Most babies are able to begin sitting up when they reach the age of 4 months. However, some of them might need more time and start sitting independently when they become 7 months old. Until this time, the baby would definitely have learned how to roll and would be able to hold his head up too.
UV radiation, in the form of lasers, lamps, or a combination of these devices and topical medications that increase UV sensitivity, are sometimes used to treat patients with certain diseases who have not responded to other methods of therapy.
How are gamma rays used? Gamma rays are a form of electromagnetic radiation, and they have the greatest energy of all forms of electromagnetic radiation. Gamma rays can easily penetrate most materials, including lead. Gamma rays are classified as ionizing radiation and are therefore hazardous to living cells.