Life on Earth can be traced back to as far as 3.8 billion years (Ga) ago. The catastrophic meteoritic bombardment ended between 4.2 and 3.9 Ga ago. Therefore, if life emerged, and we know it did, it must have emerged from nothingness in less than 400 million years. The most recent scenarios of Earth accretion predict some very unstable physico-chemical conditions at the surface of Earth, which,...

A satellite, in its orbit, is affected by perturbing forces, such as atmospheric drag, solar radiation pressure, Earth oblateness, and gravity of the celestial masses (other than the Earth). In this paper, the effects of these forces on the trajectories of different types of LEO satellites and a sample satellite (Z-SAT) are discussed. A few analyses are done on these orbits and the relevant res...

Background: Control and maintenance of endotracheal tube cuff pressure and prevention of sore throat are major concerns in post-anesthesia care. Aim: This study aimed to evaluate changes in the pressure of the endotracheal tube cuff filled with saline versus air and post-anesthesia sore throat when the position is altered from supine to lateral. <st...

A systematic examination of the braces commonly used in Europe lacks in literature. Therefore the objective of this report is the description of the European braces widely used. The history, design rationale, indications, biomechanics, outcomes and comparison between some braces are reported. Chêneau Brace is used in France and other European Countries. There are two Cheneau derivatives, namely...

[Purpose] The purpose of this study was to examine the pressure-relieving effects of a continuous lateral turning device on common pressure ulcer sites. [Subjects] Twenty-four healthy adults participated. [Methods] The design of our continuous lateral turning device was motivated by the need for an adequate pressure-relieving device for immobile and/or elderly people. The procedure of manual re...

the khorasan region is one of the active seismic zones in iranian plateau, which is located between central iran and kopet-dagh zones. we study the crustal thickness (h) and vp/vs ratio (k) in mashhad, capital of razavi khorasan province by the receiver function method. this study uses teleseismic events recorded by an array of three broadband stations of khorasan seismic network, earthquake re...