Ante- and intrapartum risk factors for neonatal hypoxic ischemic encephalopathy.

PURPOSE: To identify obstetrical risk factors for the diagnosis of neonatal hypoxic ischemic encephalopathy (HIE). A secondary aim was to determine the incidence of HIE. MATERIALS AND METHODS: A retrospective cohort study including 36,086 women with singleton term pregnancies giving live births in Sweden between 2009 and 2013. Cases of HIE were identified from three different sources. Risk factors for HIE were evaluated using univariate and multivariate analyses. Cases of HIE were extracted from available Swedish Medical Health registers to determine incidence. RESULTS: A diagnosis of HIE was associated with: acute obstetrical events, mode of delivery other than unassisted vaginal birth, abnormal CTG admission test, and nulliparity. The incidence of HIE was 1.7/1000 infants born. CONCLUSIONS: Acute obstetrical events will always occur, and some of the risk factors for these events are not responsive to interventions, but a careful risk assessment could lower the risk associated with acute obstetrical events. By alertness to early symptoms and timely measures taken by a trained staff at the delivery unit, damage could be reduced.

Antagonistic natural and sexual selection on wing shape in a scrambling damselfly.

Wings are a key trait underlying the evolutionary success of birds, bats, and insects. For over a century, researchers have studied the form and function of wings to understand the determinants of flight performance. However, to understand the evolution of flight, we must comprehend not only how morphology affects performance, but also how morphology and performance affect fitness. Natural and sexual selection can either reinforce or oppose each other, but their role in flight evolution remains poorly understood. Here, we show that wing shape is under antagonistic selection with regard to sexual and natural selection in a scrambling damselfly. In a field setting, natural selection (survival) favored individuals with long and slender forewings and short and broad hindwings. In contrast, sexual selection (mating success) favored individuals with short and broad forewings and narrow-based hindwings. Both types of selection favored individuals of intermediate size. These results suggest that individuals face a trade-off between flight energetics and maneuverability and demonstrate how natural and sexual selection can operate in similar directions for some wing traits, that is, wing size, but antagonistically for others, that is, wing shape. Furthermore, they highlight the need to study flight evolution within the context of species' mating systems and mating behaviors.

Reaction of singlet-excited 2,3-diazabicyclo[2.2.2]oct-2-ene and tert-butoxyl radicals with aryl-substituted benzofuranones.

5,7-Di-tert-butyl-3-aryl-3H-benzofuran-2-ones are lactones with potential antioxidant activity, owing to their abstractable benzylic C-H hydrogens. The fluorescence quenching of the azoalkane 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO), an established probe for the hydrogen-donor propensity of chain-breaking antioxidants, was investigated for 16 aryl-substituted benzofuranone derivatives [m,m-(CF3)2, p-CN, m-CN, p-CF3, p-COOCH3, m-CF3, p-Cl, p-F, H, m-CH3, p-CH3, m,p-(CH3)2, p-OCH3, o-CH3, o-CF3, o,m-(CH3)2]. Analysis of the rate data in terms of a linear free energy relationship yielded a reaction constant of rho = +0.35. This implies that n,pi*-excited DBO acts as nucleophilic species. In contrast, hydrogen abstraction of tert-butoxyl radicals from the benzofuranones was accelerated by electron-donating substituents (rho = -0.23), in conformity with the electrophilic character of oxygen-centered alkoxyl radicals. Possible implications for the optimization of the hydrogen-donor propensity of antioxidants through structural variation are discussed.