt to integrate separate contributions on horizontal multinationals which produce the same final product in multiple locations, with work on vertical multinationals, which geographically fragment production by stages. Previously derived results now emerge as special cases of a more general model. Vertical multinationals dominate when countries are very different in relative factor endowments. Horizontal multinationals dominate when the countries are similar in size and in relative endowments, and trade costs are moderate to high. In some cases, foreign investment or trade liberalization leads to a reversal in the direction of trade. Investment liberalization can also lead to an increase in the volume of trade and produces a strong tendency toward factor-price equalization. Thus direct investment can be a complement to trade in both a volume-of-trade sense and in a welfare sense.

    Problems with oral formulations prescribed to children: a focus group study of healthcare professionals

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    Background There is evidence to suggest that adherence with prescribed medication is lower amongst adolescents and children than in adults. Medication adherence rates between 11 and 93 % in paediatric patients have been reported. More research needs to be carried out in order to understand why medicines adherence is low and how adherence can be improved in children with long-term conditions. Personal communication with paediatricians in secondary care has highlighted that problems are most likely to be encountered by parents, carers, nurses and children themselves when administering medicines for prevalent long-term childhood conditions. Objective To explore problems with oral medicines prescribed to paediatric patients from the perspectives of medical practitioners, pharmacists and nurses. Setting Two NHS trusts in the West Midlands, UK. Methods Four focus groups (FG) were conducted. Five nurses, eight medical practitioners and six pharmacists participated in focus groups. The themes explored were problems experienced when prescribing, dispensing and administering oral medicines for children. Main outcome measure Themes evolving from Healthcare professionals reports on problems with administering medicines to paediatric patients. Results Two main themes: sensory and non-sensory emerged from the data. Included within these were taste, texture, colour, smell, size, swallowing, quantity, volume and manipulation with food. Taste was the most commonly reported barrier to medicines administration. Texture was reported to be a significant problem for the learning disability population. Medicines manipulation techniques were revealed across the groups, yet there was limited knowledge regarding the evidence base for such activity. Problems surrounding the supply of Specials medicines were discussed in-depth by the pharmacists. Conclusion Organoleptic and physical properties of medicines are key barriers to medicines administration. A robust scientific evidence-based approach is warranted to inform standardised protocols guiding healthcare professionals to support safe and effective medicines manipulation across all settings. Pharmacists’ knowledge of Specials medicines needs to be recognised as a valuable resource for doctors. Findings of this study should help to optimise paediatric prescribing and direct future formulation work

    Atomistic mechanisms for the ordered growth of Co nano-dots on Au(788): comparison of VT-STM experiments and multi-scaled calculations

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    Hetero-epitaxial growth on a strain-relief vicinal patterned substrate has revealed unprecedented 2D long range ordered growth of uniform cobalt nanostructures. The morphology of a Co sub-monolayer deposit on a Au(111) reconstructed vicinal surface is analyzed by Variable Temperature Scanning Tunneling Microscopy (VT-STM) experiments. A rectangular array of nano-dots (3.8 nm x 7.2 nm) is found for a particularly large deposit temperature range lying from 60 K to 300 K. Although the nanodot lattice is stable at room temperature, this paper focus on the early stage of ordered nucleation and growth at temperatures between 35 K and 480 K. The atomistic mechanisms leading to the nanodots array are elucidated by comparing statistical analysis of VT-STM images with multi-scaled numerical calculations combining both Molecular Dynamics for the quantitative determination of the activation energies for the atomic motion and the Kinetic Monte Carlo method for the simulations of the mesoscopic time and scale evolution of the Co submonolayer

    Evolution of unoccupied resonance during the synthesis of a silver dimer on Ag(111)

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    Silver dimers were fabricated on Ag(111) by single-atom manipulation using the tip of a cryogenic scanning tunnelling microscope. An unoccupied electronic resonance was observed to shift toward the Fermi level with decreasing atom-atom distance as monitored by spatially resolved scanning tunnelling spectroscopy. Density functional calculations were used to analyse the experimental observations and revealed that the coupling between the adsorbed atoms is predominantly direct rather than indirect via the Ag(111) substrate.Comment: 9 pages, 3 figure

    Island size distributions in submonolayer growth: successful prediction by mean field theory with coverage dependent capture numbers

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    We show that mean-field rate equations for submonolayer growth can successfully predict island size distributions in the pre-coalescence regime if the full dependence of capture numbers on both the island size and the coverage is taken into account. This is demonstrated by extensive Kinetic Monte Carlo simulations for a growth kinetics with hit and stick aggregation. A detailed analysis of the capture numbers reveals a nonlinear dependence on the island size for small islands. This nonlinearity turns out to be crucial for the successful prediction of the island size distribution and renders an analytical treatment based on a continuum limit of the mean-field rate equations difficult.Comment: 4 pages, 4 figue

    A Unified Treatment of Horizontal Direct Investment, Vertical Direct Investment, and the Pattern of Trade in Goods and Services

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    This paper contributes to research endogenizing multinational firms in general-equilibrium trade models. We attempt to integrate separate contributions on horizontal multinationals which produce the same final product in multiple locations, with work on vertical multinationals, which geographically fragment production by stages. Previously derived results now emerge as special cases of a more general model. Vertical multinationals dominate when countries are very different in relative factor endowments. Horizontal multinationals dominate when the countries are similar in size and in relative endowments, and trade costs are moderate to high. In some cases, foreign investment or trade liberalization leads to a reversal in the direction of trade. Investment liberalization can also lead to an increase in the volume of trade and produces a strong tendency toward factor-price equalization. Thus direct investment can be a complement to trade in both a volume-of-trade sense and in a welfare sense

    Island Density in Homoepitaxial Growth:Improved Monte Carlo Results

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    We reexamine the density of two dimensional islands in the submonolayer regime of a homoepitaxially growing surface using the coarse grained Monte Carlo simulation with random sequential updating rather than parallel updating. It turns out that the power law dependence of the density of islands on the deposition rate agrees much better with the theoretical prediction than previous data obtained by other methods if random sequential instead of parallel updating is used.Comment: Latex with 2 PS figure file

    Nonequilibrium phase transitions in models of adsorption and desorption

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    The nonequilibrium phase transition in a system of diffusing, coagulating particles in the presence of a steady input and evaporation of particles is studied. The system undergoes a transition from a phase in which the average number of particles is finite to one in which it grows linearly in time. The exponents characterizing the mass distribution near the critical point are calculated in all dimensions.Comment: 10 pages, 2 figures (To appear in Phys. Rev. E
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