7,189 research outputs found

    Diffusion and convection of gaseous and fine particulate from a chimney

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    Particle dispersion from a high chimney is considered and an expression for the subsequent concentration of the particulate deposited on the ground is derived. We consider the general case wherein the effects of both diffusion and convection on the steady state ground concentration of particulate are incorporated. Two key parameters emerge from this analysis: the ratio of diffusion to convection and the nondimensionalised surface mass transfer rate. We also solve the inverse problem of recovering these two parameters given the boundary concentration profile and provide an estimate of the concentration flux above the chimney stack

    Dynamic performance of detuned ridge waveguide AlInGaAs distributed feedback laser diodes

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    The dynamic behavior of AlInGaAs ridge waveguide distributed feedback lasers is reported in this work covering five detuned wavelengths between 1291 nm and 1326 nm for a laser active layer optical peak gain design centered at 1310 nm at room temperature. The detuning is achieved by modifying the laser grating pitch that performs the mode selection within the laser cavity simultaneously across a single processed wafer. The dynamic behavior is evaluated using the resonance frequencies of the detuned lasers measured at a range of injection currents for heatsink temperatures of 25°C and 85°C. The results confirm that a speed improvement can be achieved at 25°C by detuning the laser to shorter wavelengths. However, the results also show that a lower direct modulation bandwidth at 85°C makes the shorter wavelength design less attractive. For communications applications such as 10 Gbps uncooled operation, this trade-off between detuning and modulation bandwidth imply an optimum around −2 nm to +8 nm detuning (measured at 25°C)

    Improving continence services for older people from the service-providers' perspective: a qualitative interview study

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    This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial.Objective To examine in depth the views and experiences of continence service leads in England on key service and continence management characteristics in order to identify and to improve our understanding of barriers to a good-quality service and potential facilitators to develop and to improve services for older people with urinary incontinence (UI). Design Qualitative semistructured interviews using a purposive sample recruited across 16 continence services. Setting 3 acute and 13 primary care National Health Service Trusts in England. Participants 16 continence service leads in England actively treating and managing older people with UI. Results In terms of barriers to a good-quality service, participants highlighted a failure on the part of commissioners, managers and other health professionals in recognising the problem of UI and in acknowledging the importance of continence for older people and prevalent negative attitudes towards continence and older people. Patient assessment and continence promotion regardless of age, rather than pad provision, were identified as important steps for a good-quality service for older people with UI. More rapid and appropriate patient referral pathways, investment in service capacity, for example, more trained staff and strengthened interservice collaborations and a higher profile within medical and nurse training were specified as being important facilitators for delivering an equitable and high-quality continence service. There is a need, however, to consider the accounts given by our participants as perhaps serving the interests of their professional group within the context of interprofessional work. Conclusions Our data point to important barriers and facilitators of a good-quality service for older people with UI, from the perspective of continence service leads. Further research should address the views of other stakeholders, and explore options for the empirical evaluation of the effectiveness of identified service facilitators.Funding was received from the New Dynamics of Ageing Programme, led by the Economic & Social Research Council, UK (grantnumber RES-353-25-0010)

    Stryker Osteonics: Prosthetic Knee Joint

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    We examine, within a simple bearing model of a knee joint that only consideres pure sliding, the effect of the presence of a small vertical hole in the load area on the fluid film properties. The calculations indicate that fluid is entrapped in such a hole, which, for constant load, causes a smaller minimal film separation of the two surfaces. This will lower the horizontal friction, but may also bring about surface contact in high load situations

    Strangeness contribution to the vector and axial form factors of the nucleon

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    The strangeness contribution to the vector and axial form factors of the nucleon is presented for momentum transfers in the range 0.45<Q2<1.00.45<Q^2<1.0 GeV2^2. The results are obtained via a combined analysis of forward-scattering parity-violating elastic e⃗p\vec{e}p asymmetry data from the G0G^0 and HAPPEx experiments at Jefferson Lab, and elastic νp\nu p and νˉp\bar{\nu} p scattering data from Experiment 734 at Brookhaven National Laboratory. The parity-violating asymmetries measured in elastic e⃗p\vec{e}p scattering at forward angles establish a relationship between the strange vector form factors GEsG_E^s and GMsG_M^s, with little sensitivity to the strange axial form factor GAsG_A^s. On the other hand, elastic neutrino scattering at low Q2Q^2 is dominated by the axial form factor, with still some significant sensitivity to the vector form factors as well. The combination of the two data sets allows the simultaneous extraction of GEsG_E^s, GMsG_M^s, and GAsG_A^s over a significant range of Q2Q^2 for the very first time.Comment: 3 pages, 1 figure, will appear in AIP Conference Proceedings for PANIC 200

    Vibrational Stability of NLC Linac accelerating structure

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    The vibration of components of the NLC linac, such as accelerating structures and girders, is being studied both experimentally and analytically. Various effects are being considered including structural resonances and vibration caused by cooling water in the accelerating structure. This paper reports the status of ongoing work.Comment: 3 pages 8 figures Presented at EPAC 2002 Paris Franc

    The political economy of universal health coverage. Background paper for the global symposium on health systems research

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    This paper is one of several in a series commissioned by the World Health Organization for the First Global Symposium on Health Systems Research, held 16-19 November, 2010, in Montreux, Switzerland. The goal of these papers is to initiate a dialogue on the critical issues in health systems research. The opinions expressed in these papers are those of the authors and do not necessarily reflect those of the symposium organizers. This paper has financial support from the Rockefeller Foundation; the Alliance for Health Policy and Systems Research; and the German Federal Ministry for Economic Cooperation and Development (GTZ)

    Use of Reversible Contraceptive Methods Among U.S. Women with Physical or Sensory Disabilities

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138241/1/psrh12031.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138241/2/psrh12031_am.pd

    Ethical issues in qualitative research addressing sensitive issues with children and young people

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    How do adults understand youth? How do their conceptions inform interventions into young lives or involve young people&#39;s experiences? This volume tackles these questions by exploring adults&#39; ideas about youth
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