Abstract Extensive and severe droughts have substantial effects on water supplies, agriculture, aquatic ecosystems. To better understand these droughts, we used tree-ring-based reconstructions of the Palmer drought severity index (PDSI) for period 1475–2017 to examine that covered at least 33% conterminous United States (CONUS). We identified 37 spatially extensive events CONUS examined their s...

The predatory cone snails (Conus) are among the most successful living marine animals (;500 living species). Each Conus species is a specialist in neuropharmacology, and uses venom to capture prey, to escape from and defend against predators and possibly to deter competitors. An individual cone snail’s venom contains a diverse mixture of pharmacological agents, mostly small, structurally constr...

The origin of novel gene functions through gene duplication, mutation, and natural selection represents one of the mechanisms by which organisms diversify and one of the possible paths leading to adaptation. Nonetheless, the extent, role, and consequences of duplications in the origins of ecological adaptations, especially in the context of species interactions, remain unclear. To explore the e...

Spinal schwannomas are commonly intradural extramedullary in location. As Schwann cells are not common in the central nervous system, intramedullary schwannomas are a rare entity. In adults, an estimated sixty cases have been reported in English literature. They are rarer in children (less than ten cases), and preoperative diagnosis becomes a prerogative in achieving total excision. Cervical co...

Central arterial hemodynamics (blood pressure and velocity) as a function of ontogeny and season were determined in larval Rana catesbeiana (body mass 0.3-8.7 g, 20-22 degrees C). Ventricular systolic pressure increased from 1.8 mmHg at stage (St) II to 11.9 mmHg at St XIII, while ventricular diastolic pressures usually were less than 1.0 mmHg. In early stages (up to St V-VII) of fall/winter la...

Heart rate and blood pressure were measured in lightly anesthetized developing Xenopus laevis from hatching (body mass approximately 3 mg) to the end of metamorphosis (< or = 1 g). Blood pressures in the conus arteriosus, truncus arteriosus, and ventricle were measured by a servo-null micropressure system. Heart rate was determined from blood pressure recordings, and cardiac cycles were videota...

Forest covers about one-third of the land area conterminous United States (CONUS) and plays an important role in offsetting carbon emissions supporting local economies. Growing interest forests as relatively cost-effective nature-based climate solutions, particularly restoration reforestation activities has increased demand for information on forest regrowth recovery following natural anthropog...

Genes that encode products with exogenous targets, which comprise an organism's "exogenome," typically exhibit high rates of evolution. The genes encoding the venom peptides (conotoxins or conopeptides) in Conus sensu lato exemplify this class of genes. Their rapid diversification has been established and is believed to be linked to the high speciation rate in this genus. However, the molecular...

In order to investigate the evolution of conotoxin multigene families among two closely related vermivorous CONUS: species, we sequenced 104 four-loop conotoxin mRNAs from two individuals of CONUS: ebraeus and compared these with sequences already obtained from CONUS: abbreviatus. In contrast to the diversity of conotoxin sequences obtained from C. abbreviatus, only two common sequence variants...

The posttranslational gamma-carboxylation of glutamate residues in secreted proteins to gamma-carboxyglutamate is carried out by the vitamin K-dependent enzyme gamma-glutamyl carboxylase. gamma-Carboxylation has long been thought to be a biochemical specialization of vertebrates, essential for blood clotting. Recently, a gamma-carboxylase was shown to be expressed in Drosophila, although its fu...