Polymeric Separator Synthesis for Lithium-Air Batteries

Battery electricity storage has been one of the main strategies to reach a sustainable energy network. They are adequate to store energy and release it later, supporting a high volume of variable renewable electricity. In this context, lithium-air batteries (LABs) have the potential to be a high-capacity battery option, with theoretical energy densities higher than currently available lithium-ion ones. However, they are still commercially unfeasible. In the last few decades, there has been immense progress in LABs technology with the development of stable electrolytes, porous cathodes, and catalysts. Nonetheless, minor attention has been given to the protection of the lithium metal electrode, especially against reactive substances present in the atmospheric air, such as water and oxygen. In this work, a protective membrane was synthesized to protect the metallic lithium anode against water. The synthesis was carried out using polytetramethylene glycol (PTMEG), 4,4-diphenylmethane diisocyanate (MDI), and a blend of 1,4 butanediol with glycerine as a chain extender. The synthesized membrane was tested using an aprotic lithium-oxygen (Li-O2) battery assembled with carbon paper as the cathode, metallic lithium as the anode, and 0.1 mol.L-1 lithium perchlorate (LiClO4) in dimethyl sulfoxide (DMSO) with 550 ppm of water concentration as electrolyte. Furthermore, the cyclability of the batteries with the novel polymeric membrane was compared with the standard glass microfiber separator. The results showed a higher cyclability of the batteries assembled with the polymeric separator over the glass microfiber separator.</p

DCC gene network in the prefrontal cortex is associated with total brain volume in childhood

BACKGROUND: Genetic variation in the guidance cue DCC gene is linked to psychopathologies involving dysfunction in the prefrontal cortex. We created an expression-based polygenic risk score (ePRS) based on the DCC coexpression gene network in the prefrontal cortex, hypothesizing that it would be associated with individual differences in total brain volume. METHODS: We filtered single nucleotide polymorphisms (SNPs) from genes coexpressed with DCC in the prefrontal cortex obtained from an adult postmortem donors database (BrainEAC) for genes enriched in children 1.5 to 11 years old (BrainSpan). The SNPs were weighted by their effect size in predicting gene expression in the prefrontal cortex, multiplied by their allele number based on an individual's genotype data, and then summarized into an ePRS. We evaluated associations between the DCC ePRS and total brain volume in children in 2 community-based cohorts: the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) and University of California, Irvine (UCI) projects. For comparison, we calculated a conventional PRS based on a genome-wide association study of total brain volume. RESULTS: Higher ePRS was associated with higher total brain volume in children 8 to 10 years old (β = 0.212, p = 0.043; n = 88). The conventional PRS at several different thresholds did not predict total brain volume in this cohort. A replication analysis in an independent cohort of newborns from the UCI study showed an association between the ePRS and newborn total brain volume (β = 0.101, p = 0.048; n = 80). The genes included in the ePRS demonstrated high levels of coexpression throughout the lifespan and are primarily involved in regulating cellular function. LIMITATIONS: The relatively small sample size and age differences between the main and replication cohorts were limitations. CONCLUSION: Our findings suggest that the DCC coexpression network in the prefrontal cortex is critically involved in whole brain development during the first decade of life. Genes comprising the ePRS are involved in gene translation control and cell adhesion, and their expression in the prefrontal cortex at different stages of life provides a snapshot of their dynamic recruitment

Testing the interaction of dark energy to dark matter through the analysis of virial relaxation of clusters Abell Clusters A586 and A1689 using realistic density profiles

Interaction between dark energy and dark matter is probed through deviation from the virial equilibrium for two relaxed clusters: A586 and A1689. The evaluation of the virial equilibrium is performed using realistic density profiles. The virial ratios found for the more realistic density profiles are consistent with the absence of interaction.Comment: 16pp 1 fig; accepted by GeR

Comparação do uso da pressão positiva com a fisioterapia convencional e incentivadores respiratórios após cirurgia cardíaca: revisão de literatura

Introduction: Postoperative pulmonary complications in patients undergoing cardiac surgeries are usually a clinical challenge, which can be prevented and treated with specific physical therapy techniques.However, it is not known which technique is the most effective. Objective: Literature review with theobjective of assessing the effectiveness of positive pressure (CPAP, IPPB, NIV-2P) compared to standardphysioterapy therapy and incentive spirometry on improving pulmonary function in postoperative cardiacsurgery patients. Methods: English and Portuguese studies were used as references, searching forspecific descriptors on the following data sources: BIREME, SciELO Brazil, LILACS, PUBMED, from 1985to 2010. Only randomized clinical trials were included. Results: Ten randomized control trials wereincluded in this review. About the most effective technique, two studies showed that CPAP and NIV-2Pwere more effective than standard physioterapy and incentive spirometry. In other two studies, NIV-2Pwere more effective than nasal oxygen catheter and standard physioterapy. Conclusion: There is noevidence in the literature about the most effective physiotherapy technique. Also, it is not known if theassociation of positive pressure, standard physioterapy and incentive spirometry can be more effective.It is important to emphasize that no selected study compared the three modalities of positive pressure.Introdução: No pós-operatório de cirurgia cardíaca frequentemente ocorrem complicações pulmonares, as quais podem ser prevenidas e tratadas com técnicas específicas de fisioterapia respiratória.Porém não se sabe qual a técnica mais efetiva. Objetivo: Revisão de literatura com o objetivo de verificara efetividade da pressão positiva (CPAP, VNI-2P, RPPI) comparada às técnicas de fisioterapia convencional e incentivador respiratório (IR) na recuperação da função pulmonar em pacientes no pós-operató-rio de cirurgia cardíaca. Métodos: Seleção de referências em inglês e português com descritores específicos ao tema nas seguintes fontes de dados: BIREME, SciELO Brazil, LILACS, PUBMED, de 1985 até2010. Foram incluídos apenas ensaios clínicos randomizados. Resultados: Dez ensaios clínicos randomizados foram incluídos para revisão. Em relação à superioridade de uma técnica sobre a outra, doisestudos verificaram que a modalidade CPAP e VNI-2P mostrou-se mais efetiva do que a fisioterapiaconvencional e o IR, enquanto que em dois outros estudos, demonstrou-se a superioridade da VNI-2P,em relação ao uso de cateter de oxigênio e à fisioterapia convencional. Apenas um estudo demonstroudiferença significativa ao comparar duas modalidades de pressão positiva, sendo a RPPI mais efetivaque a CPAP. Conclusão: Não há evidências acerca da melhor técnica a ser utilizada. Também não estáesclarecido se a associação da pressão positiva, fisioterapia convencional e IR poderia ser maisefetiva. Ressalta-se que nenhum dos estudos comparou simultaneamente as três modalidades depressão positiva