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© 2002 The American Physical Society. We thank Professor Ivan Schuller for helpful conversations and interesting suggestions. This work was supported by Spanish CICYT MAT 2000 1468. Work at LBNL/NCEM was supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098., We report on the growth mechanism of YBa_(2)Cu_(3)O_(7-x). Our study is based on an analysis of ultrathin YBa_(2)Cu_(3)O_(7-x) (YBCO) layers in c-axis-oriented YBa_(2)Cu_(3)O_(7-x)/PrBa_(2)Cu_(3)O_(7)superlattices. We have found that the release of epitaxial strain in very thin YBCO layers triggers a change in the dimensionality of the growth mode. Ultrathin epitaxially strained YBCO layers with thickness below 3 unit cells grow in a blockby-block two -dimensional mode that is coherent over large lateral distances. Meanwhile, when the thickness increases and the strain relaxes, layer growth turns three-dimensional, resulting in rougher layers and interfaces., Spanish CICYT, Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2010 The American Physical Society. We acknowledge financial support by Junta de Comunidades de Castilla-La Mancha through Project No. PAI-05- 013, by CAM under Grant No. S2009/MAT-1756 Phama, by Spanish MICINN through Grants No. MAT2008-06517- C02, No. MAT2008-06542-C04, and No. FIS2009-12964- C05-04, and Consolider Ingenio 2010 under Grant No. CSD2009-00013 Imagine. We thank J. Garcia-Barriocanal for helpful discussions. We are indebted to the staff of SpLine for their help during the experimental work at ESRF., We report on the effect of grain size on the ionic conductivity of yttria-stabilized zirconia samples synthesized by ball milling. Complex impedance measurements, as a function of temperature and frequency are performed on 10 mol % yttria-stabilized zirconia nanocrystalline samples with grain sizes ranging from 900 to 17 nm. Bulk ionic conductivity decreases dramatically for grain sizes below 100 nm, although its activation energy is essentially independent of grain size. The results are interpreted in terms of a space-charge layer resulting from segregation of mobile oxygen vacancies to the grain-boundary core. The thickness of this space-charge layer formed at the grain boundaries is on the order of 1 nm for large micron-sized grains but extends up to 7 nm when decreasing the grain size down to 17 nm. This gives rise to oxygen vacancies depletion over a large volume fraction of the grain and consequently to a significant decrease in oxide-ion conductivity., Junta de Comunidades de Castilla-La Mancha, CAM, Spanish MICINN, Consolider Ingenio 2010, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

The progressive industrialization has resulted in an increase in heavy metal pollution in the environment, which has a dangerous impact on human health. Prenatal exposure to heavy metals, even at very low concentrations, may be especially harmful to pregnant women and their children. Different industrial activities can contribute to heavy metal pollution in a specific area.1) To explore the concentrations of heavy metals in urine samples of pregnant women, and 2) to evaluate the potential effect of different industrial activities in Tarragona (Spain).Urinary levels of four heavy metals (nickel (Ni), cadmium (Cd), mercury (Hg), and lead (Pb)) from 368 pregnant women recruited in the ECLIPSES study were analyzed. Home addresses and all the industries potentially releasing heavy metals were geo-referenced. Buffer zones were established within a 1.5, 3, and 5 km radius at the center of each industry. Subsequently, the number of participants living in and out of each buffer zone was recorded.Urinary levels of Ni and Cd, but not those of Hg and Pb, were obviously increased in pregnant women living near most of the industrial sites. After adjustment for potential co-variates, only Cd showed notable differences according to the industrial activity. Compared to women living outside the buffer, Cd levels were increased in those living within 1.5 and 3 km of chemical industries, within 5 km of energy industries, within 1.5, 3, and 5 km of mineral industries, and within 3 and 5 km of metal processing industries.Among the analyzed heavy metals, Cd showed an increasing trend in urinary concentrations in women living near chemical, energy, mineral, and metal processing industries. This study highlights the need to develop legislative measures to minimize Cd exposure, especially by sen

Introduction: The effectiveness of prenatal iron supplementation improves maternal hematological outcomes, but little research has focused on child outcomes. The objective of this study was to assess whether prenatal iron supplementation adjusted to maternal needs improves children's cognitive functioning. Methods: The analyses included a subsample of nonanemic pregnant women recruited in early pregnancy and their children aged 4 years (n=295). Data were collected between 2013 and 2017 in Tarragona (Spain). On the basis of hemoglobin levels before the 12th gestational week, women receive different iron doses: 80 vs 40 mg/d if hemoglobin is 110–130 g/L and 20 vs 40 mg/d if hemoglobin >130 g/L. Children's cognitive functioning was assessed using the Wechsler Preschool and Primary Scale of Intelligence-IV and Developmental Neuropsychological Assessment-II tests. The analyses were carried out in 2022 after the completion of the study. Multivariate regression models were performed for assessing the association between different doses of prenatal iron supplementation and children's cognitive functioning. Results: Taking 80 mg/d of iron was positively associated with all the scales of the Wechsler Preschool and Primary Scale of Intelligence-IV and Neuropsychological Assessment-II when mothers had initial serum ferritin <15 µg/L, but it was negatively associated with Verbal Comprehension Index, Working Memory Index, Processing Speed Index, and Vocabulary Acquisition Index from Wechsler Preschool and Primary Scale of Intelligence-IV and verbal fluency index from Neuropsychological Assessment-II when mothers showed initial serum ferritin >65 µg/L. In the other group, taking 20 mg/d of iron was positively associated with Working Memory Index, Intelligence Quotient, verbal fluency

Several population-specific genetic, sociodemographic, and maternal lifestyle factors are related to iron status in early pregnancy, and their identification would allow preventive actions to be taken. The study aimed to identify maternal factors associated with iron deficiency (ID) in early pregnancy in non-anaemic pregnant women from a European Mediterranean country. Cross-sectional study using the initial population of the ECLIPSES study performed in non-anaemic pregnant women before gestational week 12. Serum ferritin (SF) and haemoglobin concentrations were measured to evaluate iron status, and ID was defined as SF < 15 µg/L. Several sociodemographic and lifestyle data were recorded and used as covariates in the multivariate-adjusted regression models. Out of the 791 participants, 13.9% had ID in early pregnancy. Underweight (OR 3.70, 95%CI 1.22, 15.53) and parity (1 child: OR 2.03, 95%CI 1.06, 3.88; ≥ 2 children: OR 6.96, 95%CI 3.09, 15.69) increased the odds of ID, while a high intake of total meat (≥ 108.57 g/day: OR 0.37, 95%CI 0.15, 0.87), red/processed meat (≥ 74.29 g/day: OR 0.70, 95%CI 0.35, 0.98), protein (≥ 65.05 g/day: OR 0.85, 95%CI 0.30, 0.99), and dietary iron (≥ 8.58 mg/day: OR 0.58, 95%CI 0.35, 0.94) protected against it. Smoking was also associated with a reduction in ID odds (OR 0.34, 95%CI 0.12, 0.99). Baseline BMI, parity, smoking, and diet are associated with ID in early pregnancy in non-anaemic women. Pregnancy planning policies should focus on women at higher risk of ID, such as those who are underweight, multiparous, or following vegetarian diets. This clinical trial was registered at www.clinicaltrialsregister.eu as EudraCT number 2012-005,480-28 and at www.clinicaltrials.gov with identification number NCT03196882.© 2023. The Author(s).