The Sharp Electronic Organizer--A Warning

tein chain, the alpha-carbon backbone with disulfides and tri-NAG. all main-chain atoms and hvdroeen bonds. and all amino-acid side chains in separate...
0 downloads 0 Views 2MB Size
the computer bulletin board tein chain, the alpha-carbon backbone with disulfides and tri-NAG. all main-chain atoms and hvdroeen bonds. and all amino-acid side chains in separate sets-for instance, the set of all alanines. or the set of all ~lutamines-thatcan be turned on and off separately in M ~ ~ . (3) A tour of MAGE, in which students studv structure and bonding in the l y s & y m e / t r i - ~complex.-A6 ~~ the students work through the tutorial, they discover many structural details for themselves. For instance, they are required to find all hydrogen bonds between tri-NAG and &ozyrne main-chain or side-chain atoms. In doing so, they learn how to apply chemical, distance, and geometric criteria to recoenize noncovalent interactions in a comnuter model. The-tutorial directs students to employ the kajority of MAGE tools: display buttons, to turn specific parts of models on and off;rotating, centering, and zooming; z-slabbing, to control the display of background and foreground atoms; viewing in stereo and learning the important skill of using stereo without a viewer; labeling atoms and displaying their coordinates; measuring distances, bond angles. and dihedral aneles. to discover hvdroeen bonds and " other interactions; drawkg lines to represent bonds not shown a u t ~ m a t i c a l lsuch ~ as motein-lieand bonds: runing, to eliminate unwanted atoms fromyhe display; Ereating useful vicws and addine them to the displav . . menu: and sanng modified kinemage;. To complete the tutorial and reinforce newly acquired skills, I assign each student another small protein to study, using what they learned from the tutorial about how to explore a protein using PREKIN and MAGE. Then I ask them to write a report on the protein, illustrated with kinemages. They model their report after introductions to specific proteins in their biochemistry text. This follow-up assienment has the added advantaee of satisfvine our de" partment's requirement that all upper-division lab courses include at least one maior writine a s s i m e n t . in addition to routine lab reports.

-

-

-

-

-

-

Several other introductions to MAGE are available. The Internet MAGE package (5) includes t h e file Demo3Xxa.kin, which introduces some of MAGE's display possibilities. In my tutorial, this file gives the students their first taste of MAGE functions. The Internet package also includes the file Cookbook.kin, a very brief introduction to PREKIN. A MAGE-based ancillary to Moran and Scrimgeour:Biochemistry (6, 7)contains the file Intmkin, which introduces the basics of viewing prepared files in MAGE. Finally, the kinemage supplement to Branden and Tooze: Introduction to Protein Structure (8,9) contains the file clBasic.kin, which introduces a few MAGE functions and ~rovidesan excellent interactive studv of ~ o l v o e ~ t i d e conf&mation. While all of these introduc&ons are useful and of hieh aualitv. none of them eive beeinnine students everything tiey need to become i;depenient explorers of macromolecular structure. includine an introduction to PDB files, hands-on experiknce a variety of disd a v files with PREKIN. and ex~lorationwith MAGE that eon%ncingly shows the'power of graphics for discovering details of molecular structure.

. .. .

How to Obtain the Tutorial

To obtain this tutorial with full instructions for teachers, set your W W W browser to gopher://gopher.usmacs.maine.edu:70/lle%3A/usm/chem and download the file MAGE.RTF. Tu use Gopher instead, set a Gopher Journal of Chemical Education

Acknowledgment

Thanks to the students in the Fall 1994 section of my biochemistry laboratory for helping me to test and improve the tutorial. Macromolecular scientists and teachers everywhere should be grateful to Jane and David Richardson and to the management of The Protein Society, publishers of Protein Science, for free access to the excellent programs MAGE and PREKIN. Their efforts make it feasible to bring to every desk and classroom the vast resources of the Protein Data Bank. I can recall no greater single step forward for the teachine of macromolecular science. Editor's Note: versions of MAGE and PREKIN for PC comvuters running Windows V3.1 or ereater are contained in the self-expanding file MAGE.EX~obtainable as indicated in (5). Llterature Cited 1. Richardson,D. C.; Richardson,J. S. Rot. Sci. lm.1, a. 2. Richardson.D. C.: Richardson.J. S. &nda in Biahem S d 1984.19.13~138 3. Bemstein, b C.; E&tZle, T. F-wlliams, G. J. B.; Meyer, Jr,E. I?; Brice, J. R.;Rods. em.R.:Kennard. 0.:Shimsoouchi. T:T u s a m i M J . Mal. Bid. 1977.112.635542.

. .

6. Cheetham,J. C.;Artymiuk,PJ.;F'hiUipa.D.C. J. Mol. Bid 1998,224,613, 6. Moran, L. A ; Scz5mgrimsur.K G. Biahemisfry; Neil Psttermn: Englewod Cliffi, NJ, 1991. -~ I. Morao, L. A ; Scrimgwur, K G. Exploring M o k u l a r S m r c ~ r (lrinlrinage . supplement);Neil Patteram: Englewad Cliffa, NJ, 1994. 8. Blanden, C.; Iboze, J. Intmdudnn t o h t e i n Strudum; Garland: New York,1991. 9. Richardson, D. C.; Richardson, J. S. The Kimmzga Svpplemonf to Intmdution to Pmhin Struturn: Garland: New Y e 1991. ~

~

The Sharp Electronic Organizer-A Warning

Other lntroductlonsto MAGE

A180

link to gopher.usmacs.maine.edu and open, in succession, the folders Campus Information by Department and CHEM. Then open the file MAGE.RTF and save it. Import the file with ClarisWorks (for best results) or other word processors. Send a message t o t h e a u t h o r a t rhodes~sm.maine.eduifyourunintotroub1e.

Thomas A. Eaton

Division of Science and Mathematics St. Thomas University 16400 N.W. 32nd Ave. Miami, FL 33054 The Sharp Electronic Organizer, Model YO-llO,34KB is a must for all scientists, engineers, and professionals. It has a calendar to remind you of birthdays, holidays, anniversaries, appointments, meetings, etc., and a schedule to help organize your day. There is a memo section to store jokes, quotations, equations, or whatever using the alphanumeric keypad. And with 34kB of memory, about half that of a Commodore, TRS 80 or Apple 11, it fits neatly into your pocket, the size of a pocket calculator. It has a port to interface with instruments, printers, or other microcomputers. No, this isnVta paid testimonial, although I'd be glad to write one in exchange for an electronic organizer and interfaces to my instruments and microcomputers. This is a warning to other chemistry professors to check your students' pocket calculators. I found this electronic marvel durine an exam in mv eenera1 chemistry class last week. ~ct&lly,I'd been &-the lookout for such devices for the vast w u ~ l eof vears. when students began to use the tbree-iich screen grapihia &leulators.They made me uncomfortable because one of mv tvDical organic chemistry exam questions is to draw a p~tentiaien-

the computer bulletin board ergy diagram showing energy as a function of dihedral angle for rotation about a single bond in a substituted alkane. I would prefer that the student work this out during the exam and not come in with it stored in memory in a pocket calculator. One of the students in my general chemistry class had one of these calculators, so I inspected all of the pocket calculators, exchanging my Casio Scientific Calculators, model fx-300A for any objectionable calculator. I was impressed by the capabilities of the Sharp Electronic Organizer. I peered through the memo section, findingnotes1ike"Doyou want to have sex? No not now." and the like. I felt r e d y guilty, as though I were reading someone else's mail, and was about to return it to the student when I noticed the word "secret" in blue, the second function key color code. When I pressed second functionlsecret the Electronic Organizer responded with "Allow Access of Secret Data," and a space for a seven character user authorization code. I tried "A," "1,"and "Cheml," with the same result each time: "Inwrrect Password!' I don't know if the student was trying to cheat on the exam, or not; I never got into the secret memory. I hope he had more information in the "secret" memory than he had in his brain; he failed the exam miserably. There were a few possibilities for user wdes that I thought of after the exam, like CHEM101, or the student's name, but they occurred to me too late. I know one thing for sure: 34 kilobytes is enough to store the entire text, all of its problems and answers, and class notes, as well. This would be fine on an open-book, open note exam with objective questions, but is clearly inappropriate on a multiple choice exam - unless each student has the same computational power. This is especially true at a school where a test bank or study guide is available (or potentially available) to the students. For example, I once graded physical chemistry homework at the University of Pittsburgh, and found answers plagiarized from Atkins'study guide. It was unavailable to the students at PIl"l,' but perhaps available a t the Carnegie-Mellon University bookstore, across the street! Clearly the Sharp Electronic Organizer is a powerful tool - a must for the professional!

A182

Journal of Chemical Education

Management of First-Year chemistry ~ ~Using Spreadsheets Frank E. Collins and Charles W. Williams

Department of Chemistly and Physics, Louisiana State University in Shreveport One University Place. Shreveport, LA 71115-2399 The Problem

In the manaeement of our firstyear chemistry laboratory we are forced to use undergraduate lab assistants who, though diligent workers, lack experience and knowledge in evaluating lab reports submitted by students. In the past the Department has dealt with this problem by allowing the students to enter their names and experimental data into very old IBM 3278-2 computer terminals wired to an IBM ES9000 mainframe; from it we later retrieved a spreadsheet showing the computational results, sorted according to increasing percentage error of each result or the alphabetical order of student names. Assistants then used the information as an aid in grading lab reports. We found the process to be cumbersome, slow, and unreliable; in a word-unacceptable. The Solution

We borrowed two Zenith notebook computers that were old but capable of loading Microsoft Excel 2.1. Spreadsheets were developed as needed for each experiment. Students entered their data directly into the computers and on a hard copy for backup. The spreadsheets were protected to prevent deletions and other changes. The information was saved to disks, then later combined to make one spreadsheet using Microsoft Excel 5.0 on a PC from which computational results were made, analyzed, and given to the lab assistants. Some of the information available to assistants were mll call data computational results statistical evaluation of results "fishy"data (plagiarism) grade assignment sorting selections of one's choice The Outcome

Interest of the students was raised to a higher level, probably due in part to the introduction of more so-

b

~

~