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This paper studies the dynamics and stability of a stage-structured (immature/mature) population. The emphasis is on how resource available to the immature stage indirectly regulates the dynamics of the mature stage, where the resource is defined by a Holling-II function. We present the results from numerical experiments, where inference about stability and predictability of the system dynamics is based on the theory of Lyapunov exponents.

Purpose Limited research has focused on the association between prenatal thyroid hormone replacement therapy (THRT) and motor function, communication skills, and behavior in preschool children. Here, we estimated the association between THRT during pregnancy and the first trimester and these developmental outcomes. Methods: This study was based on the Norwegian Mother, Father, and Child Cohort Study (MoBa) and other national registries. We included mother–child pairs exposed to THRT during pregnancy (n = 663), after delivery (n = 728), or unexposed (n = 28 040). Exposure to THRT was defined according to filled prescriptions. Child outcomes, presented as T‐score differences, were parent‐reported using the Ages and Stages Questionnaire, Strengths and Difficulties Questionnaire, and Child Behavior Checklist. Results: Of 29 431 mother–child pairs, 2.3% were prenatally exposed to THRT. We found no difference between prenatally exposed and unexposed children in regards to gross motor function (β: 0.17, 95% CI −1.19, 1.54), fine motor function (β: −0.17, 95% CI −1.14, 0.80), communication (β: −0.31, 95% CI −1.58, 0.96), externalizing (β: −0.03, 95% CI −1.07, 1.01), internalizing (β: 0.89, 95% CI −0.20, 1.97), or social behaviors (β: −0.04, 95% CI −0.92, 0.84). Somatic complaints were higher in THRT‐exposed children (β: 0.98, 95% CI 0.08, 1.87), and children whose mothers were exposed after delivery had more sleep problems than unexposed children (β: 0.99, 95% CI 0.24, 1.74). Conclusions: Children prenatally exposed to THRT have developmental outcomes as positive as unexposed children on motor function, communication, and behavior. The association with somatic complaints and sleep were not clinically relevant. [ABSTRACT FROM AUTHOR]

The dynamics of marine populations are usually forced by biotic and abiotic factors occurring at different intensity levels and time scales. Deriving the time frame within which each factor has a causal influence is important for predicting population trajectories. This paper presents a statistical methodology for establishing (i) the strength of causal coupling between population dynamics and environmental (biotic and abiotic) factors, and (ii) the time scales over which causal covariates have significant influence on the population dynamics. The methodology is based on combining a multivariate autoregressive model fit to data (to determine causal direction) with a quantification of the RPC of covariates in frequency domain (to quantify the strength of connection). The methodology is applied to test the existence of causal coupling between the capelin biomass and a selected number of covariates identified in the literature. [ABSTRACT FROM AUTHOR]

Purpose: Limited research has focused on the association between prenatal thyroid hormone replacement therapy (THRT) and motor function, communication skills, and behavior in preschool children. Here, we estimated the association between THRT during pregnancy and the first trimester and these developmental outcomes., Methods: This study was based on the Norwegian Mother, Father, and Child Cohort Study (MoBa) and other national registries. We included mother-child pairs exposed to THRT during pregnancy (n = 663), after delivery (n = 728), or unexposed (n = 28 040). Exposure to THRT was defined according to filled prescriptions. Child outcomes, presented as T-score differences, were parent-reported using the Ages and Stages Questionnaire, Strengths and Difficulties Questionnaire, and Child Behavior Checklist., Results: Of 29 431 mother-child pairs, 2.3% were prenatally exposed to THRT. We found no difference between prenatally exposed and unexposed children in regards to gross motor function (β: 0.17, 95% CI -1.19, 1.54), fine motor function (β: -0.17, 95% CI -1.14, 0.80), communication (β: -0.31, 95% CI -1.58, 0.96), externalizing (β: -0.03, 95% CI -1.07, 1.01), internalizing (β: 0.89, 95% CI -0.20, 1.97), or social behaviors (β: -0.04, 95% CI -0.92, 0.84). Somatic complaints were higher in THRT-exposed children (β: 0.98, 95% CI 0.08, 1.87), and children whose mothers were exposed after delivery had more sleep problems than unexposed children (β: 0.99, 95% CI 0.24, 1.74)., Conclusions: Children prenatally exposed to THRT have developmental outcomes as positive as unexposed children on motor function, communication, and behavior. The association with somatic complaints and sleep were not clinically relevant., (© 2020 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons Ltd.)