The Rules

1. Eligibility

   In order to sign up for a time slot, you must be a member of the Department of Biophysics and Biophysical Chemistry at the Johns Hopkins University School of Medicine. Outside users may use the facility only in collaboration with a member of the department.

2. Communication

   In order to utilize the resources of the lab efficiently, communicate your intention to collect with the facility manager and other users in the queue. After starting your collection, tell the next user and the facility manager when you plan to finish.

3. Duration of time slots

   Flea: 3 days
   Tick: 2 days
   Thor: 1 day

4. Allocation of time

   A time slot (an entry in a queue) is considered an allocation of time for the user's group. The use of the X-ray time by the user is subject to the priorities of the group and can be re-allocated to other members of the group as necessary to satisfy those priorities. This is normally decided by the group leader. If you find that the queue is long and other members of your group have time all ready reserved you could request earlier access to X-ray time from your group leader.

5. Limitations on number of reserved time slots

   A user may be signed up at most twice and may not sign up for an additional slot until data collection from at least one previously allocated slot is complete. That is, a user's name may appear no more than twice amongst all of the queues at any one time. A user's two signups may be in the same queue. If you choose to use a machine for which no one else has signed up, and you already have your name on the lists twice, you must sign up for the "empty" machine and remove your name from one of the other slots.

6. Signing up for time

   To sign up on one of the queues, fill in your user name (usually the same as your computer log in name) beside the list for the detector that you wish to use. It is not necessary to enter your real name or group name unless something different than the database info is desired. Otherwise, these fields will be filled in automatically. (Please, let me know if there is an error in the database).
   • Indicate in the Comments box any special requirements such as the amount of notice required to prepare samples (assume that 2 weeks is standard notice), cooling not required, any special dates you need it for ...

7. Removing a signup

   To remove yourself from the queue or if you wish to swap places with someone else, see the facility manager or send an e-mail. Please also send e-mail also to the next two people in the queue in order that everyone has adequate warning of a possible change of schedule.

8. Bumping

   Bumping is now automated in the queue system, and the following historical notes are provided for understanding the premise of the bumping algorithm. In order to prevent one group from getting too much contiguous time at once on any given queue, bumping (signing up in the middle of the list, not at the end) by a user of one group is allowed (and even encouraged) between two users (not necessarily sequential) of a different group, provided that 10 days notice is given to those whom you bump. Therefore you cannot bump the person who is second in line, but you could bump the third person in line, if their projected starting time is more than 10 days from "now" and somebody else from that group is currently collecting. To bump, be sure to enter the correct number in the box provided. For example you work for Dan Leahy and the list looks like:

   				# User      Group
   				1 bianchet  amzel
   				2 libby     wolberger
   				3 graeme    lattman
   				4 sandra    amzel
   				5 apo       lattman
   		

   You could bump the #4 or #5 positions, since either is more than 10 days from now and since someone else from the amzel and lattman groups is ahead of those positions in the list. If you are bumping with only about 10 days notice, it would be considerate of you to talk with the person you are bumping, just in case they really need at least 10-days advance notice to set up, for example, heavy-atom soaks.

9. Crystal testing

   Short beam time (a few hours) for testing crystals is available between each assigned slot on each detector. If you need time to check crystals, fill in the form for Crystal testing. Unless otherwise specified, it should be assumed that you will use whichever system is available first (or at the time you specify).

10. Finishing up

    When you have finished or when you think you know when you will be finished, please notify the next person on the list and me by e-mail and any people who wish to test crystals before the next person in the queue gets started.

11. Cleaning up

    Please clean up the work area on the surface of the generator that you were working at and also around the workstations in the X-ray lab. I will have to start throwing out any junk I find left behind, valuable or not!

12. Cleaning up the disks

    Old data files are purged when the data disks approach full capacity. Please be aware of this, so that it will not take you by surprise to find that your data has been deleted. A warning email is sent out before a purge run, but it is the user's responsibility to be sure that their data are backed up to their own satisfaction prior to the time the email is sent. In the X-ray lab, copies of the data are available in our data archive computer as well.