1. A Textbook and Other Resources for Teaching Challenge-Based Biotransport
Ken Diller and I were Biotransport Domain investigators on the Vanderbilt-Northwestern-Texas-Harvard/MIT Engineering Research center for Biomedical Educational Technologies. This ERC brought together Domain experts, learning scientists, technology experts and assessment experts for the purpose of extending education research originally conducted at the K-12 levels to the bioengineering curricula.
Robert J. Roselli, Vanderbilt University
Kenneth R. Diller, University of Texas, Austin

2. Student Centered Knowledge Centered Assessment Centered
Learning Environment
Community Centered
Student
Centered
Knowledge
Centered
Assessment
Centered
Vanderbilt-Northwestern-Texas-Harvard/MIT Engineering Research center for Biomedical Educational Technology. Our primary objective was to see if we could transfer education research that was originally conducted at K-12 levels to college bioengineering curricula. The K-12 research is summarized in the book “How People Learn”, often abbreviated HPL, published by the National Research Council. A key finding was that the most effective learning environments are those that not only are knowledge-based, but also involve direct student participation, afford frequent formative assessment opportunities, and are relevant to the community at large. 2

3. Multiple Perspectives
Generate Ideas
Research & Revise
Test your mettle
Go Public
The Challenge
Challenge-
Based
Instruction
(CBI)
We found we could best incorporate those principles by adoping what is known as challenge-based instruction. Students are presented with a Challenge. A legitimate challenge is a problem that has real-life relevance, but the students do not yet know how to solve it. Students Generate Ideas on their own and in small groups in the classroom, where they determine what they do and do not know about the challenge. Ideas from the groups are discussed in the classroom, providing Multiple Perspectives, with the instructor and possibly others from the community bringing in additional perspectives. By this time the students are ready for a lecture, which may be followed by reading assignments or other Research activities. These are followed by Test your Mettle, which involves in-class formative assessment via electronic poling and assessment of problems worked in class and for homework. Often the original approach turns out to be incorrect and students must make revisions – thus Research & Revise. Most of the module is spent in this activity. Ultimately, the students are able to solve the Challenge and Go Public. However, there is more to Going Public than simply solving the challenge. Go Public means that the knowledge gained by students while solving the specific challenge allows them to solve other problems that are based on the same principles. They can demonstrate this ability by solving related homework and exam problems.

4. Objections to the use of Challenge-Based Instruction by Instructors
I’m not convinced that challenge-based instruction is more effective than traditional lecture-based instruction at the college level.
I don’t have time to develop effective challenges.
I won’t be able to cover the necessary material in my course if valuable lecture time is lost to student discussions and other in-class CBI activities.
There are three primary objections to challenge-based instruction that I hear from instructors all the time. First, …
So, let’s address these one at a time. First, with respect to the effectiveness of CBI …

5. Meta-analysis of VaNTH Studies
Effect Size = (CBI mean – Traditional mean)/ (pooled SD)
Meaningful difference
Substantial difference
VaNTH conducted several studies in bioengineering classes where challenge-based modules or courses were compared with traditional modules or courses. The effect size was used to compare the two groups. Effect size equals the mean of the challenge-based group minus the mean of the traditional group divided by the pooled standard deviation. Effect sizes greater than 0.3 indicate meaningful differences while effect sizes greater than 0.8 represent substantial differences. The results indicated that there were no differences between groups in 18% of the studies, but meaningful or substantial differences were found in favor of challenge-based instruction in 82% of the studies. There were no studies where meaningful differences were found in favor of the traditional method. So we concluded in this JEE paper that challenge-based instruction is effective at the college level.
Cordray, D., Harris, T. R., Klein, S., A research synthesis of the effectiveness, replicability, and generality of the VaNTH challenge-based instructional modules in bioengineering. J. Engineering Education, 95, , 2009.

6. Biotransport Modules (Roselli)
CBI
Introduction to BME 210
Heart-lung machine
Renal vascular resistance
Hemorheology
Osmotic shock
Blood flow in circular tubes (arteries)
Blood flow in elliptical vessels (veins)
Heat transfer in mixing
Determination of time of death
Heat exchanger design
Pharmacokinetics
Determinates of cell size
Gas exchange and blood doping
Analogies
Biofluids
Bioheat
Now to the issue of developing challenge-based modules. Yes, these take considerable time and effort to develop, but once they are developed they can be used over and over. In addition, it is very easy to use modules developed by someone else. I developed this set of 13 modules for an introductory biotransport course – one that deals with the research on CBI, so students know why the course is taught as it is, one that emphasizes the analogies between momentum, heat and mass transport , 5 short modules that deal with biofluids, and three longer modules that deal respectively with bioheat and biomass transfer.
Biomass

7. Biotransport Modules (Diller)
Heart Lung Machine
Generate Ideas
Blood Doping
Mucous Transport by Cilia
Respiratory Air Flow
Post Mortem Interval
HLM #2 - Cooling During Cardiac Surgery
Coffee Burns
Domestic Hot Water Safety Standards
Space Suit Thermal Design
Membrane Diffusion
Ken Diller uses some of the same modules in his introductory course and has developed several of his own, with more emphasis on bioheat transfer and less on mass transfer.

8. Where can we find Biotransport Modules?
Powerpoint Modules
And Resources:
My modules and additional resources have been posted at vanth.org/biotransport and you are welcome to use them and modify them to your liking. Ken’s modules are not in powerpoint files, but he will be happy to share them with you. In addition, most of our challenges are included in our new textbook, Biotransport: Principles and Applications. So, the bottom line is that you don’t have to spend any time developing challenge-based modules. You can adopt and modify modules that already exist until you feel comfortable developing your own.
I have two copies of the textbook here that I will pass out so you can browse through them. There are also order forms available at the front table for those who might want to explore it further or adopt the text for their biotransport courses.
Don’t need to develop your own modules

9. How can I cover the necessary material in my course if valuable lecture time is lost to student discussions?
Now to the final objection to challenge-based instruction, “How can I cover all the material that needs to be covered if I use some class time for discussions rather than lecture? The answer is that students must get some information outside the classroom that was formerly covered in the classroom lectures. This would include outside reading assignments to obtain derivations and examples that cannot be included in lectures, and relevant homework problems can solidify what is covered in class. In short, you need a good resource that students can use outside the classroom. (click) Ken and I have designed this textbook to be such a resource.

10. Why Another Biotransport Textbook? What’s Unique?
Introduces Students to CBI.
Covers Momentum, Heat and Mass Transport and Emphasizes Analogies Between them.
Provides Detailed Derivations.
Provides Useful Challenges.
Avoids Tensor Notation.
Designed for Learning rather than Reference.
Includes Properties of Biological Materials.
Emphasizes Problem Solving Procedures.
Includes Extensive Biotransport Examples.

11. Examples
Each example in the text begins with a highlighted problem statement and follows the same solution procedure throughout, starting with initial considerations, then system definition….

12. Derivations
We have attempted to show all intermediate steps in derivations so some derivations previously made in class lectures can be safely assigned as homework. The shortest derivation in the text, a one-dimensional mass balance, is shown here. It begins with a conservation statement in words, which is highlighted. The final result is also highlighted, but the intermediate steps are not.

13. Textbook Organization
Fundamentals Of
How People Learn
Part I
Fundamental
Concepts in
Biotransport
Part II
Part III
Part IV
Part V
Biofluid
Transport
Bioheat
Transport
Biomass
Transport
The text is organized into 5 parts and a set of appendices. Part I introduces students to the fundamentals of How People Learn. Part II deals with the fundamental concepts in biotransport and the analogies between momentum, heat and mass transfer. Part III deals with biofluid transport, part IV with Bioheat transport and Part V with Biomass Transport. The Appendices include an extensive nomenclature section that contains the fundamental dimensions and SI units of all symbols used in the text and shows where that symbol first appears in the text. The appendix also includes physical constants, conversion factors, transport properties for standard and biological materials, and charts that can be used for transient conduction problems for slabs, cylinders and spheres.
Appendices
A. Nomenclature B. Physical Constants, Conversion Factors C. Transport Properties D. Charts for Transient Conduction & Diffusion

14. Part II. Fundamental Concepts
Chapter 2 Fundamental Concepts
System Definition
Transport Scales
Conservation Principles
Transport Mechanisms
Transport Coefficients
Interphase Transport
Chapter 3 Modeling & Solving Problems
Theoretical Approach
Empirical Approach

15. Parts III, IV & V Organization
First Chapter: Basics
Fundamentals
Unique Transport Features
Relevant Empirical Relationships
Boundary Conditions
Second Chapter: Macroscopic Approach
Third Chapter: 1-D Shell Balance Approach
Fourth Chapter: General Microscopic Approach

16. Chapter Organization Introduction Context-specific Concepts
Summary of Key Concepts
Questions
Problems
Challenges
References

17. Selected Biofluid Transport Topics
Blood Rheology
Vascular Resistance, Compliance & Inertance
Microvascular Blood Flow
Flow in Collapsible Vessels
Windkessel Arterial Model
Osmotic Pressure and Flow
Flow in Tapered & Permeable Vessels
Pulsatile Flow in Arteries

18. Selected Bioheat Transport Topics
Human Thermoregulation
Thermal Dilution Methods
Burn Injury
Metabolic Heat Generation
Biological Heat Exchangers
Hyperthermia
Laser Tissue Irradiation
Wind Chill

19. Selected Biomass Transfer Topics
Permeability
Cellular Transport
Gas Exchange
Enzyme Kinetics
Bioreactors
Kidney Dialysis
Pharmacokinetics
Blood Oxygenators
Electrical Charge

20. Typical Uses
The textbook can be effectively used in both traditional and challenge-based courses.
It can be used for courses in biotransport, biofluids, bioheat or biomass transport.
It can be used in introductory courses, upper division undergraduate courses, and graduate level courses.

23. Taxonomy-Based Instruction
Start with a general principle, illustrate it with specific cases
e.g., derive the Navier-Stokes Eq.,
then apply it to flow in an artery

24. Challenge-Based Instruction
Start with a specific case:
Students do not have sufficient background to adequately address the challenge on their own
Design activities that bring in relevant portions of the taxonomy
Build up to general principles

25. Part I. HPL Fundamentals

26. Appendices A. Nomenclature B1. Physical Constants
B2. Prefixes & Multipliers, SI Units
B3. Conversion Factors
C. Transport Properties
Fluid properties
Normal blood perfusion rates in tissue
Thermal properties
Mass transfer properties, solubility coefficients, partition coefficients
D. Charts for Unsteady State Conduction & Diffusion

27. Nomenclature

28. Textbook Challenges
Two bioheat transfer challenges from the text are shown here: The postmortem analysis (or determination of the time of death) and an actual lawsuit based on falsification of data from a Heart-Lung machine. So, the bottom line is you don’t have to spend any time developing challenge-based modules, you can adopt and modify modules that already exist

29. Selected Fluids Topics
General Fluid Mechanics
Biofluid Transport
Newtonian & Non-Newtonian Fluids
Conservation of Mass
Conservation of Momentum
Conservation of Energy
Engineering Bernoulli Equation
Laminar & Turbulent Flow
Friction Factors, Friction Loss
Internal & External Flow
1-D & 3-D Shell Balances
Substantial Derivatives
Stream Function
Scaling Continuity & Navier-Stokes
Solving Non-Newtonian Problems
Rheological Properties of Blood
Biorheology and Disease
Blood Flow in Microvessels
Blood Flow in Organs
Vascular Resistance, Inertance
Vascular & Lung Compliance
Windkessel Arterial Model
Flow in Collapsible Vessels
Transmembrane Flow
Osmotic Pressure and Flow
Flow in Permeable Vessels
Flow in Tapered Vessels
Pulsatile Flow in Arteries 29

30. Selected Heat Transfer Topics
General Heat Transfer
Bioheat Transport
Constitutive Relationships
Conduction
Convective Heat Transfer
Radiation Heat Transfer
Heat Generation
Thermal Resistance, Biot Number
Heat Transfer Coefficients
Phase Change
Lumped Parameter Analysis
Compartmental Analysis
Heat Exchangers
Numerical Methods
Graphical (Heisler) Solutions
Human Thermoregulation
Thermal Dilution Methods
Flame Burn Injury
Metabolic Heat Generation
Biological Heat Exchangers
Hyperthermia
Laser Tissue Irradiation
Heat Exchange in Tissue
Wind Chill Factor
Safe Touch Temperature
Fire Shelter Design
Heat Loss from Finger
Low Temp Tissue Storage 30

31. Selected Mass Transfer Topics
General Mass Transfer
Biomass Transport
Mass & Molar Concentration
Phase Equilibrium
Species Transport Between Phases
Molecular Diffusion
Fick’s Law, Single Phase
Diffusive & Convective Flow
Electrically Charged Species
Chemical Reaction
Internal & External Resistance
Species Conservation
Compartmental Analysis
Mass Transfer Coefficients
Superpositon
Membrane Permeability
Hollow fiber permeability
Cellular Transport, Charged species
Lung O2, CO2 Exchange
Tissue O2, CO2 Exchange
Enzyme Kinetics
Immobilized Enzyme Devices
Bioreactors
Kidney Dialysis
Pharmacokinetics
Blood Oxygenators
Transvascular Solute Transport 31

32. Methods: Posttest vs. Pretest
1) Knowledge Questions: 6 multiple choice
2) Open Ended Problem
Ken Diller and his colleagues conducted a study in biotransport that appeared in the Annals where student learning in four classes at three Universities was compared. Two classes were taught in the traditional lecture-based mode and two in the challenge-based mode of instruction. A test consisting of 6 knowledge-based questions and an open-ended question was given at the beginning and end of the course in each class. “Results showed …
“Results show that HPL and traditional students made equivalent knowledge gains, but that HPL students demonstrated significantly greater improvement in innovative thinking abilities.”

33. Innovation
CBI
Students in challenge-based biotransport classes showed an improvement in innovation, while students in traditional biotransport courses actually showed a decrease in innovation. The innovation score reflects …
Innovation: This score reflects how effectively students apply their knowledge base and analysis tools to devise a wise strategy for solving a difficult open ended problem.

34. Efficiency
CBI
Students in challenge-based biotransport classes showed substantial improvements in efficiency, while students in traditional biotransport courses were less efficient than at the beginning of the course. The efficiency score reflects … So, clearly, challenge-based instruction at the college level better prepares biotransport students to handle open-ended problems.
Efficiency: This score reflects the ability of students to properly model the process by applying appropriate governing principles and constitutive relations.