O impacto do modelo de parteira em gravidez de baixo risco: a experiência internacional

Verificar se o modelo de parteira em gravidez de baixo risco diminui as intervenções médicas durante o parto. Identificar se modelo de parteira em gravidez de baixo risco com seguimento pelo mesmo especialista ou grupos de especialistas resulta num empoderamento da mulher grávida. Metodologia: foi realizada uma revisão da literatura através das bases de dados PubMed e Cochrane, com os descritores: caseload midwidery, gravidez de baixo risco e parto da qual resultaram 11 artigos em língua inglesa e portuguesa. Após leitura dos resumos e apreciação geral dos estudos emergiram para análise final 6 artigos em língua inglesa. Resultados: apurou-se a existência de uma correlação significativa na diminuição de intervenções médicas tais como partos instrumentados, partos cirúrgicos (p<0,001), uso de analgesia regional (p<0,001), tal como uso de epidural e realização quer de amniotomia quer de episiotomia. Também se identificou uma maior satisfação das utentes seguidas pelo modelo de parteira relativamente à experiência de parto, em que as utentes referem que se sentiram menos ansiosas, mais empoderadas e com maior probabilidade de ter uma experiência mais positiva em relação à dor de parto. Conclusões: as conclusões dos estudos refletem a realidade dos serviços de saúde no Reino Unido e Austrália, onde a enfermeira especialista em saúde materna e obstetrícia realiza a vigilância de gravidezes de baixo risco e parto. Tendo em consideração os resultados dos estudos anteriormente referidos seria importante o desenvolvimento e aplicação de um projeto piloto para avaliar a eficácia dos resultados obtidos na população portuguesa.info:eu-repo/semantics/publishedVersio

Enhanced Photovoltaic Performance Of Inverted Hybrid Bulk-heterojunction Solar Cells Using Tio2/reduced Graphene Oxide Films As Electron Transport Layers

In this study, we investigated inverted hybrid bulk-heterojunction solar cells with the following configuration: fluorine-doped tin oxide (FTO) jTiO2/RGOjP3HT:PC61BMjV2O5 or PEDOT:PSS|Ag. The TiO2/GO dispersions were prepared by sol-gel method, employing titanium isopropoxide and graphene oxide (GO) as starting materials. The GO concentration was varied from 0.1 to 4.0 wt%. The corresponding dispersions were spin-coated onto FTO substrates and a thermal treatment was performed to remove organic materials and to reduce GO to reduced graphene oxide (RGO). The TiO2/RGO films were characterized by X-ray diffraction, Raman spectroscopy, and microscopy techniques. Atomic force microscopy (AFM) images showed that the addition of RGO significantly changes the morphology of the TiO2 films, with loss of uniformity and increase in surface roughness. Independent of the use of V2O5 or PEDOT: PSS films as the hole transport layer, the incorporation of 2.0 wt% of RGO into TiO2 films was the optimal concentration for the best organic photovoltaic performance. The solar cells based on TiO2/RGO (2.0 wt%) electrode exhibited a ~22.3% and ~28.9% short circuit current density (Jsc) and a power conversion efficiency enhancement, respectively, if compared with the devices based on pure TiO2 films. Kelvin probe force microscopy images suggest that the incorporation of RGO into TiO2 films can promote the appearance of regions with different charge dissipation capacities.51Hau, S.K., Yip, H.L., Jen, A.K.Y., A review on the development of the inverted polymer solar cell architecture (2010) Polym. Rev., 50 (4), pp. 474-510Liang, Y.Y., For the bright future-bulk heterojunction polymer solar cells with power conversion efficiency of 7.4% (2010) Adv. 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