the internal structure of dna-ctab and dna-ddab is investigated by a small angel x- ray scattering(saxs) instrument. hexagonal packing of dna was observed for dna complex with ctab, and for ddabcomplex is observed lamellar structure. variations in the internal spacing and degree of long-range ordering aredependent on both surfactant type and concentrations of added salt. when we increased the a...

introduction: clinical application of radiography in endodontic practice is affected by reproducibility in the orientation of the x-ray source, image receptor and object. the inability of dentists to locate intra oral films or sensors in appropriate positions in different cases can cause complications in the performance of endodontic therapy. commercially available film holder (endoray) and con...

geomagnetic field is a one of the candidates for creation of anisotropy in azimuth distribution of extensive air showers over the entered cosmic rays to the atmosphere. here we present the question: is there any azimuth anisotropy flux in the upper level of the atmosphere due to the geomagnetic field over the entered cosmic-rays? the obtained answer is: yes. this investigation showed an agreeme...

background and objective: chest x-ray is usually the first radiography performed for a newborn. this test is easily accessible and yet a basic screening method. different results have been reported in various studies regarding the diagnostic value of chest x-ray in cardiovascular disease in children. materials and methods: the study was carried out retrospectively using the medical files of 100...

Cosmic Rays (CR) travel at speeds essentially indistinguishable from the speed of light. However whilst travelling through magnetic fields, both regular and turbulent, they are delayed behind the light since they are usually charged particles and their paths are not linear. Those delays can be so long that they are an impediment to correctly identifying sources which may be variable in time. Fu...

clay minerals are considered the most important components of clastic reservoir rock evaluation studies. the shurijeh gas reservoir formation, represented by shaly sandstones of the late jurassic-early cretaceous age, is the main reservoir rock in the eastern kopet-dagh sedimentary basin, ne iran. in this study, x-ray diffraction (xrd), x-ray fluorescence (xrf), scanning electron microscopic (s...

repeating x-ray radiographs, as a common problem in radiology units, represent additional, non-billable costs due to increased film, chemistry, and equipment use as well as increased personnel time. furthermore, patients receive additional radiation exposure from repetitions and must remain on the premises until the second exam is completed. compounding the overt negative financial impact on th...