The epibranchial placodes generate the neurons of the geniculate, petrosal, and nodose cranial sensory ganglia. Previously, it has been shown that bone morphogenetic proteins (BMPs) are involved in the formation of these structures. However, it has been unclear as to whether BMP signalling has an ongoing function in directing the later development of the epibranchial placodes, and how this sign...

The colony defense behavior of the wasp Mischocyttarus cerberus Richards (Hymenoptera, Vespidae) was studied to verify whether there were different reactions of wasps of different ages and hierarchical positions during attacks of ants. Detailed nest mapping was first performed, then the wasps were marked and were divided in four distinct categories: queens, older workers, younger workers and ma...

In Xenopus, mesoderm induction by endoderm at the blastula stage is well documented, but the molecular nature of the endogenous inductive signals remains unknown. The carboxy-terminal fragment of Cerberus, designated Cer-S, provides a specific secreted antagonist of mesoderm-inducing Xenopus Nodal-Related (Xnr) factors. Cer-S does not inhibit signalling by other mesoderm inducers such as Activi...

A new species of Harmonicon F. O. Pickard-Cambridge, 1896 (Araneae, Dipluridae) is described, from a medium-sized lateritic cave in Parauapebas, Pará, Brazil. The male holotype and only specimen known of H. cerberus sp. n. was found near the entrance of Pequiá cave. This taxon is the fourth species described and the southernmost record for the genus. The new species displays some troglomorphic ...

Horizontal Permeability kh m 1.5×10 [10] 9×10 [10] 10 [1] Specific Storage SS m 5×10 [8] 2.7×10 [9] 10 [1] Aquifer Head h@t=0 m 0 [6] 130 [6] 5×10 [18] Aquifer Depth D m 55 [7] 2000 [6] 5×10 [1] Aquifer Thickness H m 16 [5] 3×10 [6] 5×10 [18] Kinematic Viscosity ν m/s 0.658×10 [2] 1.78×10 [2] 1.5×10 [18] Fissure Width w m N/A N/A 2.0 [1] Manning’s Number n None 0.012 [2] 0.05 [2] 0.04 [15] PARA...

The formation of the head is a multistep process beginning early in embryogenesis. Transplantation, gene knock-out and gene-transfer experiments indicate the existence of a head organizer as a separate entity, which is distinct from the trunk organizer (for reviews see Bouwmeester and Leyns, 1997; Harland and Gerhart, 1997). A common vertebrate characteristic is the successive appearance and th...

BACKGROUND Signals from anterior endodermal cells that express the homeobox gene Hex initiate development of the most rostral tissues of the mouse embryo. The dorsal/anterior endoderm of the Xenopus gastrula, which expresses Hex and the putative head-inducing gene cerberus, is proposed to be equivalent to the mouse anterior endoderm. Here, we report the origin and signalling properties of this ...

BACKGROUND In vitro simulation of developmental processes is an invaluable tool to shed light on the intrinsic mechanism of developmental biosystems such as central nervous system in mammals. Chick somites have been used to simulate the neural differentiation of human neural progenitor cells. In the present study, we aimed to indicate whether somites have the ability to express required neural ...