Postdoc Spotlight: Dr. Bhanu Sharma

Concussion management is changing as more research suggests exercise is best approach

Concussion patients were once prescribed rest in a dark room, but in recent years concussion management has literally come out of the dark. (Shutterstock)
Bhanu Sharma, McMaster University

Public interest in concussion has exploded over the space of a generation, together with a new understanding of how best to help patients recover. Concussion patients were once prescribed rest in a dark room, but in recent years concussion management has literally come out of the dark.

This is in large part because of a research boom: the number of studies on this mild form of traumatic brain injury has multiplied by 15 times over the last 20 years. This spike is a sign that the relatively young field of concussion research is maturing into a deeper science. It has created new evidence to support an entirely new approach to treating concussion. A recent wave of research papers has turned old practices on their heads.

Past approach: A dark room

For many years, concussion management followed a rest-is-best approach.

Under this passive approach, patients were advised to avoid cognitive and physical activity until their symptoms naturally resolved, leading to the notion that a dark room was the best environment for recovery.

Two soccer players colliding while trying to head a ball
The number of research papers on concussion management has increased greatly over the last 20 years, leading to new approaches to treatment. (AP Photo/Phelan M. Ebenhack)

The problem was that there was scant evidence to support the dark-room method.

The motivation for using rest as a concussion-management strategy was a desire to limit exposure to environments and activities that might lead to secondary concussions, which can have compounding, longer-lasting effects. Avoiding secondary injury was prioritized over proactive recovery.

But we are now in the midst of a transformation in concussion management.

Exercise is medicine

In the past few years, scientists have started to study aerobic exercise (or cardio training) as a management strategy for concussion symptoms. This exercise-is-medicine approach is diametrically opposed to the rest-is-best status quo.

Many studies have examined the effects of sub-maximal (low-to-moderate intensity) aerobic exercise on concussion symptoms. This research confirms the utility and safety of such exercise for managing concussion symptoms, which vary between individuals, but they are typically categorized as somatic (or physical), cognitive, emotional and sleep-related. They can be assessed using adult- and child-specific symptom scales.

A man running on a treadmill while another man wearing a lanyard observes.
Prescribing exercise in concussion typically involves a baseline test. (Shutterstock)

An academic review that summarizes the findings of individual studies shows that exercise is indeed one of the most effective, evidence-informed strategies for managing concussion symptoms. Beyond a brief period (24 to 48 hours) of rest after concussion, the science now suggests that exercise is more beneficial than rest.

Prescribing exercise in concussion typically involves a baseline test. The most widely studied tests require patients either to walk on a treadmill with the incline gradually increasing throughout the test or cycle on a stationary bicycle against progressively increasing resistance.

Patients exercise under supervision until they experience an increase in symptoms (which research shows is transient and not associated with poor long-term outcome) or are unable to continue exercising. The heart rate at the point where the test is terminated is noted, and patients are then prescribed an exercise program involving five to six days of aerobic exercise at an intensity equivalent to 80 per cent of the maximum heart rate achieved during the test.

Ongoing research

Man sitting on grass with his eyes closed and his fingertips on his temples
The motivation for using rest as a concussion-management strategy was a desire to limit exposure to environments and activities that might lead to secondary concussions. (Pexels/Kindel Media)

As a next step, scientists are hard at work trying to determine the exact mechanism by which such sub-maximal exercise improves concussion symptoms. A leading hypothesis is that the autonomic nervous system (which regulates involuntary physiological processes, such as heart rate and breathing) is disturbed following a concussion, with its two constituent sub-systems becoming “uncoupled.”

Sub-maximal aerobic exercise is thought to engage the autonomic nervous system in a way that helps restore balance to this critical command centre. Simply put, it looks like exercise can safely and effectively generate the biological change required to overcome the symptoms of concussion.

More research is needed to build on this growing base of exercise-concussion knowledge. We need to understand how different frequencies, intensities, times and types of exercise can lessen symptom burden.

Illustration of a brain on a purple and blue background
Researchers need to know how exercise impacts brain function in concussion as. (Unsplash/Fakurian Design)

Other research, including my ongoing work at McMaster University, aims to develop understanding of the effects of exercise by studying its impacts not only on symptoms, but also on brain activity. We need to know how exercise impacts brain function in concussion as, after all, concussions are brain injuries.

This shift in concussion management may mean better care will become available for patients. It is also a story about the power of bold science, the type of science which questions accepted wisdom and rebuilds first principles using evidence.

Challenging norms by changing perspective can lead to new approaches and better outcomes. Sometimes, as in the case with concussion, the game needs to be changed.The Conversation

Bhanu Sharma, Post Doctoral Fellow, Faculty of Engineering, McMaster University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Dr. Leanne Grieves and Dr. James McKendry published their first education aritcle!

Dr. Leanne Grieves and Dr. James McKendry, '21 McCall MacBain Fellows, have published a paper from their education research project with Engineering Professor Dr. Seshasai Srinivasan. 

Grieves, L. A., McKendry, J., Muhammad, N., & Srinivasan, S. (2022). The Transition from In-class to Online Lectures During a Pandemic: Understanding the Student Experience. International Journal of Engineering Education, 38(2), 376–392.

The Transition from In-class to Online Lectures During a Pandemic: Understanding the Student Experience

376–392 Leanne A. Grieves, James Mckendry, Nasim Muhammad and Seshasai Srinivasan

In light of Covid-19, McMaster University abruptly transitioned all classes to an online format in Winter 2020, with online classes continuing through the Winter 2021 term. To improve our existing technological framework for the delivery of online courses, we surveyed undergraduate students in McMaster University’s engineering program to assess their online learning preferences and their experience of the transition from in-class to strictly online learning. We identified student preferences for educational video type, number, duration and identified barriers to an online learning environment. In addition to outlining the students’ perspective, we present our findings in the context of the students’ learning by contrasting student learning in the online environment with the learning of earlier cohorts in the in-person environment (i.e., before the pandemic). We assess learning via student performance in exams and assignments for each course. After considering the student’s perspective and learning outcomes, we provide recommendations for an optimal content delivery methodology in an online learning environment.

Keywords: active learning; constructivist theory of learning; Covid-19; education; online learning

Postdoc Spotlight: Dr. Jan Pohls

A new approach finds materials that can turn waste heat into electricity

The Curiosity Mars rover, launched in November 2011, is powered by a nuclear battery that relies on thermoelectric materials to turn heat from radioactive decay into electricity. (NASA/JPL-Caltech/MSSS), CC BY-NC
Jan-Hendrik Pöhls, McMaster University

The need to transition to clean energy is apparent, urgent and inescapable. We must limit Earth’s rising temperature to within 1.5 C to avoid the worst effects of climate change — an especially daunting challenge in the face of the steadily increasing global demand for energy.

Part of the answer is using energy more efficiently. More than 72 per cent of all energy produced worldwide is lost in the form of heat. For example, the engine in a car uses only about 30 per cent of the gasoline it burns to move the car. The remainder is dissipated as heat.

Recovering even a tiny fraction of that lost energy would have a tremendous impact on climate change. Thermoelectric materials, which convert wasted heat into useful electricity, can help.

Until recently, the identification of these materials had been slow. My colleagues and I have used quantum computations — a computer-based modelling approach to predict materials’ properties — to speed up that process and identify more than 500 thermoelectric materials that could convert excess heat to electricity, and help improve energy efficiency.

Making great strides towards broad applications

The transformation of heat into electrical energy by thermoelectric materials is based on the “Seebeck effect.” In 1826, German physicist Thomas Johann Seebeck observed that exposing the ends of joined pieces of dissimilar metals to different temperatures generated a magnetic field, which was later recognized to be caused by an electric current.

Shortly after his discovery, metallic thermoelectric generators were fabricated to convert heat from gas burners into an electric current. But, as it turned out, metals exhibit only a low Seebeck effect — they are not very efficient at converting heat into electricity.

A black and white photo of a woman turning a dial on a large table top radio, with a lantern hanging above it.
The kerosene radio was designed for rural areas, and was powered by the kerosene lamp hanging above it. The flame created a temperature difference across metals to generate the electrical current. ('Popular Science', Issue 6, 1956)

In 1929, the Russian scientist Abraham Ioffe revolutionized the field of thermoelectricity. He observed that semiconductors — materials whose ability to conduct electricity falls between that of metals (like copper) and insulators (like glass) — exhibit a significantly higher Seebeck effect than metals, boosting thermoelectric efficiency 40-fold, from 0.1 per cent to four per cent.

This discovery led to the development of the first widely used thermoelectric generator, the Russian lamp — a kerosene lamp that heated a thermoelectric material to power a radio.

Are we there yet?

Today, thermoelectric applications range from energy generation in space probes to cooling devices in portable refrigerators. For example, space explorations are powered by radioisotope thermoelectric generators, converting the heat from naturally decaying plutonium into electricity. In the movie The Martian, for example, a box of plutonium saved the life of the character played by Matt Damon, by keeping him warm on Mars.

In the 2015 film, The Martian, astronaut Mark Watney (Matt Damon) digs up a buried thermoelectric generator to use the power source as a heater.

Despite this vast diversity of applications, wide-scale commercialization of thermoelectric materials is still limited by their low efficiency.

What’s holding them back? Two key factors must be considered: the conductive properties of the materials, and their ability to maintain a temperature difference, which makes it possible to generate electricity.

The best thermoelectric material would have the electronic properties of semiconductors and the poor heat conduction of glass. But this unique combination of properties is not found in naturally occurring materials. We have to engineer them.

Searching for a needle in a haystack

In the past decade, new strategies to engineer thermoelectric materials have emerged due to an enhanced understanding of their underlying physics. In a recent study in Nature Materials, researchers from Seoul National University, Aachen University and Northwestern University reported they had engineered a material called tin selenide with the highest thermoelectric performance to date, nearly twice that of 20 years ago. But it took them nearly a decade to optimize it.

To speed up the discovery process, my colleagues and I have used quantum calculations to search for new thermoelectric candidates with high efficiencies. We searched a database containing thousands of materials to look for those that would have high electronic qualities and low levels of heat conduction, based on their chemical and physical properties. These insights helped us find the best materials to synthesize and test, and calculate their thermoelectric efficiency.

We are almost at the point where thermoelectric materials can be widely applied, but first we need to develop much more efficient materials. With so many possibilities and variables, finding the way forward is like searching for a tiny needle in an enormous haystack.

Just as a metal detector can zero in on a needle in a haystack, quantum computations can accelerate the discovery of efficient thermoelectric materials. Such calculations can accurately predict electron and heat conduction (including the Seebeck effect) for thousands of materials and unveil the previously hidden and highly complex interactions between those properties, which can influence a material’s efficiency.

Large-scale applications will require themoelectric materials that are inexpensive, non-toxic and abundant. Lead and tellurium are found in today’s thermoelectric materials, but their cost and negative environmental impact make them good targets for replacement.

Quantum calculations can be applied in a way to search for specific sets of materials using parameters such as scarcity, cost and efficiency. Although those calculations can reveal optimum thermoelectric materials, synthesizing the materials with the desired properties remains a challenge.

A multi-institutional effort involving government-run laboratories and universities in the United States, Canada and Europe has revealed more than 500 previously unexplored materials with high predicted thermoelectric efficiency. My colleagues and I are currently investigating the thermoelectric performance of those materials in experiments, and have already discovered new sources of high thermoelectric efficiency.

Those initial results strongly suggest that further quantum computations can pinpoint the most efficient combinations of materials to make clean energy from wasted heat and the avert the catastrophe that looms over our planet.The Conversation

Jan-Hendrik Pöhls, McCall MacBain Postdoctoral Fellow, Department of Chemistry and Chemical Biology, McMaster University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Information Session Handout 2021

Click here to get a PDF copy of this handout

McCall MacBain Postdoctoral Fellows Teaching and Leadership Program

Applications are due August 18 at 5pm

This program supports the development of leadership and educational skills of Postdoctoral Fellows. We train Postdoctoral Fellows with evidence-based teaching methods to create better teachers, and in turn, better students.

The program consists of 3 training opportunities:

  • Bi-weekly Workshops aimed to teach essential teaching and leaderships skills
  • Bi-weekly Journal Club readings designed to supplement workshops with core papers in education cognition research
  • Monthly Invited speakers presenting on cutting-edge education research

And 4 outcomes:

  • An OpEd published in an online news source such as The Conversation
  • A partnership with a researcher on an educational research project
  • A short, TED-style talk, presented during our Appetizers for the Mind event in collaboration with the Alumni Office
  • The option to teach one module in the McCall MacBain INSPIRE course Perspectives in Science: Behind the Scenes

Sample Workshops

How and why you should write an Op/Ed (Wade Hemsworth)

This workshop will prepare Program Members for how to write an Op/Ed article on the topic of their choice. Writing an Op/Ed will help members fine-tune their communication skills by writing for a lay audience about a complex topic. Op/Eds can be published on the McCall-MacBain program website and submitted to other publication outlets (The Sil, The Spec, etc.)

How to prepare/design a presentation or lecture (Joe Kim)

In these two workshops, Joe will first describe how he plans out his lectures (before converting them to PowerPoint). He will then teach the program members how to design PowerPoint slides (including multimedia).

How to give a lecture that incorporates Education Cognition research (Faria Sana)

Faria will give some background about active learning and why it is so vital to use in the classroom, as well as practice active learning techniques in the workshop.

Email Connie Imbault (Program Manager and Research Coordinator) with any questions

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