Evolution of morphogenesis is generally associated with changes in genetic regulation. Here, we report evidence indicating that dorsal closure, a conserved morphogenetic process in dipterans, evolved as the consequence of rearrangements in epithelial organization rather than signaling regulation. In Drosophila melanogaster, dorsal closure consists of a two-tissue system where the contraction of...

A highly coherent 523.92± 0.05 Hz periodic X-ray signal has been observed during a type I X-ray burst from the low-mass X-ray binary system KS 1731-260 with the PCA on RXTE. The spectral evolution of the burst indicates photospheric-radius expansion and contraction. The 524 Hz signal occurred at the end of the contraction phase, lasted for ∼2 s, was highly coherent (Q ∼> 900), and had a pulse f...

We propose a new method for computing the ground state properties and the time evolution of infinite chains based on a transverse contraction of the tensor network. The method does not require finite size extrapolation and avoids explicit truncation of the bond dimension along the evolution. By folding the network in the time direction prior to contraction, time-dependent expectation values and...

human language, over its evolutionary history, has emerged as one of the fundamental defining characteristic of the modern man. however, this milestone evolutionary process through natural selection has not left any ’linguistic fossils’ that may enable us to trace back the actual course of development of language and its establishment in human societies. lacking analytical tools to fathom the cr...

Abstract Background Paphiopedilum is the largest genus of slipper orchids. Previous studies showed that phylogenetic relationships this are not well resolved, and sparse taxon sampling documented inverted repeat ( IR) expansion small single copy (SSC) contraction chloroplast genomes . Results Here, we sequenced, assembled, annotated 77 plastomes species (size range 152,130 – 164,092 bp). The ph...

as fetal compensation against hypoxemia progresses, the afterload on the heart and peripheral vascular resistance increases. eventually, the right heart fails, which is transmitted to the fetal venous system, causing decreased flow during late diastole or atrial contraction and increased resistance in the ductus venosus and inferior vena cava. the ductus has forward flow during atrial contracti...

The troponin complex, composed of Troponin-I, Troponin-T and Troponin-C, is an essential mediator of the contraction of striated muscle downstream of calcium signaling in almost all bilaterians. However, in echinoderms and hemichordates, collectively termed Ambulacraria, the components of the troponin complex have never been isolated, thus suggesting that these organisms lost the troponin syste...