Membrane Distillation: Pre-Treatment Effects on Fouling Dynamics.

In the research reported in this paper, membrane distillation was employed to recover water from a concentrated saline petrochemical effluent. According to the results, the use of membrane distillation is technically feasible when pre-treatments are employed to mitigate fouling. A mathematical model was used to evaluate the fouling mechanism, showing that the deposition of particulate and precipitated material occurred in all tests; however, the fouling dynamic depends on the pre-treatment employed (filtration, or filtration associated with a pH adjustment). The deposit layer formed by particles is not cohesive, allowing its entrainment to the bulk flow. The precipitate fouling showed a minimal tendency to entrainment. Also, precipitate fouling served as a coupling agent among adjacent particles, increasing the fouling layer cohesion.

Maternal preeclampsia protects preterm infants against severe retinopathy of prematurity.

OBJECTIVE: To study the influence of maternal preeclampsia on the occurrence of retinopathy of prematurity. STUDY DESIGN: A prospective cohort study of 324 preterm neonates with birth weight ≤ 1500 g and gestational age ≤ 32 weeks. Multiple maternal and perinatal factors were analyzed for association and confounding by multiple logistic regression analysis. RESULTS: Mean birth weight was 1128 ± 240 g, and mean gestational age 29.7 ± 1.9 weeks. Twenty-four newborns (7.4%) had severe retinopathy of prematurity; 97 had any stage of retinopathy, and 227 had no retinopathy of prematurity. Preeclampsia and complete antenatal steroid treatment course reduced the risk for any stage of retinopathy of prematurity by 60% and 54%, respectively. Preeclampsia reduced the risk for severe retinopathy of prematurity by 80%. CONCLUSIONS: Preeclampsia lowered the risk for occurrence of any stage and severe retinopathy of prematurity in very low birth weight infants.

Asma pré-menstrual: realidade ou ficção? / Premenstrual asthma: reality or fiction?

A asma pré-menstrual foi descrita pela primeira vez no princípio do século passado e, desde então, muito se tem pesquisado a respeito desta patologia Esta se apresenta com os sinais clássicos de hiper-responsividade brônquica, aumento da secreção e constrição da musculatura, porém, chama a atenção sua relação com o período menstrual. Este trabalho propõe uma revisão atualizada da literatura, a fim de chamar a atenção do médico para sua ocorrência e ressaltar a importância de futuras investigações sobre o tema.

The premenstrual asthma was described for the firs time at the beginning of the last century and after that a lot have been worked about that. Fisipathology is the same of the classical asthma (bronquial hyperreactivity, increase production of secretion and muscular constriction), but with a special link with menstrual period. This paper is a review of the literature, with the purpose of make physicians think about it and stimulate research about it.