Forearm skin of Stage XXIV Rana pipiens, which cannot regenerate limbs, was removed and placed upon the skinned forearms of young axolotls. The axolotl limbs were amputated immediately through the level of the grafts. Frog epidermis migrated to cover the amputation surface. Dedifferentiation and early blastema formation occurred beneath the frog wound epidermis. Limb regeneration continued, but...

We discuss the use of second-harmonic generation (SHG) as the nonlinearity in the technique of frequencyresolved optical gating (FROG) for measuring the full intensity and phase evolution of an arbitrary ultrashort pulse. FROG that uses a third-order nonlinearity in the polarization-gate geometry has proved extremely successful, and the algorithm required for extraction of the intensity and the...

Introduction Raising and selling frogs on a commercial basis has not proven to be successful economically in Virginia or elsewhere in the United States to our knowledge. Although farming for frog legs sounds promising, operating a profitable frog farm seems to be more of a myth than a reality. Those few individuals who claim to be successful frog farmers generally are distributors engaged in th...

Ranaviruses have been associated with most of the reported larval anuran die-offs in the United States. It is hypothesized that anthropogenically induced stress may increase pathogen prevalence in amphibian populations by compromising immunity. Cattle use of wetlands may stress resident tadpole populations by reducing water quality. We isolated a Ranavirus from green frog Rana clamitans (n = 80...

Avian incubation attentiveness has important fitness consequences through its influence on the number and quality of hatched young and energetic costs imposed on parents. Nest attentiveness is highly variable across species and geographic regions. We reviewed the literature and show a worldwide pattern that nest attentiveness is generally lower in southern compared with northem-latitude passeri...

Based on a single observation some evidence is presented suggesting that predation of Hamilton's frog by tuatara is occurring on Stephens Island, 40<> 40' S, 174 <>00' E in Cook Strait, Bones of the left hind limb of a frog were identified from a tuatara dropping collected from the frogs' habitat. Because of the tenuous state of the island's frog population, factors thought to limit the inciden...

Introduction: Effects of melatonin (MT) were comparatively examined on melanophores of isolated skin in adults and tadpole&rsquo;s tailfin of a frog Rana cyanophlyctis. MT is generally considered as a potent melanophores aggregating hormone besides regulating the sleep wake cycle in vertebrates. Methods: Melanophore size index (MSI) was chosen as a recording parameter of the responses. Concentr...

In order to overcome the drawbacks of standard shuffled frog leaping algorithm that converges slowly at the last stage and easily falls into local minima, this paper proposed two-phases learning shuffled frog leaping algorithm. The modified algorithm added the elite Gaussian learning strategy in the global information exchange phase, updated frog leaping rule and added the learning capability t...

Calcium channel subtypes in adult rat and frog sensory neuron somata, acutely isolated from dorsal root ganglia (DRG neurons), were studied using Bay K 8644, nimodipine, and omega-conotoxin GVIA (omega-CgTx) as specific probes. The DRG neurons varied in diameter 15-60 microns (rat) and 20-80 microns (frog). Bay K 8644 produced a large increase in calcium currents of small-diameter rat DRG neuro...