A gap is something that remains to be done or learned in an area of research; it’s a gap in the knowledge of the scientists in the field of research of your study. Every research project must, in some way, address a gap–that is, attempt to fill in some piece of information missing in the scientific literature. Otherwise, it is not novel research and is therefore not contributing to the overall goals of science.
Identify the gap.
A gap statement is found in the Introduction section of a journal article or poster or in the Goals and Importance section of a research proposal and succinctly identifies for your audience the gap that you will attempt to address in your project.
A gap might be a lack of understanding about how well a particular instrument works in a certain situation. It could be introducing a new method that needs to be tested. Or it could be that you are studying a whole new organism, system, or part of a process. Your project may also address multiple gaps, in which case you should be sure to identify each of them clearly!
In a class, you might not always be studying something brand “new.” But, in most cases, you should still try to come up with something unique about your project, however small. Talk to your professor about what they expect for your gap statement if nothing seems to work.
|
An example gap from Hosaka, Itao, and Kuroda (1995): “… The relationship between the four damping factors, i.e. internal friction, support loss, airflow force in free space, and squeeze force, has not yet been clarified, so it is not obvious which one is dominant in actual microsystems.” |
Here, the authors signal to us that this is a gap because they use the words “has not yet been clarified.” Other phrases that might help you identify (or form!) a gap statement are:
- …has/have not been… (studied/reported/elucidated)
- …is required/needed…
- …the key question is/remains…
- …it is important to address…
Fill the gap.
Once you identify the gap in the literature, you must tell your audience how you attempt to at least somewhat address in your project this lack of knowledge or understanding . In a journal article or poster, this is often done in a new paragraph and should be accomplished in one summary statement, such as:
Therefore, the purpose of this study was to determine the effects of lead on the hepatobiliary system, especially on the liver and on the gallbladder (adapted from Sipos et al. 2003).
You’ll often find that the first sentence of the last paragraph in a paper’s introduction will start somewhat like this, indicating the gap fill.
Some phrases you can use to indicate your gap “fill:”
|
Remember–always keep your voice professional! Colloquial phrases such as “we looked into” or “we checked if” should be avoided when introducing your gap fill.
So let’s look at this idea in context by looking at some examples from a couple of types of papers. The gap statements are underlined; the fills are italicized.
| Adapted from Monthioux et al. (2001):
Though ideally expected to be chemically very stable due to the poor reactivity of the basal aromatic plane from which SWNTs are built, the question of whether all the chemicals which are now currently proposed in the literature as purifying, suspending, or grafting agents for SWNTs actually have a limited effect on the SWNT integrity has to be addressed. In this paper, we report the investigation of the effects of some commonly used chemical treatments on SWNT structure by means of high resolution transmission microscopy (HRTEM). We also report the effect on purified SWNTs of an organic solvent, dimethylformamide, used to tentatively prepare SWNT suspension. Adapted from Zhang, Dawes, and Walker (2001): Milly’s work recognized the importance of storage capacity of the root zone in controlling evapotranspiration and has the postential for assessing the catchment-scale response of vegetation changes. However, the practical application of this model is limited because of the complex numerical solutions required. The purpose of this paper is to quantify the long-term impact of vegetation changes on mean annual evapotranspiration at catchment scales based on data and parameters that are easily measurable at a regional scale. Adapted from Lecoanet, Bottero, and Wiesner (2004): A risk assessment of the potential impacts on health and environment that the production, use, and disposal of nanomaterials may engender requires information concerning both the potential for exposure to a given material and its (once exposed) potential impacts such as toxicity or mutagenicity. In this work, we address the issue of nanomaterial exposure and transport in experiments designed to assess their potential for migration in porous media such as groundwater aquifers and water treatment plant filters. |
In the second and third examples, the gap may be a little less obvious–it doesn’t use any phrases to signal to you that there’s something missing, such as “has not been clarified” or “have not been reported.” But because of the way the paragraph is laid out–following the conventions of our move structures–we can see that the underlined section of text is indeed the missing information in the literature that the group sought to address in their project.
[bg_faq_start]
Test yourselfIn the following examples, identify the gap statement. Then, identify the fill. Notice if there are any specific words or phrases used to signal either of these moves. 1. Adapted from Costa, Robertson, and Quilliam (2015): Paralytic shellfish poisoning occurs worldwide, and harmful algal blooms, including those responsible for PSP, appear to be increasing in frequency and intensity. PSP outbreaks in Portuguese waters have been associated with blooms of Gymnodinium caenatum in the late 1980s to early 1990s, then again after 2005. According to the national monitoring program in Portugal, G. catenatum were not reported along the Portuguese coast during the 10-year period from 1995 to 2005. The aims of this study were to fully characterize the toxin profile of G. catenatum strains isolated from the NW Portuguese coast before and after the 10-year absence of blooms to 2. Adapted from Littler, Ciringh, and Lindsey (1999): The exchange process frequently observed in polypyrrane condensations is proposed to occur by the acid-catalyzed fragmentation of a polypyrrane 1 into pyrrolic 2 and azafulvene 3 components.15 As illustrated in Scheme 2, recombination of 2 and 3 can form a new polypyrrane 4 that cannot be formed by direct condensation of the dipyrromethane and aldehyde. Ultimately this process leads to the production of a scrambled mixture of porphyrins. The factors that promote the scrambling process in MacDonald-type 2 + 2 condensations are poorly understood, but suppression of scrambling is essential for preparing large quantities of pure trans-porphyrins. In this paper we describe a study of a wide range of reaction conditions for the 2 + 2 condensation that has led to refined synthetic procedures for the preparation of trans-porphyrins. 3. Adapted from Pukhov and Meyer-ter-Vehn (2002): In the present paper, we focus on laser wake field acceleration in a new, highly non-linear regime. It occurs for laser pulses shorter than λ(p) but for relativistic intensities high enough to break the plasma wave after the first oscillation. In the present relativistic regime, one should notice that the plama wave fronts are curved and first break new the wave axis and for lower values than the plane-wave limit. This has been studied in 2D geometry in [14-17]. Here, we present 3D PIC simulations of two representative cases. The case (I) is just marginally above and the case (II) is far above the breaking threshold. [bg_faq_start] SolutionsGood gap and fill signaling phrases are italicized.
1. Gap statement: “The factors that promote the scrambling process in MacDonald-type 2 + 2 condensations are poorly understood….” Fill: “In this paper we describe a study of a wide range of reaction conditions for the 2 + 2 condensation that has led to refined synthetic procedures for the preparation of trans-porphyrins.”
2. This question is a little trickier! The authors use “In the present paper…,” then, “In the present regime…,” and finally, “Here…,” all of which sound like signaling words for filling the gap. But where is the gap? We have to look closely at what exactly is being said. It is true that the first statement appears to be somewhat of a gap fill, although they haven’t yet given us a gap statement. The authors go on to say “This has been studied in 2D geometry,” which brings us back to move 1(iii), identifying critical evidence from the literature. Thus, the gap statement is not explicit. It is a combination of stating that this concept has been studied in 2D, followed by announcement that the authors will study it in 3D. Although the first sentence (“… we focus on laser wake field acceleration…”) could also be considered part of the fill, because it comes before the gap statement and is also less descriptive, it functions more as an introduction to these moves.
3. Gap statement: “According to the national monitoring program in Portugal, G. catenatum were not reported along the Portuguese coast during the 10-year period from 1995 to 2005.” Fill: “The aims of this study were to fully characterize the toxin profile of G. catenatum strains isolated from the NW Portuguese coast before and after the 10-year absence of blooms to
[bg_faq_end] |
[bg_faq_start]
Practice exerciseFind 3-4 primary research articles (not reviews) from reputable journals in your field. Underline the gap statement and circle the gap fill. Remember that not all papers follow this exact move structure, so if you can’t seem to find either of these moves, you might have to look carefully at different parts of the introduction and ask yourself:
[bg_faq_end] |