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Ballard

The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Manju Monga – 1st expert on this subject based on the ideXlab platform

  • prior knowledge of obstetric gestational age and possible bias of Ballard score
    Obstetrics & Gynecology, 1999
    Co-Authors: Laurette N Smith, Vivek H Dayal, Manju Monga

    Abstract:

    Abstract Objective: To determine whether prior knowledge of obstetric estimate of gestational age creates a bias in assignment of gestational age by the Ballard assessment score. Methods: The Ballard assessment score was done on 82 infants weighing less than 2500 g by two examiners, one who had prior knowledge of best obstetric gestational age estimate and the other who was masked to that information. Obstetric gestational age was correlated with masked and unmasked score. Statistical analysis used Spearman rank correlation test, plotting the measurement means against the measurement differences, χ2, Wilcoxon signed-rank test, analysis of variance, and Student t test. Significance was assumed at P Results: There was high reliability (r = 0.84–0.86) between obstetric gestational age estimates (33.3 ± 3.0 weeks) and the gestational age derived from masked (34.3 ± 3.0 weeks) and unmasked (34.0 ± 3.0 weeks) Ballard scores. The mean difference between unmasked scores and gestational age was 1.38 ± 1.15 weeks and that between masked scores and obstetric gestational age was 1.40 ± 1.15 weeks, a nonsignificant difference. There was no significant difference in the number of cases with 100% agreement between masked and unmasked scores and obstetric gestational age or in the number of cases in which the score (masked or unmasked) differed by more than 2 weeks from obstetric gestational age. This study had over 99% power to detect a 1-week difference between the accuracy of masked and unmasked scores. Conclusion: Prior knowledge of obstetric gestational age did not bias the Ballard assessment score.

  • Prior knowledge of obstetric gestational age and possible bias of Ballard score.
    Obstetrics and gynecology, 1999
    Co-Authors: Laurette N Smith, Vivek H Dayal, Manju Monga

    Abstract:

    To determine whether prior knowledge of obstetric estimate of gestational age creates a bias in assignment of gestational age by the Ballard assessment score.
    The Ballard assessment score was done on 82 infants weighing less than 2500 g by two examiners, one who had prior knowledge of best obstetric gestational age estimate and the other who was masked to that information. Obstetric gestational age was correlated with masked and unmasked score. Statistical analysis used Spearman rank correlation test, plotting the measurement means against the measurement differences, chi2, Wilcoxon signed-rank test, analysis of variance, and Student t test. Significance was assumed at P < .05.
    There was high reliability (r = 0.84-0.86) between obstetric gestational age estimates (33.3 +/- 3.0 weeks) and the gestational age derived from masked (34.3 +/- 3.0 weeks) and unmasked (34.0 +/- 3.0 weeks) Ballard scores. The mean difference between unmasked scores and gestational age was 1.38 +/- 1.15 weeks and that between masked scores and obstetric gestational age was 1.40 +/- 1.15 weeks, a nonsignificant difference. There was no significant difference in the number of cases with 100% agreement between masked and unmasked scores and obstetric gestational age or in the number of cases in which the score (masked or unmasked) differed by more than 2 weeks from obstetric gestational age. This study had over 99% power to detect a 1-week difference between the accuracy of masked and unmasked scores.
    Prior knowledge of obstetric gestational age did not bias the Ballard assessment score.

Mohammad Narimani – 2nd expert on this subject based on the ideXlab platform

  • dynamic model of oxygen starved proton exchange membrane fuel cell using hybrid analytical numerical method
    Journal of Power Sources, 2015
    Co-Authors: Krishna Vijayaraghavan, J Devaal, Mohammad Narimani

    Abstract:

    Abstract One of the primary life-limiting factors in PEM fuel-cells arises from performance degradation resulting from transfer (crossover) leaks. Transfer leaks result in oxygen starvation and models of fuel cells under oxygen starved conditions would allow for detection of fault inception. This paper develops a unified fuel-cell model for when the fuel-cells can either deliver power (termed driving-mode, and for when the cell absorb power (termed driven-mode) for higher leak rates. The model captures the gradient of the reactants both in the GDL and in the flow channel in addition to capturing the various electro-chemical effects. The response of the model under normal conditions is first validated for normal operation against previously published experiments. The response of the model under oxygen-starved conditions is then validated against simulated leaks in three different cell architectures: a Ballard 9-cell Mk1100 stack where hydrogen is injected into one cell, and a Ballard 10-cell Mk902 stack and 20-cell Mk903 stack where hydrogen is injected into the upstream cathode flow. Finally, the response of the model is also validated against an actual leaky Mk902 cell. The model generally agrees well with the measured cell voltage data for all the above experiments.

Laurette N Smith – 3rd expert on this subject based on the ideXlab platform

  • prior knowledge of obstetric gestational age and possible bias of Ballard score
    Obstetrics & Gynecology, 1999
    Co-Authors: Laurette N Smith, Vivek H Dayal, Manju Monga

    Abstract:

    Abstract Objective: To determine whether prior knowledge of obstetric estimate of gestational age creates a bias in assignment of gestational age by the Ballard assessment score. Methods: The Ballard assessment score was done on 82 infants weighing less than 2500 g by two examiners, one who had prior knowledge of best obstetric gestational age estimate and the other who was masked to that information. Obstetric gestational age was correlated with masked and unmasked score. Statistical analysis used Spearman rank correlation test, plotting the measurement means against the measurement differences, χ2, Wilcoxon signed-rank test, analysis of variance, and Student t test. Significance was assumed at P Results: There was high reliability (r = 0.84–0.86) between obstetric gestational age estimates (33.3 ± 3.0 weeks) and the gestational age derived from masked (34.3 ± 3.0 weeks) and unmasked (34.0 ± 3.0 weeks) Ballard scores. The mean difference between unmasked scores and gestational age was 1.38 ± 1.15 weeks and that between masked scores and obstetric gestational age was 1.40 ± 1.15 weeks, a nonsignificant difference. There was no significant difference in the number of cases with 100% agreement between masked and unmasked scores and obstetric gestational age or in the number of cases in which the score (masked or unmasked) differed by more than 2 weeks from obstetric gestational age. This study had over 99% power to detect a 1-week difference between the accuracy of masked and unmasked scores. Conclusion: Prior knowledge of obstetric gestational age did not bias the Ballard assessment score.

  • Prior knowledge of obstetric gestational age and possible bias of Ballard score.
    Obstetrics and gynecology, 1999
    Co-Authors: Laurette N Smith, Vivek H Dayal, Manju Monga

    Abstract:

    To determine whether prior knowledge of obstetric estimate of gestational age creates a bias in assignment of gestational age by the Ballard assessment score.
    The Ballard assessment score was done on 82 infants weighing less than 2500 g by two examiners, one who had prior knowledge of best obstetric gestational age estimate and the other who was masked to that information. Obstetric gestational age was correlated with masked and unmasked score. Statistical analysis used Spearman rank correlation test, plotting the measurement means against the measurement differences, chi2, Wilcoxon signed-rank test, analysis of variance, and Student t test. Significance was assumed at P < .05.
    There was high reliability (r = 0.84-0.86) between obstetric gestational age estimates (33.3 +/- 3.0 weeks) and the gestational age derived from masked (34.3 +/- 3.0 weeks) and unmasked (34.0 +/- 3.0 weeks) Ballard scores. The mean difference between unmasked scores and gestational age was 1.38 +/- 1.15 weeks and that between masked scores and obstetric gestational age was 1.40 +/- 1.15 weeks, a nonsignificant difference. There was no significant difference in the number of cases with 100% agreement between masked and unmasked scores and obstetric gestational age or in the number of cases in which the score (masked or unmasked) differed by more than 2 weeks from obstetric gestational age. This study had over 99% power to detect a 1-week difference between the accuracy of masked and unmasked scores.
    Prior knowledge of obstetric gestational age did not bias the Ballard assessment score.