1,813 research outputs found

    The role of economics in the QUERI program: QUERI Series.

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    Background: The United States (U.S.) Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI) has implemented economic analyses in single-site and multi-site clinical trials. To date, no one has reviewed whether the QUERI Centers are taking an optimal approach to doing so. Consistent with the continuous learning culture of the QUERI Program, this paper provides such a reflection. Methods: We present a case study of QUERI as an example of how economic considerations can and should be integrated into implementation research within both single and multi-site studies. We review theoretical and applied cost research in implementation studies outside and within VA. We also present a critique of the use of economic research within the QUERI program. Results: Economic evaluation is a key element of implementation research. QUERI has contributed many developments in the field of implementation but has only recently begun multisite implementation trials across multiple regions within the national VA healthcare system. These trials are unusual in their emphasis on developing detailed costs of implementation, as well as in the use of business case analyses (budget impact analyses). Conclusion: Economics appears to play an important role in QUERI implementation studies, only after implementation has reached the stage of multi-site trials. Economic analysis could better inform the choice of which clinical best practices to implement and the choice of implementation interventions to employ. QUERI economics also would benefit from research on costing methods and development of widely accepted international standards for implementation economics.implementation science; cost analysis; cost-effectiveness; health care cost; health systems;

    The role of economics in the QUERI program: QUERI Series

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    <p>Abstract</p> <p>Background</p> <p>The United States (U.S.) Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI) has implemented economic analyses in single-site and multi-site clinical trials. To date, no one has reviewed whether the QUERI Centers are taking an optimal approach to doing so. Consistent with the continuous learning culture of the QUERI Program, this paper provides such a reflection.</p> <p>Methods</p> <p>We present a case study of QUERI as an example of how economic considerations can and should be integrated into implementation research within both single and multi-site studies. We review theoretical and applied cost research in implementation studies outside and within VA. We also present a critique of the use of economic research within the QUERI program.</p> <p>Results</p> <p>Economic evaluation is a key element of implementation research. QUERI has contributed many developments in the field of implementation but has only recently begun multi-site implementation trials across multiple regions within the national VA healthcare system. These trials are unusual in their emphasis on developing detailed costs of implementation, as well as in the use of business case analyses (budget impact analyses).</p> <p>Conclusion</p> <p>Economics appears to play an important role in QUERI implementation studies, only after implementation has reached the stage of multi-site trials. Economic analysis could better inform the choice of which clinical best practices to implement and the choice of implementation interventions to employ. QUERI economics also would benefit from research on costing methods and development of widely accepted international standards for implementation economics.</p

    Roza Irrigation District

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    Presented at the 2002 USCID/EWRI conference, Energy, climate, environment and water - issues and opportunities for irrigation and drainage on July 9-12 in San Luis Obispo, California.The Roza Irrigation District (Roza), in the Yakima Valley of Washington State, received only 37 percent of its water right entitlement in the 1994 and 2001 irrigation seasons due to its junior water status in the basin. A reduction in water allocation of this magnitude places a great deal of stress on farmers and their crops, and hinders the District's ability to deliver water. Faced with having to operate with less than 50 percent (600 cfs) of design flow, Roza has become one of the most progressive irrigation districts in the Pacific Northwest with respect to water conservation by applying new and innovative technology. Since 1991, Roza has developed numerous partnerships to help fund and apply resourceful technology to water conservation measures. Initially, Armtec and UMA introduced the automated single-leaf over shot gate, which was applied to numerous main canal checks to provide constant level control for pipeline turnouts and pumping plants. One of Roza's most successful partnerships has been with the United States Bureau of Reclamation (Bureau) Water Conservation Field Services Program in Yakima, and Aqua Systems 2000 Inc. (AS2I) from Lethbridge, Alberta, Canada. The partnership began in 1997 when an existing flashboard check structure was replaced with an automated Langemann gate. The success of this project, cost shared with the Bureau, prompted Roza to discontinue building new multi-bay single-leaf over shot structures and building or retrofitting eight structures with a single Langemann gate, the largest being 24-feet wide. The partnership with the Bureau and AS2I expanded to include Supervisory Control and Data Acquisition (SCADA) on two existing main canal checks and a re-regulation reservoir. These innovative projects include flow control using undershot gates, spill flow monitoring using ultrasonic level technology, downstream canal level control using a variable speed pump and modulating valve, and remote communications via spread spectrum radio, dedicated phone line, and cellular digital modem technology. The SCADA system was recently expanded with the incorporation of an Acoustic Doppler Flow Meter (ADFM) downstream of the diversion point. In addition, Roza also partnered with MagnaDrive, Inc. (MagnaDrive) and AS2I to demonstrate variable speed pump control on an existing pumping plant. MagnaDrive supplied a magnetic coupler rather than a variable frequency drive (VFD), and AS2I provided the controls design and software to the flow control project. The success of these projects has enabled Roza to reduce low-end operational flows from 600 cfs to 280 cfs in water short years and still provide reliable service to its water users

    Security of high-dimensional quantum key distribution protocols using Franson interferometers

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    Franson interferometers are increasingly being proposed as a means of securing high-dimensional energy-time entanglement-based quantum key distribution (QKD) systems. Heuristic arguments have been proposed that purport to demonstrate the security of these schemes. We show, however, that such systems are vulnerable to attacks that localize the photons to several temporally separate locations. This demonstrates that a single pair of Franson interferometers is not a practical approach to securing high-dimensional energy-time entanglement based QKD. This observations leads us to investigate the security of modified Franson-based-protocols, where Alice and Bob have two or more Franson interferometers. We show that such setups can improve the sensitivity against attacks that localize the photons to multiple temporal locations. While our results do not constituting a full security proof, they do show that a single pair of Franson interferometers is not secure and that multiple such interferometers could be a promising candidate for experimentally realizable high-dimensional QKD.Comment: 14 pages (single column format

    Is requiring Research Integrity Advisors a useful policy for improving research integrity? :A census of advisors in Australia

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    Research Integrity Advisors are used in Australia to provide impartial guidance to researchers who have questions about any aspect of responsible research practice. Every Australian institution conducting research must provide access to trained advisors. This national policy could be an important part of creating a safe environment for discussing research integrity issues and thus resolving issues. We conducted the first formal study of advisors, using a census of every Australian advisor to discover their workload and attitudes to their role. We estimated there are 739 advisors nationally. We received responses to our questions from 192. Most advisors had a very light workload, with an median of just 0.5 days per month. Thirteen percent of advisors had not received any training, and some advisors only discovered they were an advisor after our approach. Most advisors were positive about their ability to help colleagues deal with integrity issues. The main desired changes were for greater advertising of their role and a desire to promote good practice rather than just supporting potential issues. Advisors might be a useful policy for supporting research integrity, but some advisors need better institutional support in terms of training and raising awareness.</p

    Identifying patterns of item missing survey data using latent groups: An observational study

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    Objectives: To examine whether respondents to a survey of health and physical activity and potential determinants could be grouped according to the questions they missed, known as ‘item missing’. Design: Observational study of longitudinal data. Setting: Residents of Brisbane, Australia. Participants: 6901 people aged 40–65 years in 2007. Materials and methods: We used a latent class model with a mixture of multinomial distributions and chose the number of classes using the Bayesian information criterion. We used logistic regression to examine if participants’ characteristics were associated with their modal latent class. We used logistic regression to examine whether the amount of item missing in a survey predicted wave missing in the following survey. Results: Four per cent of participants missed almost one-fifth of the questions, and this group missed more questions in the middle of the survey. Eighty-three per cent of participants completed almost every question, but had a relatively high missing probability for a question on sleep time, a question which had an inconsistent presentation compared with the rest of the survey. Participants who completed almost every question were generally younger and more educated. Participants who completed more questions were less likely to miss the next longitudinal wave. Conclusions: Examining patterns in item missing data has improved our understanding of how missing data were generated and has informed future survey design to help reduce missing data

    Measuring the elements of the optical density matrix

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    Most methods for experimentally reconstructing the quantum state of light involve determining a quasiprobability distribution such as the Wigner function. In this paper we present a scheme for measuring individual density matrix elements in the photon number state representation. Remarkably, the scheme is simple, involving two beam splitters and a reference field in a coherent state.Comment: 6 pages and 1 figur

    Effect of metoprolol on myocardial function and energetics in patients with nonischemic dilated cardiomyopathy: A randomized, double-blind, placebo-controlled study

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    AbstractObjectives. This study examined the of metoprolol on left ventricular performance, efficiency, neurohormonal activation and myocardial respiratory quotient in patients with dilated cardiomyopathy.Background.The mechanism by which beta-adrenergie blockade improves ejection fraction in patients with dilated cardiomyopathy remains an enigma. Thus, we undertook an extensive hemodynamic evaluation of this mechanism. In addition, because animal models have shown that catecholamine exposure may increase relative fatty acid utilization, we hypothesized that antagonism of sympathetic stimulation may result in increased carbohydrate utilization.Methods. This was a randomized, double-blind, prospective trial in which 24 men with nonischemic dilated cardiomyopathy underwent cardiac catheterization before and after 3 months of therapy with metoprolol (n = 15) or placebo (n = 9) in addition to standard therapy. Pressure-volume relations were examined using a micromanometer catheter and digital ventriculography.Results. At baseline, the placebo-treated patients had somewhat more advanced left ventricular dysfunction. Ejection fraction and left ventricular performance improved only in the metoprolol-treated patients. Stroke and minute work increased without an increase in myocardial oxgen consumption, suggesting increased myocardial efficiency. Further increases in ejection fraction were seen between 3 and 6 months in the metoprolol group. The placebo group had a significant increase in ejection fraction only after crossover to metoprolol. A significant relation the change in coronary sinus norepinephrine and myocardial respiratory quotient was seen, suggesting a possible effect of adrenergic deactivation on substrate utilization.Conclusions. These data demonstrate that in patients with cardiomyopthy, metoprolol treatment improves myocardial performance and energetics, and favorably alters substrate utilization. Beta-adrenergic blocking agents, such as metoprolol, are hemodynamically and energetically beneficial in the treatment of myocardial failure

    Two-photon exclusive decays Bs→η(ηâ€Č)γγB_s \to \eta (\eta') \gamma\gamma and B→KγγB \to K \gamma\gamma

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    The exclusive decay modes B→KγγB \to K \gamma\gamma and Bs→η(ηâ€Č)γγB_s \to \eta (\eta') \gamma\gamma are shown to have significant branching ratios of approximately 0.5×10−70.5\times 10^{-7}. This first calculation of these modes employs a model based on a cascade transition B→Vγ→PγγB\to V\gamma\to P\gamma\gamma for estimating the long-distance contribution and the process b→sγγb\to s\gamma\gamma for the short distance one.Comment: 11 Page
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