3.8 Research journal article--Experimental Section/Model Description
This section, which is sometimes called Materials and Methods/Experimental/
Methods/Procedures/Model Description must be written so that an informed colleague can repeat the same experiments or follow the same model to confirm your results. The decision as to how much detail is necessary can usually be made if this is kept in mind.
9.1 PAIL for the Experimental Section of your research article
P | Provides information for confirmation of materials and methods used |
A | Is a colleague who can, if necessary, repeat your experiments |
I | Gives sufficient detail for repetition of experiments |
L | *Follows the conventions for numerical units and format details specified by the journal *Usually uses verbs in the past tense for description of experimental procedures(an exception is a paper reporting on the development of a new method; in such a case, the present tense is sometimes used instead.) *Usually uses present tense/command form when describing model |
Check the Instructions to Authors for the journal in which you wish to publish and examine the Experimental Procedures/Model Description section of a sample paper from a recent volume.
This section is usually not too difficult. However, the following exercise shows some examples of problems which can arise.
9.2 Exercise: What is wrong with the following? Can you correct them?
1. | E. coli strains Y1008 was used for the work. |
2. | Poly (A)+ mRNA was purified by a oligo(dT)-latex. |
3. | Analytical grade potassium hydroxide and octyl mercaptan was used without further purification. |
4. | Total RNA was isolated using guanidine thiocyanate method described by Smith et al. |
5. | Root masses were harvested from plants grown in liquid medium containing X mixture, and adjusted the pH to 5.7 with KOH. |
6. | The library was screened through functional complementation. |
7. | The used DVB included ethylvinylbenzene and diethylbenzene. |
8. | PXy particles were observed with the optical microscope. |
Many of the problems in the Experimental Section are related to the proper use of prepositions and particles used with the verbs. One way to solve this problem is to prepare your own glossary of terms from papers in your field. For example, 9.3 shows some terms from a paragraph from an Experimental Section. Note which prepositions are used with which verbs.
raised | from | seeds |
excised | from | a plant |
cut | off from | the pulvinus |
leaving | the petiole | |
immersed | in | a bathing solution |
used | in | this experiment |
developed | by | Okamoto et al. |
measuring | the response | |
shown | in | Fig. 1 |
inserted | into | a flexible silicon tube |
mounted | into | an opening |
held | in place with | a Teflon cover nut |
sealed | together with | epoxy-resin glue |
9.3 The procedural action verbs and their particles from the first paragraph in another paper are shown in 9.4.
9.4 Procedural action verbs for first paragraph of a Materials and Methods section.
Subject | Verb | Preposition | Object |
the material | was obtained | from | the Smith Company |
specimens | were utilized | in | all desorption tests |
samples | were cut | from | the as-received coil of wire |
(were) straightened | by | hand | |
hydrogen | (was) charged | into | the material |
samples | were ground | with | paper |
(were) rinsed | in | acetone | |
(were) cleaned | in | methanol | |
(were) weighed | |||
(were) tested |
Here are some other examples from other papers.
9.5.
Verb | Preposition | Object |
carried out | in | X reaction vessels |
eluted | from using | the column a linear gradient |
kept | under | low-temperature conditions |
performed | with | a chromatograph |
prepared | by using with | A the method of B stirring |
purchased | from | XYZ Chemical Co. |
recrystallized | in | ethanol |
subjected | to | chromatograph analysis |
synthesized | for by | A B |
used | for | chromatograph separation |
was | a gift from A |
Another type of section found in engineering papers is the description of the model used for the study.
Here are some examples of expressions often found to describe models. Note the use of present tense or the command form.
Verb | Tense | Example | |
1 | allow | Pres | The declarative definition allows the direction of resolution to be indicated by the variables that... |
2 | define | Pres | The absorption-line blackbody distribution function is defined as ... |
3 | define | Pres | The NNN equations in Cartesian coordinates can be written in the following form....where U, E, R, and G are suitable defined vectors, representing the mass, momentum, and energy equations. |
4 | perform | Pres | The subscript i refers to the ith spectral segment and the summation is performed over all segments covering the entire spectrum. |
5 | provide | Pres | The absorption-line blackbody distribution function provides the means for... |
6 | represent | Pres | The NNN equations in Cartesian coordinates can be written in the following form....where U, E, R, and G are suitable defined vectors, representing the mass, momentum, and energy equations. |
7 | write | Pres | The NNN equations in Cartesian coordinates can be written in the following form....where U, E, R, and G are suitable defined vectors, representing the mass, momentum, and energy equations. |
8 | let | Com | Let us consider the general case first, exemplified by the following list of abstract cases and their categorial classification: |
9 | note | Com | Note that the function... only defines the spectral dependence. |
10 | suppose | Com | Suppose that the sequence of numerals ... represents... |
Find examples from the Experimental Section/Model Description section of your reference paper(s) and note their features. Give some examples here.
Materials and Methods & Results
