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1.
ACS Comb Sci ; 20(7): 451-460, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29878748

RESUMO

High-throughput techniques have been employed for the synthesis and characterization of thin film phosphors of Eu-doped Ba xSr2- xSiO4. Direct synthesis from evaporation of the constituent elements under a flux of atomic oxygen on a sapphire substrate at 850 °C was used to directly produce thin film libraries (415 nm thickness) of the crystalline orthosilicate phase with the desired compositional variation (0.24 > x > 1.86). The orthosilicate phase could be synthesized as a pure, or predominantly pure, phase. Annealing the as synthesized library in a reducing atmosphere resulted in the reduction of the Eu while retaining the orthosilicate phase, and resulted in a materials thin film library where fluorescence excited by blue light (450 nm) was observable by the naked eye. Parallel screening of the fluorescence from the combinatorial libraries of Eu doped Ba xSr2- xSiO4 has been implemented by imaging the fluorescent radiation over the library using a monochrome digital camera using a series of color filters. Informatics tools have been developed to allow the 1931 CIE color coordinates and the relative quantum efficiencies of the materials library to be rapidly assessed and mapped against composition, crystal structure and phase purity. The range of compositions gave values of CIE x between 0.17 and 0.52 and CIE y between 0.48 and 0.69 with relative efficiencies in the range 2.0 × 10-4-7.6 × 10-4. Good agreement was obtained between the thin film phosphors and the fluorescence characteristics of a number of corresponding bulk phosphor powders. The thermal quenching of fluorescence in the thin film libraries was also measured in the temperature range 25-130 °C: The phase purity of the thin film was found to significantly influence both the relative quantum efficiency and the thermal quenching of the fluorescence.


Assuntos
Bário/química , Técnicas de Química Combinatória/métodos , Európio/química , Substâncias Luminescentes/química , Samário/química , Silício/química , Bibliotecas de Moléculas Pequenas/química , Óxido de Alumínio/química , Temperatura Alta , Luz , Medições Luminescentes/métodos , Óxidos/química , Oxigênio/química , Bibliotecas de Moléculas Pequenas/síntese química
2.
Am J Obstet Gynecol ; 197(3): 244.e1-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17826405

RESUMO

OBJECTIVE: The objective of the study was to evaluate angiogenic factors for the prediction of preeclampsia in high-risk women. STUDY DESIGN: We collected serial serum specimens from 94 women at high preeclampsia risk between 22 and 36 weeks' gestation. Soluble fms-like tyrosine kinase-1 (sFlt1) and placental growth factor (PlGF) were measured by enzyme-linked immunosorbent assay. RESULTS: Mean serum sFlt1 and the sFlt1/PlGF ratio were higher in subjects who developed early-onset (less than 34 weeks) preeclampsia, as compared with subjects without preeclampsia, from 22 weeks gestation onward. In subjects who developed late-onset (34 weeks or later) preeclampsia, sFlt1 was significantly increased after 31 weeks' gestation. The sFlt1/PlGF ratio at 22-26 weeks was highly predictive of early-onset preeclampsia. The within-woman rate of change of the sFlt1/PlGF ratio was predictive of overall preeclampsia risk. CONCLUSIONS: In high-risk women, serum sFlt1 and the sFlt1:PlGF ratio are altered prior to preeclampsia onset and may be predictive of preeclampsia. Larger studies are needed to confirm these findings.


Assuntos
Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Proteínas da Gravidez/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Indutores da Angiogênese/sangue , Biomarcadores/sangue , Feminino , Humanos , Fator de Crescimento Placentário , Valor Preditivo dos Testes , Gravidez , Gravidez de Alto Risco/sangue , Estudos Prospectivos
3.
Int J Gynaecol Obstet ; 134(1): 93-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27126905

RESUMO

OBJECTIVE: To evaluate the effects of a mobile phone-based intervention on postnatal maternal health behavior and maternal and infant health in a middle-income country. METHODS: A prospective evaluation enrolled consecutive postpartum women at two public hospitals in Quito, Ecuador, between June and August 2012. Inclusion criteria were live birth, no neonatal intensive care admission, and Spanish speaking. Intervention and control groups were assigned via random number generation. The intervention included a telephone-delivered educational session and phone/text access to a nurse for 30days after delivery. Maternal and infant health indicators were recorded at delivery and 3months after delivery via chart review and written/telephone-administered survey. RESULTS: Overall, 102 women were assigned to the intervention group and 76 to the control group. At 3months, intervention participants were more likely to attend the infant's postnatal check-up (P=0.022) and to breastfeed exclusively (P=0.005), and less likely to feed formula (P=0.016). They used more effective forms of contraception (more implants P=0.023; fewer condoms P=0.036) and reported fewer infant illnesses (P=0.010). There were no differences in maternal acute illness or check-up attendance. CONCLUSION: Mobile phone-based postnatal patient education is a promising strategy for improving breastfeeding, contraceptive use, and infant health in low-resource settings; different strategies are needed to influence postpartum maternal health behavior.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Telefone Celular/estatística & dados numéricos , Comportamento Contraceptivo/estatística & dados numéricos , Saúde do Lactente/normas , Saúde Materna/normas , Período Pós-Parto , Adulto , Criança , Equador , Feminino , Humanos , Recém-Nascido , Estudos Prospectivos , Inquéritos e Questionários , Adulto Jovem
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