The Experts below are selected from a list of 2982 Experts worldwide ranked by ideXlab platform
Sandra L. Hofferth - One of the best experts on this subject based on the ideXlab platform.
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A gestational Vulnerability Window for smoking exposure and the increased risk of preterm birth: how timing and intensity of maternal smoking matter
Reproductive health, 2019Co-Authors: Anthony J. Kondracki, Sandra L. HofferthAbstract:Reducing the incidence of preterm birth is a national priority. Maternal cigarette smoking is strongly and consistently associated with preterm birth. The objective of this study was to examine prenatal exposure based on combined measures of timing (by trimester) and intensity level (the number of cigarettes smoked per day) of maternal smoking to identify a pregnancy period with the highest risk of preterm birth. A sample of 2,485,743 singleton births was drawn from the 2010 National Center of Health Statistics (NCHS) linked birth/infant death file of US residents in 33 states that implemented the revised 2003 birth certificate. Nine mutually exclusive smoking status categories were created to assess prenatal exposure across pregnancy in association with preterm birth. Gestational age was based on the obstetric estimate. Multiple logistic regression analyses were conducted to compare the odds of preterm birth among women who smoked at different intensity levels in the second or third trimester with those who smoked only in the first trimester. Overall, 7.95% of women had a preterm birth; 8.90% of low intensity (less than a pack/day) smokers in the first trimester only, 12.99% of low and 15.38% of high intensity (pack a day or more) smokers in the first two trimesters, and 10.56% of low and 11.35% of high intensity smokers in all three trimesters delivered preterm. First and second trimester high (aOR 1.85, 95% CI: 1.66, 2.06) and low intensity smokers (aOR 1.51, 95% CI: 1.41, 1.61) had higher odds of preterm birth compared to those who smoked less than a pack a day only in the first trimester, but the odds did not increase for all three trimester smokers relative to the first and second trimester smokers. In sensitivity analysis, adjustment for exposure misclassification error corrected data and testing for effect modification by maternal race/ethnicity found no significant interaction. This study documented a biologically plausible Vulnerability Window for smoking exposure and the increased risk of preterm birth. For women who do not modify their smoking behavior preconception, preterm birth risk of smoking remains low until late in the first trimester.
Hofferth Sandra - One of the best experts on this subject based on the ideXlab platform.
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A gestational Vulnerability Window for smoking exposure and the increased risk of preterm birth: how timing and intensity of maternal smoking matter
'Wiley', 2019Co-Authors: Kondracki Anthony, Hofferth SandraAbstract:Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Background: Reducing the incidence of preterm birth is a national priority. Maternal cigarette smoking is strongly and consistently associated with preterm birth. The objective of this study was to examine prenatal exposure based on combined measures of timing (by trimester) and intensity level (the number of cigarettes smoked per day) of maternal smoking to identify a pregnancy period with the highest risk of preterm birth. Methods: A sample of 2,485,743 singleton births was drawn from the 2010 National Center of Health Statistics (NCHS) linked birth/infant death file of US residents in 33 states that implemented the revised 2003 birth certificate. Nine mutually exclusive smoking status categories were created to assess prenatal exposure across pregnancy in association with preterm birth. Gestational age was based on the obstetric estimate. Multiple logistic regression analyses were conducted to compare the odds of preterm birth among women who smoked at different intensity levels in the second or third trimester with those who smoked only in the first trimester. Results: Overall, 7.95% of women had a preterm birth; 8.90% of low intensity (less than a pack/day) smokers in the first trimester only, 12.99% of low and 15.38% of high intensity (pack a day or more) smokers in the first two trimesters, and 10.56% of low and 11.35% of high intensity smokers in all three trimesters delivered preterm. First and second trimester high (aOR 1.85, 95% CI: 1.66, 2.06) and low intensity smokers (aOR 1.51, 95% CI: 1.41, 1.61) had higher odds of preterm birth compared to those who smoked less than a pack a day only in the first trimester, but the odds did not increase for all three trimester smokers relative to the first and second trimester smokers. In sensitivity analysis, adjustment for exposure misclassification error corrected data and testing for effect modification by maternal race/ ethnicity found no significant interaction. Conclusions: This study documented a biologically plausible Vulnerability Window for smoking exposure and the increased risk of preterm birth. For women who do not modify their smoking behavior preconception, preterm birth risk of smoking remains low until late in the first trimester.Support for this research was provided by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (Grant R01-HD053654, S. Hofferth, PI, and R24-HD041041 to the Maryland Population Research Center). Partial funding for open access provided by the UMD Libraries' Open Access Publishing Fund
Peter Van Roy - One of the best experts on this subject based on the ideXlab platform.
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reducing the Vulnerability Window in distributed transactional protocols
European Conference on Computer Systems, 2015Co-Authors: Manuel Bravo, Paolo Romano, Luis Rodrigues, Peter Van RoyAbstract:In this paper, we introduce a technique that can be used by distributed transactional protocols to reduce the Vulnerability Window of transactions. For this purpose, we propose a so far unexplored (to the best of our knowledge) usage of hybrid clocks. On one hand, loosely synchronized physical clocks are used to maximize the freshness of the snapshots used by transactions to read. On the other hand, logical clocks are used to reduce the extent to which the snapshot of update transactions is advanced upon their commit.We claim that the joint usage of these two techniques can potentially reduce the abort rate in comparison to previous protocols such as Clock-SI, GMU, and SCORe.
Amir Roth - One of the best experts on this subject based on the ideXlab platform.
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store Vulnerability Window svw re execution filtering for enhanced load optimization
International Symposium on Computer Architecture, 2005Co-Authors: Amir RothAbstract:The load-store unit is a performance critical component of a dynamically-scheduled processor. It is also a complex and non-scalable component. Several recently proposed techniques use some form of speculation to simplify the load-store unit and check this speculation by re-executing some of the loads prior to commit. We call such techniques load optimizations. One recent load optimization improves load queue (LQ) scalability by using re-execution rather than associative search to check speculative intra- and inter- thread memory ordering. A second technique improves store queue (SQ) scalability by speculatively filtering some load accesses and some store entries from it and re-executing loads to check that speculation. A third technique speculatively removes redundant loads from the execution engine; re-execution detects false eliminations. Unfortunately, the benefits of a load optimization are often mitigated by re-execution itself. Re-execution contends for cache bandwidth with store commit, and serializes load re-execution with subsequent store commit. If a given load optimization requires a sufficient number of load re-executions, the aggregate re-execution cost may overwhelm the benefits of the technique entirely and even cause drastic slowdowns. Store Vulnerability Window (SVW) is a new mechanism that significantly reduces the re-execution requirements of a given load optimization. SVW is based on monotonic store sequence numbering and an adaptation of Bloom filtering. The cost of a typical SVW implementation is a 1KB buffer and a 16-bit field per LQ entry. Across the three optimizations we study, SVW reduces re-executions by an average of 85%. This reduction relieves cache port contention and removes many of the dynamic serialization events that contribute the bulk of re-executionýs cost, allows these load optimizations to perform up to their full potential. For the speculative SQ, this means the chance to perform at all, as without SVW it posts significant slowdowns.
Anthony J. Kondracki - One of the best experts on this subject based on the ideXlab platform.
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A gestational Vulnerability Window for smoking exposure and the increased risk of preterm birth: how timing and intensity of maternal smoking matter
Reproductive health, 2019Co-Authors: Anthony J. Kondracki, Sandra L. HofferthAbstract:Reducing the incidence of preterm birth is a national priority. Maternal cigarette smoking is strongly and consistently associated with preterm birth. The objective of this study was to examine prenatal exposure based on combined measures of timing (by trimester) and intensity level (the number of cigarettes smoked per day) of maternal smoking to identify a pregnancy period with the highest risk of preterm birth. A sample of 2,485,743 singleton births was drawn from the 2010 National Center of Health Statistics (NCHS) linked birth/infant death file of US residents in 33 states that implemented the revised 2003 birth certificate. Nine mutually exclusive smoking status categories were created to assess prenatal exposure across pregnancy in association with preterm birth. Gestational age was based on the obstetric estimate. Multiple logistic regression analyses were conducted to compare the odds of preterm birth among women who smoked at different intensity levels in the second or third trimester with those who smoked only in the first trimester. Overall, 7.95% of women had a preterm birth; 8.90% of low intensity (less than a pack/day) smokers in the first trimester only, 12.99% of low and 15.38% of high intensity (pack a day or more) smokers in the first two trimesters, and 10.56% of low and 11.35% of high intensity smokers in all three trimesters delivered preterm. First and second trimester high (aOR 1.85, 95% CI: 1.66, 2.06) and low intensity smokers (aOR 1.51, 95% CI: 1.41, 1.61) had higher odds of preterm birth compared to those who smoked less than a pack a day only in the first trimester, but the odds did not increase for all three trimester smokers relative to the first and second trimester smokers. In sensitivity analysis, adjustment for exposure misclassification error corrected data and testing for effect modification by maternal race/ethnicity found no significant interaction. This study documented a biologically plausible Vulnerability Window for smoking exposure and the increased risk of preterm birth. For women who do not modify their smoking behavior preconception, preterm birth risk of smoking remains low until late in the first trimester.
