Satellite cells are quiescent muscle stem cells that promote postnatal muscle growth and repair. Here we show that myostatin, a TGF-beta member, signals satellite cell quiescence and also negatively regulates satellite cell self-renewal. BrdU labeling in vivo revealed that, among the Myostatin-deficient satellite cells, higher numbers of satellite cells are activated as compared with wild type....

Skeletal muscle has great regenerative capacity which is dependent on muscle stem cells, also known as satellite cells. A loss of satellite cells and/or their function impairs skeletal muscle regeneration and leads to a loss of skeletal muscle power; therefore, the molecular mechanisms for maintaining satellite cells in a quiescent and undifferentiated state are of great interest in skeletal mu...

invention of satellite and the use of it in the broadcasting technology ,evolved the broadcasting organizations activities. on one hand, it developed the scope of broadcasting geographically and to some extent solved the limitations and problems of transmitting signals such as difficulties in receiving the signals in mountainous or wood areas. on the other hand, the use of satellites on transmi...

A long time ago, since the launch of the first artificial satellite in 1957, controling attitude of satellites has been considered by the designers and engineers of aerospace industry. Considering the importance of this issue various methods of control in response to this need have been presented and analyzed until now. In this paper, we propose and analyze a three-axis optimal control on the s...

Automatic identification and localization of cartographic objects in aerial and satellite images have gained increasing attention in recent years in digital photogrammetry and remote sensing. Although the automatic extraction of man made objects in essence is still an unresolved issue, the man made objects can be extracted from aerial photos and satellite images. Recently, the high-resolution s...

Compared with Geostationary Orbit (GEO) satellite systems and Medium Earth Orbit (MEO) satellite systems, Low Earth Orbit (LEO) satellite systems provide lower propagation delay as well as higher throughput. Because of these reasons, LEO satellite systems can play a pivotal role in providing services to areas where there is no substantial terrestrial infrastructure. In this paper, a novel kind ...

a considerable part of precipitation falls in the form of snow in golestan watershed. in turn, snowmelt plays a significant role in surface runoff, groundwater feeding and flood propagation in this area. snow cover area (sca) as an indicator of stored water can be implemented for temporal and spatial monitoring of snowmelt in the hydrological models. to monitor spatial and temporal variation of...

The genus Rattus has two related families of satellite DNA: Satellite I consists of tandem arrays of a 370 base pair repeat unit which is a dimer of two 185 base pair portions (a, b) which are about 60% homologous. Satellite I' consists of tandem arrays of a 185 base pair repeat unit (a') which is about 85% homologous to a and 60% homologous to b. R. norvegicus contains only satellite I but R. ...

Small satellite technology has opened a new era in aerospace engineering by decreasing space mission costs, without greatly reducing the performance. The concept of formation flying using small satellites is becoming popular because of their potential to perform coordinated measurements of remote sensing space missions. The current state of art in satellite communications is a one hop link betw...