Publications by authors named "Alberto Mejia"

Objectives: To validate intraplacental villous artery (IPVA) Doppler as a predictor for placenta-mediated diseases (PMDs), to compare its predictive value with uterine artery (UtA) Doppler and placental biochemical markers, and to assess its value in predictive PMD models.

Methods: IPVA and UtA indices (pulsatility index [PI] and resistance index [RI]) were recorded at 18-24 weeks of gestation in a cohort of 117 women. The predictive values of IPVA, UtA, and placental biochemical markers were analyzed and compared between the PMD group (the women who developed preeclampsia or intrauterine growth restriction) and the non-PMD group (the women who remained healthy throughout pregnancy and 3 months postpartum) using the receiver-operating characteristic curves.

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In the study of the electric properties of electrolytes, the determination of the diffusion coefficients of the species that intervene in the charge transport process is of great importance, particularly that of the free ions (D(+) and D(-)), the only species that contribute to the conductivity. In this work we propose a model that allows, with reasonable assumptions, determination of D(+) and D(-), and the degree of dissociation of the salt, α, at different concentrations, using the diffusion coefficients experimentally obtained with NMR. Also, it is shown that the NMR data suffice to estimate the conductivity of the electrolytes.

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