Ph.D. Procedures

Research Rotations

Doctoral students supported by an NC State University teaching or research assistantship are required to participate in a minimum of two research rotations (carried-out from July through the fall semester).

We place emphasis on students obtaining sufficient familiarity with research operations and goals in laboratories of faculty so that they can choose and pursue a research topic of high interest. Faculty also become familiar with the new graduate students in the program. The student may choose a laboratory for their thesis or dissertation research following the last rotation period. If necessary, they may participate in an additional rotation, following consultation between the student, the director of graduate programs, and the respective faculty. Students receive 1 credit of MB 670/870 for two laboratory rotations. Student performance during each rotation is evaluated by the principal investigator of the laboratory. Evaluation will include an assessment of laboratory performance and a written or oral report by the student on their rotation experience. Satisfactory performance in the laboratory rotations conducted will be required to receive credit for MB 670/870. Students supported with a stipend funded from a faculty grant or targeted resources are not required to participate in the laboratory rotations but may do so by arrangement with the principal investigators. Students are encouraged to review the faculty research pages and to meet with faculty before deciding upon the specific labs in which the rotation is carried out.

Doctoral Preliminary Exam Procedures

Before the first day of spring semester classes in the third year in the microbiology Ph.D. program, students will have completed the requirements of the preliminary exam, which is centered around a research proposal. The exam will consist of two parts, the written proposal and an oral defense by the student before the members of the Advisory Committee.

The Written Preliminary Examination – A Research Proposal (Part A)

The preliminary examination process will begin around the summer at the end of the second year the student is matriculated in the program. The student will write and submit a research proposal to the advisory committee. The proposal’s subject matter will be tangential to, or distinct from, the student’s anticipated thesis research.

The student will submit two or more pre-proposals to the advisory committee that include a background and significance statement and a list of specific research aims. At this stage, students are encouraged to consult with the thesis advisor or other committee members. The advisory committee will select one of the pre-proposals for the full proposal; changes in aims can be made by the committee at this time. The committee has two weeks to provide a response to the pre-proposal. The student must prepare the proposal in the format of a National Institutes of Health (NIH) research proposal, but approximately 15 single-spaced pages long, including figures (but not the literature cited).

See the guidelines below for the format of the written proposal.

At this stage, the student should develop and write the proposal independently. At least six weeks prior to the date of the oral defense, the student will submit the proposal to the advisory committee. The committee will have two weeks to evaluate the proposal. The committee members will provide a written evaluation of the proposal to the student, to other members of the advisory committee and to the DGP. The committee will determine the status of the written preliminary examination as:

  • Pass: the student has satisfactorily completed the written examination and can schedule the oral exam (within two to three weeks);
  • Conditional Pass: the student provides written responses to concerns from each committee member, meeting with each member as needed (two weeks to complete). Each response is distributed to all advisory committee members and to the DGP. Committee member(s) have two weeks to respond with a pass, conditional or fail to the DGP;
  • Fail: the DGP alerts all committee members that a fail on the written exam evaluation was submitted. The advisory committee determines the opportunity for the student to repeat the written examination (within one week).

The Oral Preliminary Examination – Defense of the Proposal (Part B)

The oral preliminary examination is scheduled within two to three weeks of satisfactorily passing part A (written exam). Appropriate slides and handouts to be used by the student in the oral will be provided to the committee members two days in advance of the oral exam. The student will give a brief (20-30 minute) oral presentation describing the research proposal and then respond to questions from the advisory committee. The questions will focus on the research proposal but may include any question relevant to it or to the expected proficiencies in microbiology. Following the examination, the advisory committee will decide whether the student:

  • Passes the exam unconditionally and proceeds to candidacy;
  • Passes the exam conditionally and must complete additional work to satisfy a perceived deficiency;
  • Fails the exam.


After the student passes the preliminary examination (Part A and B), the advisory committee and DPG will sign the Graduate School documents certifying candidacy for the Ph.D.

Procedure for Appeal

Appeals of a decision by the advisory committee must be made to the MGP within two weeks or they will be final. The MGP will make the final decision on an appeal. A student who has not satisfied the preliminary examination requirement within 36 months of entering the Ph.D. program will be dropped from the program, except by appeal in writing to the MGP, who will make the final decision.

Written Preliminary Format

Preparation of Research Proposals for the Microbiology Preliminary Examination

This outline provides guidance for students to the form and function of research proposals. The model used is the NIH plan for public health service grants. As in the case of a real proposal, you should persuade a reviewing group that:

  • your goals are interesting and important;
  • you have chosen a plan of experimentation that is highly likely to return interesting and interpretable results in a reasonable timeframe;
  • you have the background and understanding to bring this plan to fruition.

Plan on writing the proposal as you would for a two- or three-year postdoctoral project.

Clarity is important in a proposal. Not all of the people who review it will be experts in your field, therefore, you must provide significant information to document the above goals to this group. You should avoid unnecessary arguments and information, as they will distract from the essential arguments.

Because you will actually be judged on the final version of the proposal and your defense of it, it would obviously be prudent to generate as good a proposal as possible for submission to your committee. It is therefore reasonable that you begin the overall outline of the proposal well before the fact and discuss the goals and approaches with colleagues. To this end, you will prepare at least two pre-proposals, each of 1 –2 pages long, that will allow the committee to assess your focus and strategic plan. One of these will be chosen as the topic of your full Research Proposal. You are encouraged to consult with your advisor, committee members and colleagues at the pre-proposal stage. After the pre-proposal, the proposal itself should represent your independent efforts.

The proposal description below contains information about the overall structure of the proposal as well as suggestions about each of the individual sections. You will be writing a proposal that can be accomplished as a postdoctoral requesting a 2 – 3 year funding period. You should follow the format for an NIH NRSA Individual Postdoctoral Fellowship (F32); NIH provides form 416 and instructions online. If you have further questions, contact the director of graduate programs (DGP) for the MGP.


This is the critical initial contact with the reader. Distill the necessary parts of your proposal to a one-half page or less, stating the problem and what you intend to do about it. Make it understandable to the intelligent, but inexpert, reader.

Specific Aims

List the major questions that will be answered in your research and the specific approaches that will be used to address those questions. This is typically done in an outline form of no more than one-half page. It should also provide the framework for the Experimental Design section below, so its organization is key to the entire proposal. Try to be realistic and propose an amount of work that you are likely to accomplish in the next 2-3 years; excessively optimistic proposals suggest a lack of critical thought.

It is often advisable to divide the following sections into subsections with titles to orient the reader.

Background and Significance

This section should be several pages long and contain enough information to make the subsequent sections understandable to the reviewer. It should also give the reviewer an understanding of the state of the field before your participation. It should, therefore, cite any critical information that is either published or known to you through personal communication. This section should also serve to convince the reviewer that the general question chosen is an important one.

Previous Results

Preliminary data can be described in this section, but as this is not the exact research project you can use the most recent of published data to establish the current status and take-off point for your proposed projects. The goal of this section is to convince the reader that “you” have made some progress and/or that you have skills that will be necessary to complete the proposed work.

Experimental Design

Typically the sections in this part will follow in the order laid out in the specific aims. The goal here is to convince the reviewer that your approach will yield interpretable results and that you understand those approaches. If there are intermediate goals that are critical to the whole project, either defend why your single approach must work, or propose alternative approaches. Provide enough information to make it clear that you understand the technique; this does not mean an abundance of detail, but a terse description of potential problems and shortfalls in the experiment or its analysis. If there are obvious experiments that will not be done, tersely say why.

Make your priorities clear; not every experiment is as important as the next, and some approaches will be pursued only under certain circumstances. Continually orient the reader by explaining how each intermediate goal fits into the overall plan.


This short section should be a realistic estimate of when the critical intermediate goals in the proposal will be accomplished. It should also make clear when the primary approaches will be dropped and the alternatives adopted. You wish to convince the reviewer that, no matter what happens, you will return with a “story” in a reasonable time period. Plan on writing the proposal as you would for a two- or three-year postdoctoral project and that the goals will be met in this time frame.

Literature Cited

Using a standard format (authors’ names and journal citation, including titles), list the references cited throughout the proposal. This should not only document your understanding of the state of current information but also that you know the critical sources of information on the methods you have proposed to use.

Overall Format

You will follow the NIH postdoctoral NRSA application overall format. Keep the proposal, including figures and tables, but not the Literature Cited, to no more than 15 single-spaced pages. Use 1″ margins, 12-pt type, and page numbers throughout the proposal.