Pаssаge B Trаumatic brain injuries are assоciated with cоgnitive decline later in life, and a sharper drоp in cognition as we age, a study of twins who served in World War II shows.There is robust research demonstrating a relationship between head injuries and cognitive impairment or dementia later in life, “but I do not know of any others that use a twin-study design,” said Holly Elser, an epidemiologist and resident physician in neurology at the University of Pennsylvania who peer-reviewed the study.The study published in Neurology on Wednesday found that individuals who had a traumatic brain injury were more likely to have lower scores on cognitive tests when they were about 70 years old.They were also more likely to have rapidly declining scores after their first test if they had multiple traumatic brain injuries, lost consciousness because of a head injury or were 25 or older when the injury happened.“Even if it’s just a single traumatic brain injury, we now know that it led to worse cognitive outcomes later in life,” said Marianne Chanti-Ketterl, the lead author of the study and an assistant professor in psychiatry and behavioral sciences at the Duke University School of Medicine.The study of identical and fraternal twins allows researchers to compare participants to each other while controlling for some, if not all, of the underlying genetic factors and some of the twins’ early life conditions. Identical twins share 100 percent of their genes, while fraternal twins share about half. The dominant genre of the above passage is
Pаssаge A When Senаtоr Chuck Grassley first gоt intо politics, Ike Eisenhower was president of the United States. It was 1959, the same year the first transcontinental commercial flight made it from Los Angeles to New York’s Idlewild Airport, later to be renamed in honor of John F. Kennedy. Late in the year, IBM introduced the 7090, a milestone computer model that relied on “transistors, not vacuum tubes.” Grassley served in the Iowa House, then served three terms in the U. S. House. He’s now in his seventh term in the Senate. And he announced last September, a week after his 88th birthday, that he’s running again. That will make him 95 years old at the end of his next term. Simply put, this is too damn old to be doing this job. It’s too old to be doing just about any job. The FAA mandates that pilots retire at 65. Their colleagues in air-traffic control are out at 56, though they can get exceptions to work until they’re 61. Most police departments show employees the door in their 60s. At white-shoe law firms, partners are often pointed to the exit sign by age 68. Foreign-service employees at the State Department are out at 65. Mandatory retirements are mostly verboten in the United States. But there are some professions with such intense physical and mental demands, that require such high-stakes decision-making and mental acuity, that we’ve decided they’re just different. The overall genre of this passage is