Accelerated biotic turnover during the Late Triassic has led to the perception of an end-Triassic mass extinction event, now regarded as one of the ‘‘big five’’ extinctions. Close examination of the fossil record reveals that many groups thought to be affected severely by this event, such as ammonoids, bivalves and conodonts, instead were in decline throughout the Late Triassic, and that other ...

Approximately 50 ka, one or more subgroups of modern humans expanded from Africa to populate the rest of the world. Significant behavioral change accompanied this expansion, and archaeologists commonly seek its roots in the African Middle Stone Age (MSA; ∼200 to ∼50 ka). Easily recognizable art objects and "jewelry" become common only in sites that postdate the MSA in Africa and Eurasia, but so...

Introduction Induction of labor is increasing. A common indication for induction late term and postterm pregnancy at 41 weeks or more. We aimed to evaluate if there are any differences regarding efficacy, safety, women's childbirth experience between oral misoprostol transvaginal balloon catheter cervical ripening in women with a low-risk singleton 41+0 42+0 1 gestation. Material methods In thi...

The molecular evolution of the leukotoxin structural gene (lktA) of Mannheimia (Pasteurella) haemolytica was investigated by nucleotide sequence comparison of lktA in 31 bovine and ovine strains representing the various evolutionary lineages and serotypes of the species. Eight major allelic variants (1.4 to 15.7% nucleotide divergence) were identified; these have mosaic structures of varying de...

One of the most remarkable examples of convergent evolution among vertebrates is illustrated by the independent origins of an active electric sense in South American and African weakly electric fishes, the Gymnotiformes and Mormyroidea, respectively. These groups independently evolved similar complex systems for object localization and communication via the generation and reception of weak elec...

OBJECTIVES To assess the effects of non-communicable diseases, such as diabetes, hypertension and obesity, on the mother and the infant. METHODS A multicentre cohort study was conducted in three hospitals in the city of Riyadh in Saudi Arabia. All Saudi women and their babies who delivered in participating hospitals were eligible for recruitment. Data on socio-demographic characteristics in a...

Venous air embolism is the entrapment of air into the venous system producing signs and symptoms due to obstruction of pulmonary arterial blood flow. We present a healthy, 27-year-old, full-term parturient admitted for postdate induction of labor. Cesarean delivery was required following fetal distress. During delivery, the mother became bradycardic and required advanced cardiac life support fo...

The Paleocene-Eocene Thermal Maximum (PETM) (∼56 Ma) was a ∼170,000-y (∼170-kyr) period of global warming associated with rapid and massive injections of 13C-depleted carbon into the ocean-atmosphere system, reflected in sedimentary components as a negative carbon isotope excursion (CIE). Carbon cycle modeling has indicated that the shape and magnitude of this CIE are generally explained by a l...

The 3.43 billion-year-old Strelley Pool Chert, Pilbara Craton, Western Australia, contains compelling evidence of Early Archaean life in the form of kilometre-sized remnants of an ancient stromatolitic carbonate platform. Reviewing and building on earlier studies, we examine the fossilized remains of the platform to seek ecosystem-scale insights to Earth’s early biosphere, examining the evidenc...

River channels and valleys have been observed on several planetary bodies in addition to the Earth. Long sinuous valleys on Venus, our Moon and Jupiter's moon Io are clearly formed by lava, and branching valleys on Saturn's moon Titan may be forming today by rivers of methane. But by far the most dissected body in our Solar System apart from the Earth is Mars. Branching valleys that in plan res...