搜题请搜索小程序“爱下问搜题”
问题 多项选择题

气象台站迁建以及周围新建、扩建、改建的部门内部建筑物必须同时满足以下要求________。

A．观测场围栏距障碍物最近点的距离与障碍物最高点的比值大于等于10倍

B．从观测场围栏距离障碍物最近点看，障碍物的水平最大遮挡角度小于等于22.5度

C．从观测场围栏距相邻两个障碍物的最近处看，两障碍物无遮挡间距的水平视宽角应大于等于22.5度

D．相邻障碍物之间最近距离应大于30米

答案

参考答案：A,B,C,D

单项选择题

《建设工程质量管理条例》规定，( )必须建立、健全施工质量的检验制度，严格工序管理，作好隐蔽工程的质量检查和记录。

A．监理单位

B．施工单位

C．建设单位

D．勘察单位
查看答案
问答题

(46) It is known that the brain shrinks as the body ages, but the effects on mental ability are different from person to person. Interestingly, in a study of elderly men and women, those who had more education actually had more brain shrinkage.
"That may seem like bad news," said study author Dr. Edward Coffey, a professor of psychiatry and of neurology at Henry Ford Health System in Detroit. (47) However, he explained, the finding suggests that education allows people to withstand more brain tissue loss before their mental functioning begins to break down.
The study, published in the July issue of Neurology, is the first to provide biological evidence to support a concept called the "reserve" hypothesis, according to the researchers. In recent years, investigators have developed the idea that people who are more educated have greater cognitive reserves to draw upon as the brain ages; in essence, they have more brain tissue to spare.
(48) Examining brain scans of 320 healthy men and women aged 66 to 90, researchers found that for each year of education the subjects had, there was greater shrink age of the outer layer of the brain known as the cortex. Yet on tests of cognition and memory, all participants scored in the range indicating normal.
"Everyone has some degree of brain shrinkage," Coffey said. "People lose (on average) 2.5 percent per decade starting in adulthood."
There is, however, a "remarkable range "of shrinkage among people who show no signs of mental decline, Coffey noted. Overall health, he said, accounts for some differences in brain size. Alcohol or drug use, as well as medical conditions such as diabetes and high blood pressure, contribute to brain tissue loss throughout adulthood.
In the absence of such medical conditions, Coffey said, education level helps explain the range of brain shrinkage exhibited among the mentally-fit elderly. The more-educated can withstand greater loss.
(49) Coffey and colleagues gauged shrinkage of the cortex by measuring the cerebrospinal fluid surrounding the brain. The greater the amount of fluid, the greater the cortical shrinkage.
Controlling for the health factors that contribute to brain injury, the researchers found that education was related to the severity of brain shrinkage. For each year of education from first grade on, subjects had an average of 1.77 milliliters 11 more cerebrospinal fluid around the brain.
Just how education might affect brain cells is unknown. (50) In their report, the researchers speculated that in people with more education, certain brain structures deeper than the cortex may stay intact to compensate for cortical shrinkage.
查看答案