药品编码的基本原则有（） A.唯一性 B.合理性 C.可扩充性 D.简单性 E.规范

For many years, people believed that the brain, like the body, rested during sleep. After all, we are rendered unconscious by sleep. Perhaps, it was thought, the brain just needs to stop thinking for a few hours every day. Wrong. During sleep, our brain--the organ that directs us to sleep—is itself extraordinarily active. And much of that activity helps the brain to learn, to remember and to make connections.
It wasn’t so long ago that the regretful joke in research circles was that everyone knew sleep had something to do with memory—except for the people who study sleep and the people who study memory. Then, in 1994, Israeli researchers reported that the average performance for a group of people on a memory test improved when the test was repeated after a break of many hours—during which some subjects slept and others did not. In 2000, a Harvard team demonstrated that this improvement occurred only during sleep.
There are several different types of memory—including declarative (fact-based information), episodic (events from your life) and procedural (how to do something)— and researchers have designed ways to test each of them. In almost every case, whether the test involves remembering pairs of words, tapping numbered keys in a certain order or figuring out the rules in a weather-prediction game, "sleeping on it" after first learning the task improves performance. It’s as if our brains squeeze in some extra practice time while we’re asleep.
This isn’t to say that we can’t form memories when we’re awake. If someone tells you his name, you don’t need to fall asleep to remember it. But sleep will make it more likely that you do. Sleep-deprivation experiments have shown that a tired brain has a difficult time capturing memories of all sorts. Interestingly, sleep deprivation is more likely to cause us to forget information associated with positive emotion than information linked to negative emotion. This could explain, at least in part, why sleep deprivation can trigger depression in some people: memories stained with negative emotions are more likely than positive ones to "stick" in the sleep-deprived brain.
Sleep also seems to be the time when the brain’s two memory systems—the hippocampus (海马体)and the neocortex (新皮质)—"talk" with each other. Experiences that become memories are laid down first in the hippocampus, eliminating whatever is underneath. If a memory is to be retained, it must be shipped from the hippocampus to a place where it will endure—the neocortex, the wrinkled outer layer of the brain where higher thinking takes place. Unlike the hippocampus, the neocortex is a master at weaving the old with the new. And partly because it keeps incoming information at bay, sleep is the best time for the "undistracted" hippocampus to shuttle memories to the neocortex, and for the neocortex to link them to related memories.

How can a piece of information become enduring memory in the brain according to the passage
A. It must go to the hippocampus for processing.
B. It must be transferred to the neocortex.
C. It must eliminate the memory underneath it.
D. It must be captured during the time of sleep.

关于晶体与化学键关系的下列说法中，正确的是(    )

A．离子晶体中一定存在共价键

B．原子晶体中可能存在离子键

C．金属晶体中存在离子，但却不存在离子键

D．分子晶体中一定存在共价键

胶带输送机要增大牵引力，可以（）。

A.驱动滚筒表面润滑

B.增大围包角

探究历史发展的共性是学习历史的任务之一。以下是关于英国、法国、美国三国进行资产阶级革命的共同原因，其中表述准确的是[ ]

A．资本主义经济进一步发展的需要

B．封建专制制度腐朽的结果

C．君权神授与议会矛盾的结果

D．殖民压迫导致民族独立愿望的增强

需求定义包括很多内容，而其中______是业务环境对应用系统施加的某些限制。