Prlnclples ofChemistry J & S Software. 135 Haven Avenue, Port Washington. NY 11050 Hardware: Apple II Family Components: Two disks and Manual Level and Subject: High School and Junior College. Princioies of Chemistrv Cost: $170
Summary Ratlngs: Category Ease 01 Use: sublect mner Content: Pedagogic Value: Student Reaction:
Ex~~llent God Average God
Revlew Principles of Chemistry is a series of lessons designed to cover four of the main topics covered hy high school or junior college chemistrv students. The five disks orovide t,utornl instruction in (1) . . electron structure. t2J ionic hunding, (3) covalent bonding. 14) the periodic table, and (61the gas laws. Each program in the series provides instruction enhanced by graphs, charts, and periodic tables. The programs then evaluate student progress with questions and prohlems to solve. An incorrect response elicits a brief review of the concept, followed by several more questions andlor problems. At the end of each program there is a test that the student should take. The student scores are recorded in a file to which only the teacher has access. Each time the test is taken variables a n d some of t h e questions are changed, thus preventing students from memorizing answers and retaking the test without understanding the concept. Scores are recorded each time the test is taken al~~~~
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lowing the teacher to know how many times thestudent completed the test. Theseries is not copy protected and permission is granted to make copies for in school use. This program was reviewed and evaluated by high school students in their second year of chemistry. And although the stated intent of the series is to "help students learn and review each of the topics" presented, the students felt that the design and content of the series was effective and useful as a review of first-year topics but did not lend itself to initial learning. Several of the programs contained spelling errors that did not affect function of the lessons. Some of the programs, however, contained errors that would greatly confuse a student who was approaching the material for the first time. T o students using the programs for review purposes, these errors were easily recognized as content errors. While these errors did not hinder the program's effectiveness as a concept review medium, they did tend to reduce the program's credibility. Some of the programs are menu driven, thus allowing the students to choose to review the entire oromam. review onlv certain arena. or to ehailen& the test without orior rrview. This feature wna seen as beneficial aar not inrluded m ell ofthe programs. bu~ Another beneficial feature lacking in some of the program was an "overview" of the program content given before the test. Overall I feel that the Principles of Chemistry series is very useful as a means of reviewing basic concepts. I t should not, however, he used to present new material in a first-year course. The errors in the programs should have heen found and corrected during development. Since the programming is accessible by the user, errors can he easily corrected. ~d M. Powell Liberty High School 100 Liberty Minuteman Drive ~
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Protein Purlflcatlon A. G.800th and B. 0.Hames, IRL Press at Oxford University Press, Waiton Street, Oxford OX2 6DP England
Hardware: Components: Level and Subject:
Macintosh Disk and Manual Undergraduate, biochemistry
Cost:
$150
Summary Ratings: Category
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E m 01 Use: Sublect Msner Conlent: Pedagogic Value:
Excellem
Student Reaclfon:
Untested
Very g o d God
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This software package is designed to simulate the procedures used to purify a protein starting with a protein homogenate resulting from sonicatian, for example, from which the RNA and DNA has already been removed. A set of 20 enzymes are included and the student can select any one of these to purify. In addition, new sets of parameters describing a new protein can he added to the program if desired using the "Mixture Editor". The protein parameters include the thermal stability, the net charge on the protein, the pH range of activity, the molecular weight and charged suhunit composition, the specific activity and the surface hydrophobicity. In ooeration the student selects an unknown.protein to purify and the pH range of enzymatic activity and thermal stability of the enzyme are provided to assist the student in selecting an appropriate purification
Revlewer
Learning Packages
J & S Sofhvare, Principles of Chemistry A. G. Booth andB. D. Hames, Protein Purification EXP: The Scientific Word Processor, Version 2.0
Ed M. Powell Edward R. Birnbaum Thomas H. Richardson
A109 A109 A110
Alan J. Pribula Alan J. Pribula
A112 A112
Bwks John Emsley, The Elements P. A. Cox, The Elements: Their Origin. Abundance, and Distribution Titles of Interest Monographs Continuing Series
Volume 68
Number 4
April 1991
A109
procedure. At this point the student must select a purification procedure from a set of six possible procedures, including ammonium sulfate fractionation, heat denaturation and a variety of chromatographic techniques, including gel filtration, ion enchange, hydrophobic interaction chromatography, ehromatofocusing, and preparative isoeleetric focusing. An extensive selection of chromatographic media are accessible. Affinity chromatography a n d HPLC are not included in the techniques availahle. An info box is available to obtain a brief description of each technique and chromatography media. For each procedure selected the student is askedto provide the appropriate conditions, i.e. the temperature and time of heat denaturation, or the pH range of the elution gradient for a chromatographic procedure. The computer then functions as a technician and determines the results of the procedure, either providing the percent recovery of protein and enzyme activity or displaying the chromatogram, i.e., the absorbance of the eluate at 280 nm versus time. In the latter case you can request an immunoblot or enzyme assay of the fractions in order to determine the location of the protein of interest. After any procedure you can also request a one-dimensional or two-dimensional PAGE gel of any fraction or of the pooled fractions to give you an indication of how pure your preparation has become. Coomassie Blue and immunahlot staining are availahle. A summary of your purification results is presented at the conclusion of each step and ia also available for review at any time. You can also stop the purification and store the results for work-up at a later date. The student can select any combination of these procedures in any order. The test is to obtain the pure protein with the highest yield in the fewest steps and with the least cost. This last feature is an interesting aption. Each procedure has a time and cost factor associated with it. As you proceed through your purification scheme, in addition to getting information regarding enzyme activity and purity of your protein, you are also told how many hours you have spent doing the purification and how much each step costs. If you exceed a preset cost limit, you are chastized for wasting t w much money. Unfortunately, there is no indication of what that preset cost limit is until you actually reach it. The program appears to run well with the usual Macintosh format of buttons and drop down headers. The headings are self-explanatory and I was ahle to run the program successfully without extensive referral to the manual provided. I did find myself becoming irritated with the length of time it took for the chromatograms to appear. After a column procedure has been carried out, the student is asked to select the fractions to be combined for further purification. Instead of giving the student a fixed set of choices by numbering peaks in the chromatogram, the program allows the student to select the fractions by clicking with the mouse along the x-axis. Although I liked this feature of the program I found that I had a tendency to click the mouse prior to the program being ready to accept the position,
All0
Journal of Chemical Education
resulting in a p w r choice of fractions selected. Compoundingthis problem was the fact that you cannot undo that choice after the computer indicated which fractions I had actually selected. A further irritation is the message that flashes on the screen telling you how to select the fractions to pool. This message requires you to answer OK and sppears every time you need to select fractions, whieh occurs for every chromatographic procedure you use. The documentation and operation of the program do not make clear what happens if you repeat a procedure. For example, if you do a 50% ammonium sulfate precipitation followed hy a 35%precipitation on the redissolved pellet, are you getting the results of that combination of steps, or the results of doing a 35% ammonium sulfate precipitstion on the original sample. Another limitation occurs if you use too low a salt gradient to elute a protein; you are not provided with an opportunity to increase the salt concentration further in order to elute your protein off the column. Instead you have lost your protein and have to start over. Some minor problems encountered are as follows. Closing the gel window quits the program, rather than just restoring you to the main menu. When you are done with a purification there doesn't appear any way to start a new purification without quitting and restartine the nromam. Finallv. " .. although there is a dilution step avnilnhle in case the ahaort,ance of your prutein solution is coo high, there is no concentration step available in case the protein solution hecomes too dilute. The latter possibility would seem to he more of a problem than the former. The Dromam comes with a 44-naee . .. manual which gives a general deacriptim of the program, a set of figures showing the appearance of the monitor at various puinu :n the program and a summary of the strategy and techniques of protein purification. The program does an excellent job of demonstrating haw various protein purification techniques work, i.e., what you have to do to earrv them out and what the end results loo
