Preserving a Text Window
There is a subtle feature of ACeDB that may confuse you if you are not aware of it. In general, ACeDB prefers to reuse a window rather than create a new one. This feature is intended to help preserve a valuable resource - memory - which at times may be in short supply.
The general rule is implemented as follows. If a window containing a certain kind of information is already being displayed - say, the characteristics of a restriction enzyme - then bringing up information on a second restriction enzyme will result in the new information overwriting what was in the original window. If the intention was to compare the two enzymes, this is obviously not helpful.
There is a simple way to prevent window reuse, and it is shown in the accompanying figure. The Main KeySet now contains the names of all the restriction enzymes in the database. (The user first double-clicked on the Motif class in the AAtDB main window). The user has brought up a window displaying information about AfaI by double-clicking on AfaI in the Main KeySet. To preserve this window, the user then clicked once (using the leftmost mouse button) on the word Site in the AfaI window, which highlighted it. The user then went back to the Main KeySet and double-clicked on AlwI. ACeDB created a new window, rather than overwriting the AfaI window.
Clicking once on any item in a text window has the potential to preserve it. Thus, in our example, clicking on any item in the AfaI window would have served the same purpose: GTAC, Offset, or Takara, among others.
Text Window Anatomy
Before we leave this example, we want to emphasize an important point about text windows and the information they contain. Compare the AfaI and AlwI windows and notice the differences between what is known about these two Restriction class members. For example, the AlwI window contains a Remark, while the AfaI window contains a Paper and a short list of Isoschizomers.
Text windows vary greatly in their complexity and layout, depending not only on the class from which their information is drawn, but also on how much information is available on a given item. Classes in ACeDB have a large variety of "slots" in which different kinds of information can be stored: for example, Paper is a slot in the Motif class. Most often though, only a subset of slots have actually been filled for a particular class member (there is no paper associated with AlwI). Unlike some databases, ACeDB does not show the names of empty slots on screen. Instead, the blank slots are not shown so that the window can be as compact as possible.
Text Windows Have Menus We have used the rightmost mouse button to pull down the menu for the AlwI window. A text window menu has Quit and Help options. Notice also the items Print and Text dump. These provide two ways to copy information out of AAtDB, for example, to make a figure or to place the information into a word processing document.
AAtDB will print the information or picture in a window to a PostScript printer if the Print pop-up menu item is chosen. Check with the system manager to determine which printer is set up for use by the ACeDB database in use at your site.