background: treatment of chronic constipation is creating one of the major problems for doctors and patients. pyridostigmine increases the gastrointestinal motility through the effects on cholinesterase. it seems that this mechanism can reduce chronic constipation. the aim of this study was to compare the effects of pyridostigmine and bisacodyl on chronic constipation. methods: this study was c...

The diagram showing off-center nested spheres which is traditionally used to illustrate the Doppler effect, misleading and its trigonometric analysis leads errors concerning light, because electromagnetic aberration effects conform a wavefront surface that not sphere but an ellipsoid stretched along trajectory of source. Cartesian polar equations spherical ellipsoidal wavefronts are compared he...