Iris sphincter muscle Iris sphincter muscle The iris sphincter muscle (pupillary sphincter, pupillary constrictor, circular muscle of iris, circular fibers) is a muscle in the part of the eye called the iris. It encircles the pupil of the iris, appropriate to its function as a constrictor of the pupil. It is found in vertebrates and some cephalopods. Initially, all the myocytes are of the smooth muscle type but, later in life, most cells are of the striated muscle type. Its dimensions are about 0.75 mm wide by 0.15 mm thick. In humans, it functions to constrict the pupil in bright light (pupillary light
In the Light of What We Know In the Light of What We Know In the Light of What We Know is the debut novel of Zia Haider Rahman. First published by Farrar, Straus and Giroux, the novel was released in the spring of 2014 to international critical acclaim and earned its author the James Tait Black Memorial Prize, Britain's oldest literary prize. and the inaugural International Ranald McDonald prize 2016. The novel has already been translated into Dutch, French and Portuguese and is to be translated into several other languages. Much of the novel is set during the war in Afghanistan at the beginning of the