The Experts below are selected from a list of 8754 Experts worldwide ranked by ideXlab platform
Gary E Swan - One of the best experts on this subject based on the ideXlab platform.
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Measures of abstinence in clinical trials: issues and recommendations.
Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco, 2003Co-Authors: John R. Hughes, Josue P Keely, Robyn Richmond, Raymond Niaura, Deborah J. Ossip-klein, Gary E SwanAbstract:A workgroup formed by the Society for Research on Nicotine and Tobacco reviewed the literature on abstinence measures used in trials of smoking cessation interventions. We recommend that trials report multiple measures of abstinence. However, at a minimum we recommend that trial: (a) report prolonged abstinence (i.e., sustained abstinence after an initial Period in which smoking is not counted as a failure) as the preferred measure, plus point prevalence as a secondary measure; (b) use 7 consecutive days of smoking or smoking on > or = 1 day of 2 consecutive weeks to define treatment failure; (c) include non-cigarette tobacco use, but not nicotine medications in definitions of failure; and (d) report results from survival analysis to describe outcomes more fully. Trials of smokers willing to set a quit date should tie all follow-ups to the quit date and report 6- and/or 12-month abstinence rates. For these trials, we recommend an initial 2-week Grace Period for prolonged abstinence definitions; however, the Period may vary, depending on the presumed mechanism of the treatment. Trials of smokers who may not be currently trying to quit should tie follow-up to the initiation of the intervention and should report a prolonged abstinence measure of > or = 6-month duration and point prevalence rates at 6- and 12-month follow-ups. The Grace Period for these trials will depend on the time necessary for treatment dissemination, which will vary depending on the treatment, setting, and population. Trials that use short-term follow-ups ( or = 4 weeks. We again recommend a 2-week Grace Period; however, that Period can vary.
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measures of abstinence in clinical trials issues and recommendations
Nicotine & Tobacco Research, 2003Co-Authors: John R. Hughes, Josue P Keely, Deborah J Ossipklein, Robyn Richmond, Raymond Niaura, Gary E SwanAbstract:A workgroup formed by the Society for Research on Nicotine and Tobacco reviewed the literature on abstinence measures used in trials of smoking cessation interventions. We recommend that trials report multiple measures of abstinence. However, at a minimum we recommend that trial: (a) report prolonged abstinence (i.e., sustained abstinence after an initial Period in which smoking is not counted as a failure) as the preferred measure, plus point prevalence as a secondary measure; (b) use 7 consecutive days of smoking or smoking on ≥1 day of 2 consecutive weeks to define treatment failure; (c) include non-cigarette tobacco use, but not nicotine medications in definitions of failure; and (d) report results from survival analysis to describe outcomes more fully. Trials of smokers willing to set a quit date should tie all follow-ups to the quit date and report 6- and/or 12-month abstinence rates. For these trials, we recommend an initial 2-week Grace Period for prolonged abstinence definitions; however, the Period may vary, depending on the presumed mechanism of the treatment. Trials of smokers who may not be currently trying to quit should tie follow-up to the initiation of the intervention and should report a prolonged abstinence measure of ≥6-month duration and point prevalence rates at 6- and 12-month follow-ups. The Grace Period for these trials will depend on the time necessary for treatment dissemination, which will vary depending on the treatment, setting, and population. Trials that use short-term follow-ups (≤3 months) to demonstrate possible efficacy should report a prolonged abstinence measure of ≥4 weeks. We again recommend a 2-week Grace Period; however, that Period can vary.
K Gopinath - One of the best experts on this subject based on the ideXlab platform.
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a frugal approach to reduce rcu Grace Period overhead
European Conference on Computer Systems, 2018Co-Authors: Aravinda Prasad, K GopinathAbstract:Grace Period computation is a core part of the Read-Copy-Update (RCU) synchronization technique that determines the safe time to reclaim the deferred objects' memory. We first show that the eager Grace Period computation employed in the Linux kernel is appropriate only for enterprise workloads such as web and database servers where a large amount of reclaimable memory awaits the completion of a Grace Period. However, such memory is negligible in High-Performance Computing (HPC) and mostly idling environments due to limited OS kernel activity. Hence an eager approach is not only futile but also detrimental as the CPU cycles consumed to compute a Grace Period leads to jitter in HPC and frequent CPU wake-ups in idle environments. We design frugal Grace Periods, an economical Grace Period computation for non-enterprise environments that consume fewer CPU cycles. In addition, we reduce the number of Grace Periods either by using heuristics or by letting the memory allocator to explicitly request for a Grace Period only when it is running out of free objects. Our implementation in the Linux kernel reduces the number of Grace Periods by 68% to 99%, reduces the CPU time consumed by Grace Periods by 39% to 99%, improves the throughput by up to 28% for NAS parallel benchmarks and increases the CPU time spent in low power states by 2.4x when the system is idle.
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EuroSys - A frugal approach to reduce RCU Grace Period overhead
Proceedings of the Thirteenth EuroSys Conference, 2018Co-Authors: Aravinda Prasad, K GopinathAbstract:Grace Period computation is a core part of the Read-Copy-Update (RCU) synchronization technique that determines the safe time to reclaim the deferred objects' memory. We first show that the eager Grace Period computation employed in the Linux kernel is appropriate only for enterprise workloads such as web and database servers where a large amount of reclaimable memory awaits the completion of a Grace Period. However, such memory is negligible in High-Performance Computing (HPC) and mostly idling environments due to limited OS kernel activity. Hence an eager approach is not only futile but also detrimental as the CPU cycles consumed to compute a Grace Period leads to jitter in HPC and frequent CPU wake-ups in idle environments. We design frugal Grace Periods, an economical Grace Period computation for non-enterprise environments that consume fewer CPU cycles. In addition, we reduce the number of Grace Periods either by using heuristics or by letting the memory allocator to explicitly request for a Grace Period only when it is running out of free objects. Our implementation in the Linux kernel reduces the number of Grace Periods by 68% to 99%, reduces the CPU time consumed by Grace Periods by 39% to 99%, improves the throughput by up to 28% for NAS parallel benchmarks and increases the CPU time spent in low power states by 2.4x when the system is idle.
John R. Hughes - One of the best experts on this subject based on the ideXlab platform.
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Measures of abstinence in clinical trials: issues and recommendations.
Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco, 2003Co-Authors: John R. Hughes, Josue P Keely, Robyn Richmond, Raymond Niaura, Deborah J. Ossip-klein, Gary E SwanAbstract:A workgroup formed by the Society for Research on Nicotine and Tobacco reviewed the literature on abstinence measures used in trials of smoking cessation interventions. We recommend that trials report multiple measures of abstinence. However, at a minimum we recommend that trial: (a) report prolonged abstinence (i.e., sustained abstinence after an initial Period in which smoking is not counted as a failure) as the preferred measure, plus point prevalence as a secondary measure; (b) use 7 consecutive days of smoking or smoking on > or = 1 day of 2 consecutive weeks to define treatment failure; (c) include non-cigarette tobacco use, but not nicotine medications in definitions of failure; and (d) report results from survival analysis to describe outcomes more fully. Trials of smokers willing to set a quit date should tie all follow-ups to the quit date and report 6- and/or 12-month abstinence rates. For these trials, we recommend an initial 2-week Grace Period for prolonged abstinence definitions; however, the Period may vary, depending on the presumed mechanism of the treatment. Trials of smokers who may not be currently trying to quit should tie follow-up to the initiation of the intervention and should report a prolonged abstinence measure of > or = 6-month duration and point prevalence rates at 6- and 12-month follow-ups. The Grace Period for these trials will depend on the time necessary for treatment dissemination, which will vary depending on the treatment, setting, and population. Trials that use short-term follow-ups ( or = 4 weeks. We again recommend a 2-week Grace Period; however, that Period can vary.
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measures of abstinence in clinical trials issues and recommendations
Nicotine & Tobacco Research, 2003Co-Authors: John R. Hughes, Josue P Keely, Deborah J Ossipklein, Robyn Richmond, Raymond Niaura, Gary E SwanAbstract:A workgroup formed by the Society for Research on Nicotine and Tobacco reviewed the literature on abstinence measures used in trials of smoking cessation interventions. We recommend that trials report multiple measures of abstinence. However, at a minimum we recommend that trial: (a) report prolonged abstinence (i.e., sustained abstinence after an initial Period in which smoking is not counted as a failure) as the preferred measure, plus point prevalence as a secondary measure; (b) use 7 consecutive days of smoking or smoking on ≥1 day of 2 consecutive weeks to define treatment failure; (c) include non-cigarette tobacco use, but not nicotine medications in definitions of failure; and (d) report results from survival analysis to describe outcomes more fully. Trials of smokers willing to set a quit date should tie all follow-ups to the quit date and report 6- and/or 12-month abstinence rates. For these trials, we recommend an initial 2-week Grace Period for prolonged abstinence definitions; however, the Period may vary, depending on the presumed mechanism of the treatment. Trials of smokers who may not be currently trying to quit should tie follow-up to the initiation of the intervention and should report a prolonged abstinence measure of ≥6-month duration and point prevalence rates at 6- and 12-month follow-ups. The Grace Period for these trials will depend on the time necessary for treatment dissemination, which will vary depending on the treatment, setting, and population. Trials that use short-term follow-ups (≤3 months) to demonstrate possible efficacy should report a prolonged abstinence measure of ≥4 weeks. We again recommend a 2-week Grace Period; however, that Period can vary.
Aravinda Prasad - One of the best experts on this subject based on the ideXlab platform.
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a frugal approach to reduce rcu Grace Period overhead
European Conference on Computer Systems, 2018Co-Authors: Aravinda Prasad, K GopinathAbstract:Grace Period computation is a core part of the Read-Copy-Update (RCU) synchronization technique that determines the safe time to reclaim the deferred objects' memory. We first show that the eager Grace Period computation employed in the Linux kernel is appropriate only for enterprise workloads such as web and database servers where a large amount of reclaimable memory awaits the completion of a Grace Period. However, such memory is negligible in High-Performance Computing (HPC) and mostly idling environments due to limited OS kernel activity. Hence an eager approach is not only futile but also detrimental as the CPU cycles consumed to compute a Grace Period leads to jitter in HPC and frequent CPU wake-ups in idle environments. We design frugal Grace Periods, an economical Grace Period computation for non-enterprise environments that consume fewer CPU cycles. In addition, we reduce the number of Grace Periods either by using heuristics or by letting the memory allocator to explicitly request for a Grace Period only when it is running out of free objects. Our implementation in the Linux kernel reduces the number of Grace Periods by 68% to 99%, reduces the CPU time consumed by Grace Periods by 39% to 99%, improves the throughput by up to 28% for NAS parallel benchmarks and increases the CPU time spent in low power states by 2.4x when the system is idle.
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EuroSys - A frugal approach to reduce RCU Grace Period overhead
Proceedings of the Thirteenth EuroSys Conference, 2018Co-Authors: Aravinda Prasad, K GopinathAbstract:Grace Period computation is a core part of the Read-Copy-Update (RCU) synchronization technique that determines the safe time to reclaim the deferred objects' memory. We first show that the eager Grace Period computation employed in the Linux kernel is appropriate only for enterprise workloads such as web and database servers where a large amount of reclaimable memory awaits the completion of a Grace Period. However, such memory is negligible in High-Performance Computing (HPC) and mostly idling environments due to limited OS kernel activity. Hence an eager approach is not only futile but also detrimental as the CPU cycles consumed to compute a Grace Period leads to jitter in HPC and frequent CPU wake-ups in idle environments. We design frugal Grace Periods, an economical Grace Period computation for non-enterprise environments that consume fewer CPU cycles. In addition, we reduce the number of Grace Periods either by using heuristics or by letting the memory allocator to explicitly request for a Grace Period only when it is running out of free objects. Our implementation in the Linux kernel reduces the number of Grace Periods by 68% to 99%, reduces the CPU time consumed by Grace Periods by 39% to 99%, improves the throughput by up to 28% for NAS parallel benchmarks and increases the CPU time spent in low power states by 2.4x when the system is idle.
Charles S Morrison - One of the best experts on this subject based on the ideXlab platform.
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injectable contraception what should the longest interval be for reinjections
Contraception, 2008Co-Authors: Markus J. Steiner, Cynthia Kwok, Josaphat Byamugisha, Thulani Magwali, Somchai Sriplienchan, Tsungai Chipato, Francis Mmiro, John Stanback, Sungwal Rugpao, Charles S MorrisonAbstract:Abstract Background Progestin-only injectable contraceptives continue to gain in popularity, but uncertainty remains about pregnancy risk among women late for reinjection. The World Health Organization (WHO) recommends a “Grace Period” of 2 weeks after the scheduled 13-week reinjection. Beyond 2 weeks, however, many providers send late clients home to await menses. Study design A prospective cohort study in Uganda, Zimbabwe and Thailand followed users of depot-medroxyprogesterone acetate (DMPA) for up to 24 months. Users were tested for pregnancy at every reinjection, allowing analysis of pregnancy risk among late comers. Results The analysis consists of 2290 participants contributing 13,608 DMPA intervals. The pregnancy risks per 100 women-years for “on time” [0.6; 95% confidence interval (CI), 0.33–0.92], “2-week Grace” (0.0; 95% CI, 0.0–1.88) and “4-week Grace” (0.4; 95% CI, 0.01–2.29) injections were low and virtually identical. Conclusion Extending the current WHO Grace Period for DMPA reinjection from 2 to 4 weeks does not increase pregnancy risk and could increase contraceptive continuation.
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injectable contraception what should the longest interval be for reinjections
Contraception, 2008Co-Authors: Markus J. Steiner, Cynthia Kwok, Josaphat Byamugisha, Thulani Magwali, Somchai Sriplienchan, Tsungai Chipato, Francis Mmiro, John Stanback, Sungwal Rugpao, Charles S MorrisonAbstract:Abstract Background Progestin-only injectable contraceptives continue to gain in popularity, but uncertainty remains about pregnancy risk among women late for reinjection. The World Health Organization (WHO) recommends a “Grace Period” of 2 weeks after the scheduled 13-week reinjection. Beyond 2 weeks, however, many providers send late clients home to await menses. Study design A prospective cohort study in Uganda, Zimbabwe and Thailand followed users of depot-medroxyprogesterone acetate (DMPA) for up to 24 months. Users were tested for pregnancy at every reinjection, allowing analysis of pregnancy risk among late comers. Results The analysis consists of 2290 participants contributing 13,608 DMPA intervals. The pregnancy risks per 100 women-years for “on time” [0.6; 95% confidence interval (CI), 0.33–0.92], “2-week Grace” (0.0; 95% CI, 0.0–1.88) and “4-week Grace” (0.4; 95% CI, 0.01–2.29) injections were low and virtually identical. Conclusion Extending the current WHO Grace Period for DMPA reinjection from 2 to 4 weeks does not increase pregnancy risk and could increase contraceptive continuation.
