Classic Research Articles as PBL Problems

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Classic Research Articles as PBL Problems

• Hal White
• Dept of Chemistry and Biochemistry
• University of Delaware
• Case Study Teaching in Science
• 7 October 2005
• Buffalo, NY

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Introductory Science Courses Stereotype

• 1. Lecture format that is content-driven.
• 2. Abstract concepts introduced before concrete
  examples.
• 3. Enrollments typically more than 100.
• 4. Limited student-faculty interaction.
• 5. Grading based on a few multiple choice
  examinations that emphasize recall of
  information.
• 6. Reinforce intellectually immature students to
  a naïve view of knowledge.

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What do we teach in science?

• Much of our educational system seems designed to
  discourage any attempt at finding things out for
  oneself, but makes learning things others have
  found out, or think they have, the major goal.
• Anne Roe (1953)

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Common Features of a Problem-Based Approach to
Learning

• Learning is initiated by a problem
• Problems are based on real-life, open-ended
  situations.
• Students identify and find the information
  necessary to solve the problem using appropriate
  resources.
• Students work in small permanent groups with
  access to an instructor.
• Learning is active, integrated, cumulative, and
  connected.

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Overview

• The Case for Classic Articles as PBL Problems
• Example of an Article-Based Course
• Experience a Classic Article Problem
• Designing a Course Around Classic Articles
• Student Response

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Characteristics of Good PBL Problems

• Engage interest
• Require decision and judgement
• Need full group participation
• Open-ended or controversial
• Connected to prior knowledge
• Incorporate content objectives

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Classic Articles as PBL ProblemsAdvantages

• Authentic (not contrived)
• Complex
• Relevant to the Discipline
• Introduce Important Historical Figures
• Encourage use of Library

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Science as Literature?

• There is no form of prose more difficult to
  understand and more tedious to read that the
  average scientific paper.
• Francis Crick (1995)

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Science as Literature?

• I am absolutely convinced that science is vastly
  more stimulating to the imagination than are the
  classics, but the products of this stimulus do
  not normally see the light of day because
  scientific men as a class are devoid of any
  perception of literary form
• J. B. S. Haldane

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What is a Classic Article?

• It is indeed rare for a scientific paper to
  remain central to current concerns several
  decades after its publication in general, papers
  decay like last winters leaves or this summers
  pop songs, and scientists instead cite the latest
  review paper.
• Edward Ahrens (1992)

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How can we connect students to their discipline?

• Only by understanding the difficulties
  encountered in trying to do what now seems simple
  can a student appreciate the hurdles which must
  be surmounted in modern experiments of which we,
  for the most part, hear only the conclusions
• James Bryant Conant (1946)

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Introduction to BiochemistryEvolution of the
Course

• 1970's Course for non-science majors based on
  Herman Epsteins model.
• 1989 Modified course initiated as part of a new
  B.S. Biochemistry curriculum.
• 1993 Problem-Based Learning format introduced.
• 1996 Undergraduate Tutor-Facilitators used for
  the first time.

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Introduction to BiochemistryAn Article-Based
PBL Course

• 3 Credits, No Laboratory, 800 AM MWF
• Theme - Hemoglobin and Sickle Cell Anemia
• First Biochemistry Course for Sophomore
  Biochemistry Majors
• Required for the Major
• Taught in a PBL Classroom
• Enrollment 20 - 35
• Uses Juniors and Seniors as Group Facilitators

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Introduction to BiochemistryCourse Description

• Heterogeneous groups of 4 discuss and work to
  understand about ten classic articles.
• Articles presented in historical context, show
  the development of scientific understanding of
  protein structure and genetic disease.
• Assignments and examinations emphasize conceptual
  understanding.
• Instructor monitors progress, supervises tutors,
  presents demonstrations, and leads whole class
  discussions to summarize each article.

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Introduction to BiochemistryInstructional Goals
For Students

• Become intellectually independent learners
• Recognize and confront areas of personal
  ignorance
• Review and apply chemical, biological, physical,
  and mathematical principles in a biochemical
  context
• Improve problem-solving skills
• Create, understand, and value abstract
  biochemical models
• See biochemistry in relevant historical and
  societal contexts
• Discover and use the resources of the library and
  the Internet
• Gain confidence in reading and understanding
  scientific articles
• Experience the powers (and pitfalls) of
  collaborative work
• Appreciate importance of clear oral and written
  communication
• Learn to organize logical arguments based on
  evidence

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Oxidation and Reduction of Hemoglobin
CHEM-342 Introduction to Biochemistry
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Constructing Meaning from Stokes (1864)

• What was done? Read Section 11 of the Stokes
  article. In the left-hand column of the work
  sheet, transform Stokes description into a
  multi-step protocol suitable for an undergraduate
  chemistry laboratory experiment.
• What was seen? In the middle column, describe
  what observations students would make.
• What happened chemically? In the last column,
  explain briefly in words the chemical basis for
  the observations.
• How do we represent it? On the back of the work
  sheet, construct a diagram (model) that
  represents the chemistry.

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Transforming Section 11 of Stokes Article into a
Laboratory Experiment
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Question for Group Work on Midterm Examination
Prof. Essigsaure returned to his lab one night to
prepare for a lecture demonstration based on the
experiment presented in the second paragraph of
Section 11 in Stokes 1864 article. Within
minutes he was looking high and low for the
glacial acetic acid and mumbling angrily about
associates who dont replace the things they use
up. Frustrated, but undaunted, he figured any
acid would do and substituted concentrated
hydrochloric acid. After all, he reasoned, a
stronger acid should work even better. Not so.
Sure enough the hemoglobin solution turned brown
immediately upon addition of HCl but, much to his
initial puzzlement, the resulting hematin did not
extract into the ether layer. Explain in
chemical terms why HCl cannot be substituted for
glacial acetic acid in this experiment. Draw
chemical structures and diagrams to support your
argument. If you are uncertain of the
explanation, please outline the possibilities you
have considered or how you analyzed the problem.
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Constructing Models to Explain Observations
O2 (g)
Air
1. Diffusion, slow transfer
2. Shaking, rapid transfer
Water
O2 (l)
H2O
SnII
SnIV
HbO2
Hb
Irreversible oxidation, slow
Reversible binding, rapid
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Introduction to Biochemistry Student Assignments

• Write an Abstract
• Construct a Concept Map
• Draw an Appropriate Illustration
• Critique from a Modern Perspective
• Find out about the Author
• Explore a Cited Reference

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Introduction to BiochemistryStudent Perceptions
1995-2004A. Consider items 1 through 12 and
rate them with respect to how important they are
for success in CHEM-342, Introduction to
Biochemistry. (1 Extremely Important to 5
Not Important N 263 out of 268)
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Introduction to BiochemistryStudent Perceptions
1995-2004B. Consider the items 1 through 12 in
relation to other science courses. Circle those
items which, in your experience, are more
important in CHEM-342 than in most other science
courses you have taken. (N263)
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Effect of Facilitators on Attendance
Attendance before facilitators 91.1 Attendance
after facilitators 94.1 (32 reduction in
absences)
Allen White (2001). In, Student-Assisted
Teaching, Miller, Groccia Miller, Eds. Bolton,
MA Anchor.
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Effect of Facilitators on Effort
Hours before facilitators 4.8 per week Hours
after facilitators 6.0 per week (25 increase
in time spent on course work outside of class)
Allen White (2001). In, Student-Assisted
Teaching, Miller, Groccia Miller, Eds. Bolton,
MA Anchor.
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Learning Issue Matrix
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Prelude to the Final Exam

• Always remember that it is possible to be a
  worthwhile human being regardless (or in spite
  of) how much biochemistry you know. This won't
  necessarily help you with biochemistry, but it
  may help you keep your sanity.
• Hiram F. Gilbert (1992)

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Course Web-Site

• Introduction to Biochemistry
• www.udel.edu/chem/white/CHEM342.htm