abstract   background: the x-ray machines used for radiodiagnosis should meet certain quality assurance (qa) programmes . these are necessary to have good quality radiographs at reasonably low exposure to patients.   materials and methods: dose reduction methods in abdomen x-ray examination were carried out in 10 hospitals in tehran. this paper presents the work, which was implemented on 200 pa...

The room temperature X-ray responses as functions of time of two n type cubic GaN Schottky diodes (200 μm and 400 μm diameters) are reported. The current densities as functions of time for both diodes showed fast turn-on transients and increases in current density when illuminated with X-ray photons of energy up to 35 keV. The diodes were also electrically characterized: capacitance, implied de...

Two studies examined effects of ambient darkness and chronic beliefs about danger on activation of stereotypes about Blacks. Chronic beliefs were measured by a Belief in a Dangerous World (BDW) questionnaire. In Study, 1, participants in either a dimly lit or dark room saw photos of Black men and rated the extent to which specific traits described the cultural stereotype of Blacks. In Study 2, ...

An aging woman kneels next to a grave that has been dug in the dirt along the wall of a one-room cell. This is the cell she has been confined to for life, a tiny room off the main chapel of the village church. The grave yawns wide, dark and foreboding, in the corner of her little room. The tips of her fingernails are still black, filled with the dark earth of the grave they have moved for the d...

mazafati date is a wet and semi-dried date fruit type with dark red to black color that has premier quality. because of its high moisture content, date fruits of this variety are very perishable at room temperature and therefore must be refrigerated during storage. in this study, effect of air temperature (50, 60, 70, 80 and 90 ˚c) and air flow rate (1, 1.5 and 2 m/s) in hot air drying of mazaf...

The pomegranate (Punica granatum L.) is an important medicinal plant. It has been reported that phenolic compounds contained in the flowers have antioxidant potential. The objective was to determine the concentration of total phenolics and antioxidant capacity of three selections of pomegranate flower dried under different conditions. The highest phenolic content and antioxidant capacity was ob...

Richard was fifteen years old and had obtained his working papers but he could not keep a job. He had trouble with his employers, and bore grudges toward his fellow employees. He was insubordinate, refusing to carry out instructions because of his unreasonable fear of the dark where skeletons and ghosts flit. He could not serve his apprenticeship as a shoe clerk satisfactorily because the stock...

The distribution of the stellar and gaseous components in low surface brightness galaxies has been determined directly from optical and HI imaging. The distribution of what might be the dominant mass component, the dark matter, which is inferred from rotation curves, is far harder to determine. Although the rotation curves themselves can be determined fairly accurately from HI synthesis observa...