Atmospheric dispersion produces spectral elongation in images formed by land-based astronomical telescopes, and this increases as the telescope points away from zenith. Dispersion Correctors (ADCs) produce compensating that can be adjusted to best cancel out atmospheric effect. These correctors are generally of two basic types: Rotating (R-ADCs), Linear (L-ADCs). Lately, a third type, “Compensa...

In this study, isovolumic bronchial segments and bronchial rings were used to investigate the influence of airway diameter on smooth muscle force generation and acetylcholine responsiveness. Segments with internal diameters ranging from 1.0-6.0 mm were obtained from the mainstem bronchus of eight pigs. Responses to increasing acetylcholine concentrations were quantified in segments by intralume...

Waterwheels are the oldest types of hydraulic machines. These turbines are of relatively simple design, large diameter, low rotational speed and high torques. But applying them as micro hydros of high speed and small diameter is yet to be explored. A micro hydro waterwheel of one meter diameter was designed and manufactured at the Iranian  esearc†h Organization for Science and Technology (IROST...

The size, especially the root size, of advance oak (Quercus spp.) reproduction provides the best indication of the growth potential afer release or top-kill. This study examined the relationship between the size of the root system and various diameterheight measurements for small (<60 cm) white oak (Q. alba L.) seedlings. Diameters measured at the top of the litter and humus luyers and at the r...

The flow about, and drag of, two types of parachute canopy have been examined at supersonic speeds at zero incidence, in isolation and in the presence of rigging lines,and behind bodies of revolution. The investigation has shown that the presence of rigging lines reduces the canopy drag by an extent dependent upon the length of the lines. Several different flom regimes are encountered similar t...

We numerically investigated margination of leukocytes at arteriole shear rate in straight circular channels with diameters ranging from 10 to 22 μm. Our results demonstrated that passing motion of RBCs effectively induces leukocyte margination not only in small channels but also in large channels. A longer time is needed for margination to occur in a larger channel, but once a leukocyte has mar...

Lianas (woody vines) reduce growth and survival of host trees in both temperate and tropical forests; however, the relative strength of liana-tree competition in comparison to tree-tree competition remains unexplored. When controlling for biomass, lianas may have greater competitive effects than trees because the unique morphology of lianas allows them to reach the forest canopy at relatively s...

rehabilitation of arid and semi-arid regions by tolerant native plant cover is a primary concern to create a sustainable balanced ecosystem. thus, the existing plant species of the region should be recognized together with a comprehensive survey and study of the environmental factors such as climate and soil conditions which affect the establishment of these plant species. this paper attempts t...

How small can the diameter be made by adding a matching to an n-cycle? In this paper this question is answered by showing that the graph consisting of an n-cycle and a random matching has diameter about log2n, which is very close to the best possible value. It is also shown that by adding a random matching to graphs with certain expanding properties such as expanders or Ramanujan graphs, the re...