Scientific Literature

Scientific Literature and Peer Review

The scientific literature is the backbone of all original inquiry in the sciences. The literature provides a permanent foundation upon which future experimentation can be based. The strength of the scientific literature is maintained by the process of peer review, which allows independent experts in a researcher’s field to confirm the soundness of an experiment’s design and execution and the appropriateness of the researcher’s interpretation of experimental results before the report is published.

The scientific literature can be subdivided into two categories:

  1. Primary literature – consists of first hand reports of experimental results in professional journals. These reports include detailed information concerning the experimental methods and results, as well as the researcher’s interpretations of those results. Primary literature articles should contain adequate details to allow an independent laboratory to repeat the investigation. Recently published primary literature represents the most current understanding in a given field.
  1. Secondary literature – consists of second hand reports such as review articles and textbooks. These sources are used to condense the findings presented in the primary literature so that one can quickly grasp the level of current understanding in a field.

Format of Scientific Papers

When researching a subject it is important to be familiar with the primary literature. Primary literature follows a fairly strict format that allows one to quickly find the relevant information in an article (i.e. background, methods, statistical methods).

  1. Title – a short description of the contents or major findings of the paper.
  1. Abstract – a short (100-200 words) summary of the content of the paper including the hypothesis, methodology, results and conclusion(s).
  1. Introduction – provides background (a short history of previous findings in this line of research) and the purpose of the research, or the hypothesis (the question that the research seeks to answer).
  1. Material and Methods – a detailed description of the equipment and techniques used to perform the experiments (to test the hypothesis). Includes specifics about animals, chemicals, statistical tests, surgery, etc… Material and methods should be detailed enough that an experienced researcher should be able to repeat the experiment.
  1. Results– thedata are presented in this section without interpretation. Data are presented in the “Results” section in two ways, a written description and graphically in the form of figures, tables and/or graphs. The data should address the hypothesis being tested. Figures and graphs should be clearly labeled and have a written description in associated figure legends.
  1. Discussion – the data are interpreted in this section. The discussion is a synthesis of the background presented in the introduction and the results. Often the new data is compared with previously published data. This is where the conclusions are stated and results summarized. Future directions of research are suggested.
  1. References – all ofthe published books, papers, reports, etc.. cited in the paper. In general, these are listed in alphabetical order by the first author’s last name. The date that the article was published is also included so that you can follow the chronology of the research and know "who discovered what, when". The references help you locate other sources and provide names of people doing active research in specific fields. You can use these names when searching computer databases to locate the most recent publications.

8.Acknowledgments –this short section is sometimes optional. It lists individuals that played relatively minor roles in generating the publication (i.e. technicians, interns). More importantly, the source of funding that supported the research is indicated here. Major funding agencies include The National Institutes of Health and National Science Foundation.

Assignment # 1: Using Primary Literature Resources

  1. Use Medline, Science Direct, Biological Abstracts or another search engine to locate a recent (1999-present) primary literature article (on a physiologically relevant subject) that has been posted on the Internet in full-text format. Print out a full copy of the article.

OR

Use Woodward Library to search for the article in a journal and photocopy the article.

  1. The article must be a primary report of an experimental investigation. Review articles are not acceptable for this assignment!Be prepared to look at many different articles and journals. Some very technical topics may be difficult for you to understand. Use secondary literature such as your textbook or scientific/medical dictionaries to look up terminology and general background.
  2. Read the article carefully and on a separate paper (to be turned in for a grade) provide the following information.

A. Authors and institutions

B. State the hypothesis.

C. Briefly describe the methods.

D. Briefly describe the results.

E. Briefly describe the conclusions.

F. Who supported the research? (Sometimes this information is not published).

  1. Next, find one of the primary articles that was referenced in the first article.
  2. Read this article with respect to why it was referenced in the first article. On a separate piece of paper, write one paragraph which details why it was important for the first author to use this article as a reference. Attach a photocopy of the front page or the Abstract of this article to the assignment.

Your complete assignment must include these items:

A hardcopy printout of the entire online journal article or a photocopy of the one you found at Woodward Library.

A page detailing the information on the article specified above.

Your analysis of why the authors of the first paper chose to reference the earlier paper.

A copy of the title page or Abstract of the primary research article.

 Remember: If your article does not have distinct “Methods” and “Results” sections, you probably do not have a primary literature article!

General Lab Write Up Instructions:

Lab reports may be handwritten, copied and pasted by computer, or reformatted by computer. Be sure to follow space restrictions. This is a general guideline to complete the lab reports provided in the manual. Your last lab will follow a more extensive formal lab report format as described below.

Introduction:

Clearly and briefly define the nature of the investigation by bringing attention to: (1) the specific purpose of the research, (2) the hypothesis tested, and (3) the significance of the problem. The introduction is not meant to be an exhaustive review of the subject, rather, it should quickly draw attention to the reasons the experiment was conducted.

  • Include a CLEAR STATEMENT OF PURPOSE
  • Summarize the important concepts studied in the lab – use the Discussion section questions to help you determine what is important
  • Use complete sentences: “The purpose of the lab was to…” or “In this lab we tested…in order to show that…”
  • Do NOT copy the Objectives section of the lab manual

Materials and Methods:

For the general lab reports, you do not need to rewrite the materials and methods sections from the lab manual. Simply reference the lab manual. You must include any changes or additions made to the lab so that anyone repeating the lab would do exactly as you did if they followed the lab manual and your report.

  • Include and changes made to the lab – omitted sections, changes in timing of procedures, changes in materials used, changes in quantities used, errors made in performing the experiment.
  • If you borrow results from another group, include this here
  • Use the past tense for this section

Results:

This is a summary of the data collected during the investigation. This section needs to include tables and graphs where appropriate and a written summary of the results that guides the reader to the individual figures and illuminates basic trends in the data. The “Results” section should NOT include any interpretation of results.

  • Include results on separate pages
  • Graphs and tables may be completed by hand or on the computer. If creating graphs on the computer, be sure you are absolutely familiar with your computer graphing program
  • Use good graph paper (mm line divisions – engineering graph paper)
  • Data is normally represented in either a table or a graph. Generally, tables can display more information, while graphs are important in displaying important trends. The general lab report instructions will often include both a table and a graph for the same data for practice.

Graphs:

  • Graphs and sketches are ‘Figures’ in the lab report.
  • Label figures with a number and title: ‘Figure 1: The effect of solutes of varying….’
  • Figure titles MUST be placed under the figure.
  • Figure titles MUST be descriptive. Include sufficient information in the title such that what is shown in the graph is easily understood simply by reading the title. Do NOT use versus in the title (ie. Hemolysis time versus molecular weight).
  • Choose an appropriate size graph – it is not necessary to use the whole graph paper
  • Decide if a scatter, line or bar graph should be used depending on the type of data
  • Scale:

-Choose appropriate scale divisions so that the data are displayed effectively

-Choose a scale that prevents large gaps, keeps the graph to an appropriate size, and allows you to observe trends

-Only use scale breaks if absolutely necessary. Try not to use more that one break per axis. Be sure to continue the same scale divisions on either side of the scale break.

-Continue your scale past your last data point

  • Label the axis with a title and include the units
  • Include a legend if necessary to distinguish different data points/series using colours, symbols, etc. Include the legend to the side or under the graph.
  • Include a brief description of the results under the figure and figure title. This should include what trends are observed. Explanations of why something happens are saved for the discussion. Refer to the figure in the explanation. Also, if results are unexpected, explain this here (ie. We observed a faster rate of hemolysis with glycerol as compared to urea. We would have expected hemolysis to occur more quickly with….).
  • Two graphs may be combined in one Figure. In this case, use one figure title and indicate one graph as (a) and the other as (b) in the same figure (ie. Figure 3: The effect of (a) lipid solubility and (b) molecular weight on time to lysis of bovine red blood cells).

Example Graph:

Figure 1: A comparison of changes in heart rate and workload achieved in ten male cyclists during a maximal exercise test.

Tables:

  • Label tables with a number and title: ‘Table 1: Times to hemolysis of bovine red blood cells and the solutes used including the molecular weight and partition coefficient of each solute.’
  • Table titles MUST go above the table.
  • Table titles MUST be descriptive.
  • Include appropriate column and row headings and units. Do NOT place the units beside each value in the table.
  • Round off numbers to the correct number of decimal places

Example Table:

Table 1: Heart rate and workload measurements for ten male cyclists during a maximal exercise test.

Time / Heart Rate / Workload
(minutes) / (beats/minute) / (watts)
0 / 109 / 0
3 / 126 / 90
6 / 149 / 180
9 / 170 / 270
12 / 191 / 360

Recordings:

  • Chart recordings are ‘Figures’ in the lab report
  • Label figures with a number and title: ‘Figure 1: Electromyogram of the gastrocnemius muscle of a bullfrog showing…’
  • Figure titles for chart recordings MUST be placed under the figure.
  • Figure titles for chart recordings MUST be descriptive.
  • Label the recordings with appropriate equipment settings (ie. chart speed, stimulation voltage, stimulation frequency, etc.)

Discussion:

This section consists of your interpretation of the data. The results of your experiment must be interpreted with respect to your purpose and the original hypothesis.

  • Interpret YOUR results. Refer to your data and explain unexpected results if necessary.
  • Read the questions carefully and answer what is being asked.
  • Use the space limitations. You do not need to write an essay.
  • Use complete sentences and proper grammar.
  • Keep your answers simple – you do not need to use big words and complicated terminology.

Other Considerations:

  • Staple your lab report before you come to class.
  • Do not put your report in a binder.
  • The lab report should be written in past tense and using the passive voice.
  • Do not use short forms such as @, b/c, &, and so on.
  • Use correct spelling and grammar – have someone check your writing if your grammar skills are not strong.
  • If using a short form such as RBC for red blood cells, or HR for heart rate, you must introduce this short form the first time you use it in your report. (ie. When the red blood cells (RBC) were placed in a isosmotic solution of….). From this point on in the report you can then use the short form.
  • Keep things neat and well organized.
  • Do not cram too much on one page.

Plagiarism:

The lab experiment and data collection are meant to be a group effort. The lab report is meant to be an individual effort. You may discuss how you should write the report with other students. You may work together to analyze the results and discuss how to make the appropriate graphs and exchange papers for peer review, but in the end you need to create your own tables and graphs, compose your own answers, and write your own report.

  • Each student must hand in their own lab report.
  • Do not copy from the textbook – you must use quotations if you do this.

Final Laboratory Report Format

The final lab report will be prepared following formats found in the scientific literature. Students are encouraged to examine the style of reports in the primary literature for ideas on how to best prepare their reports.

 Scientific reports are generally written in the past tense and using the passive voice.

Required elements for all written lab reports:

1)Title – Should be short, but descriptive. “Cardiac Physiology” would not be an acceptable title, because it is not descriptive. A better choice would be: “The effects chemical and thermal stimuli on cardiac performance.”

2)Abstract – Summarizes the entire lab report in 200 words or less. Should include the purpose of the investigation, a short (1-2 sentence) description of methods, the primary results and the fundamental conclusion.

3)Introduction – Clearly defines the nature of the investigation by bringing attention to the specific purpose of the research, the hypothesis tested and the significance of the problem. Should contain referenced background on the specific field of study and on the basic problem(s) that the investigation addresses. The introduction is not meant to be an exhaustive review of the subject, rather, it should quickly draw attention to the reasons the experiment was conducted. Points will be deducted if:

a)There is not a clear statement of purpose.

b)There is not referenced background information.

c)Extraneous background material is included.

d)Results and/or conclusions are addressed in detail in the introduction.

4)Materials and Methods – Summarize the procedure, in your own words, including a brief description of equipment and specimens. Use specifics whenever possible. Make sure this section is written in the past tense! Points will be deducted if you:

a)Copy the procedure directly from the lab instructions.

b)Present this section in a bulleted or numbered list. This section should be written in paragraph form.

c)Include inaccurate procedures.

d)Address results and/or conclusions in the “Methods” section.

5)Results – Summarizes the data collected during the investigation. This section needs to include tables and graphs where appropriate and a written summary of the results that guides the reader to the individual figures and illuminates basic trends in the data. The “Results” section should not include any interpretation of results. Points will be deducted if:

a)Data are not summarized in appropriate paragraph form.

b)Interpretations of data are presented in what is meant to be a pure “Results” section.

c)Necessary tables and graphs are not included.

d)Tables and graphs are not numbered and titled, or not referred to in the text by number. Table columns do not contain appropriate labels. Graphs are not appropriately labeled with axes or legends.

6)Discussion – This will be the most heavily weighted section of your lab report. This section consists of your interpretation of the data. The results of your experiment must be interpreted with respect to your purpose and the original hypothesis. Primary literature references should be used to compare and contrast the results of your endeavors with accepted theory and the results of related investigations. This is also a good place to explore potential problems presented by the experimental method or to open up questions that arise from your results and to postulate about what future steps should be taken. Points will be deducted if: