Opuntia pinkavae Opuntia pinkavae Opuntia pinkavae, common names Bulrush Canyon prickly-pear or Pinkava's pricklypear, is a species of cactus known only from northern Arizona and southern Utah. It grows in sunny locations in grasslands, on the edges of pinyon-juniper woodlands, on sandy or limestone soils. It was named for Dr. Donald Pinkava, professor emeritus at Arizona State University in Tempe. He studied "Opuntia" for many years. The species is one of the smaller members of the group, rarely more than 25 cm (10 inches) tall. Stems are green, flattened, up to 15 cm (6 inches) long. Flowers are magenta with yellow to
Standard person patients to radiation. According to the International Commission on Radiological Protection's 1974 definition, “Reference man is defined as being between 20-30 years of age, weighing 70 kg, is 170 cm in height, and lives in a climate with an average temperature of from 10°C to 20°C. He is a Caucasian and is a Western European or North American in habitat and custom.” Standard person The standard person or reference person is a theoretical individual that has perfectly "normal" characteristics. This model is used for much research into radiation safety. For many years, the standard person was called reference man because