Plasma Acylcarnitines during Pregnancy and Neonatal Anthropometry: A Longitudinal Study in a Multiracial Cohort

As surrogate readouts reflecting mitochondrial dysfunction, elevated levels of plasma acylcarnitines have been associated with cardiometabolic disorders, such as obesity, gestational diabetes, and type 2 diabetes. This study aimed to examine prospective associations of acylcarnitine profiles across gestation with neonatal anthropometry, including birthweight, birthweight z score, body length, sum of skinfolds, and sum of body circumferences. We quantified 28 acylcarnitines using electrospray ionization tandem mass spectrometry in plasma collected at gestational weeks 10–14, 15–26, 23–31, and 33–39 among 321 pregnant women from the National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singletons. A latent-class trajectory approach was applied to identify trajectories of acylcarnitines across gestation. We examined the associations of individual acylcarnitines and distinct trajectory groups with neonatal anthropometry using weighted generalized linear models adjusting for maternal age, race/ethnicity, education, parity, gestational age at blood collection, and pre-pregnancy body mass index (BMI). We identified three distinct trajectory groups in C2, C3, and C4 and two trajectory groups in C5, C10, C5–DC, C8:1, C10:1, and C12, respectively. Women with nonlinear decreasing C12 levels across gestation (5.7%) had offspring with significantly lower birthweight (−475 g; 95% CI, −942, −6.79), birthweight z score (−0.39, −0.71, −0.06), and birth length (−1.38 cm, −2.49, −0.27) than those with persistently stable C12 levels (94.3%) (all nominal p value < 0.05). Women with consistently higher levels of C10 (6.1%) had offspring with thicker sum of skinfolds (4.91 mm, 0.85, 8.98) than did women with lower levels (93.9%) during pregnancy, whereas women with lower C10:1 levels (12.6%) had offspring with thicker sum of skinfolds (3.23 mm, 0.19, 6.27) than did women with abruptly increasing levels (87.4%) (p < 0.05). In conclusion, this study suggests that distinctive trajectories of C10, C10:1, and C12 acylcarnitine levels throughout pregnancy were significantly associated with neonatal anthropometry.

Patterns and Persistence of Educational Mismatch: A Trajectory Approach Using Chilean Panel Data

The misalignment between workers’ educational levels and the educational level typically required for their occupations, namely educational mismatch, has become widespread. However, despite its potential costs, there is little evidence of this situation in developing countries. Using longitudinal and retrospective data of employment histories between 2009 and 2019, this paper conducts sequence analysis to construct a typology of educational mismatch trajectories among Chilean workers. We demonstrate that mismatch is a prevalent and persistent phenomenon. Once people enter the labor market, either as undereducated or overeducated workers, they tend to stay in such positions for extended periods of time. Moreover, we find significant wage penalties for workers in a mismatch situation. Results indicate that females and young, less-educated men are more prone to follow trajectories with longer periods of mismatch or unemployment. New avenues for research and the need for public policies looking at these phenomena are required to avoid people’s dissatisfaction due to a possible false promise that more education can improve their life standards.

Snow Water Equivalent Accumulation Patterns from a Trajectory Approach over the U.S. Southern Rocky Mountains

The spatial characteristics and patterns of snow accumulation and ablation inform the amount of water stored and subsequently available for runoff and the timing of snowmelt. This paper characterizes the snow accumulation phase to investigate the spatiotemporal snow water equivalent (SWE) distribution by fitting a function to the trajectory plot of the standard deviation versus mean SWE across a domain. Data were used from 90 snow stations for a 34-year period across the Southern Rocky Mountains in the western United States. The stations were divided into sub-sets based on elevation, latitude, and the mean annual maximum SWE. The best function was a linear fit, excluding the first 35 mm of SWE. There was less variability with SWE data compared to snow depth data. The trajectory of the accumulation phase was consistent for most years, with limited correlation to the amount of accumulation. These trajectories are more similar for the northern portion of the domain and for below average snow years. This work could inform where to locate new stations, or be applied to other earth system variables.

Plasma Acylcarnitines During Pregnancy and Neonatal Anthropometry: A Longitudinal Study in a Multiracial Cohort

Objectives Plasma profile of acylcarnitines has been suggested to associate with adverse maternal outcomes such as gestational diabetes. However, data on their associations with neonatal outcomes are sparse. Therefore, this study aimed to examine the prospective profile of acylcarnitines across gestation and its association with neonatal anthropometry, including birthweight (BW), BW z-score, the sum of skinfolds (SSF), length, and circumferences. Methods Among 321 pregnant women from the NICHD Fetal Growth Studies-Singletons cohort, we quantified 28 acylcarnitines using electrospray ionization tandem mass spectrometry in the plasma at gestational weeks 10–14, 15–26, 23–31 and 33–39, accordingly. We firstly applied a latent-class trajectory approach to identify trajectories of acylcarnitines across gestation, and secondly examined associations of individual acylcarnitine and distinct trajectory groups with neonatal anthropometry using weighted linear models with robust standard errors, adjusting for maternal age, race/ethnicity, education, parity, gestational week of blood collection, and pre-pregnancy body mass index. Results We identified three distinct trajectory groups of C2, C3 and C4, and two trajectory groups of C5, C10, C5-DC, C8:1, C10:1 and C12, respectively. Newborns of women with nonlinear decline of C12 levels across gestation (5.7%) had significantly smaller BW (−475 g; 95% CI: −942, −6.79 g), BW z-score (−0.39; −0.71, −0.06), and length (−1.38 cm; −2.49, −0.27 cm) than those with persistently stable C12 levels (94.3%). Newborns of women with consistently higher levels of C10 (6.1%) had greater sum of skinfolds (4.91 mm; 0.85, 8.98 mm) than those with lower levels (93.9%) across pregnancy, whereas newborns of women with declining C10:1 levels (12.6%) had larger sum of skinfolds (3.23 mm; 0.19, 6.27 mm) than those with abruptly increasing levels (87.4%). Conclusions In conclusion, gestational trajectories of C10, C10:1, and C12 acylcarnitine levels were significantly associated with neonatal anthropometry. Further studies are needed to verify and further explore the potential clinical utility of these findings. Funding Sources Eunice Kennedy Shriver National Institute of Child Health and Human Development intramural funding; American Recovery and Reinvestment Act funding.

A Multiple Power Reachable Sliding Mode Control Approach for Guidance of Miniature Laser Beam Riding Steered Munition

For a two-stage launch miniature shoulder munition steered with a laser beam riding system, the laser beam points to the target with a limited field radius and approximate straight-line spatial path; thus, the munition could not fly into the laser information field after the powered flight. The miniature munition dynamics are established firstly; then, an adaptive multiple power reachable sliding mode controller is presented and adopted to constrain both the trajectory inclination and pitch angle, which makes the munition enter the field and fly under control in the field with desired attitude angles, respectively. Considering the constraints of the incidence angle and the radius of the laser information field, an arctangent function curve is selected as the expected trajectory, and an adaptive multiple power reachable integral sliding mode guidance law is detailed, which makes the munition trajectory approach and converges to the expected curve fastly with limited acceleration. Therefore, the miniature munition flight trajectory is planned and optimized. Convergence and stability are analyzed based on the Lyapunov method. The numerical simulation against the stationary target is performed to fully demonstrate the efficacy of the proposed method.

Abstract P166: Plasma Acylcarnitines During Pregnancy And Neonatal Anthropometry: A Prospective And Longitudinal Study

As surrogate readouts reflecting tissue acyl-CoA pools, elevated levels of plasma acylcarnitines have been associated with cardiometabolic disorders, such as obesity, gestational diabetes, and type 2 diabetes. This study aimed to examine prospective associations of acylcarnitine profiles across gestation with neonatal anthropometry, including birthweight (BW), BW z-score, the sum of skinfolds (SS), body length, and head circumference. We quantified 28 acylcarnitines using electrospray ionization tandem mass spectrometry in plasma collected at gestational weeks 10-14, 15-26, 23-31 and 33-39 among 321 pregnant women from the NICHD Fetal Growth Studies-Singletons and performed latent-class trajectory approach to identify trajectories of acylcarnitines across gestation. We examined the associations of individual acylcarnitines and distinct trajectory groups with neonatal outcomes using weighted generalized linear models adjusting for maternal age, race, education, parity, gestational age of blood collection, and pre-pregnancy BMI. Women showed changes in plasma levels of all acylcartinines across gestation and had at least two significantly distinct group-based trajectories for 32% of acylcartinines. Longitudinally, women with increased C12 levels across gestation (5.7%) had significantly smaller BW (-475 g; 95% CI, -942, -6.79), BW z-score (-0.39, 95% CI, -0.71, -0.06), and length (-1.38, 95% CI, -2.49, -0.27) than those with persistently stable C12 levels during pregnancy (all FDR<0.05). Women with persistently higher levels of C10 (6.1%) or C10:1 (87.4%) had greater sum of skinfolds (4.91, 95%, 0.85, 8.98) than those with lower levels during pregnancy (P<0.05). In conclusion, this study identified that gestational trajectories of C10, C10:1, and C12 acylcarnitine levels were significantly associated with neonatal anthropometry. Further studies are needed to replicate and assess clinical utility of these findings.