Monday, December 12, 2011

Thoughts of my Lungs and 2-Cycles

Two things are on my mind every time I bike up Observatory Drive, the lakes-hore road that brings you directly to the UW Madison campus, "Will this ever end? and "Why are mopeds so dirty?"

As I struggle for oxygen near the peak, I recognize that breathing would be a lot easier if I weren't also inhaling carbon-monoxide and unburned exhaust gasses from the screaming mopeds that are lurching by me.

Recall that there are two types of engines we use in the everyday, modern world, 2-strokes and 4-strokes. They are alternatively referred to as 2-cycle and 4-cycle. The difference between the two is how they work inside and also, that one is cleaner than the other.

Passenger vehicles such as this have a 4-cycle engine and are comparatively cleaner than 2-cycles. 

"The big transition to four stroke engines was because of emissions," says Professor Foster, Director of Engine Research Center at UW Madison. "It was more expensive to buy that engine but less polluting by the standpoint of the gasses coming out."

Professor Foster attributes the cleaner emissions of 4-stroke engines due to simple technological innovation. He also comments that 2-strokes can be just as clean as 4-strokes, but the tradeoff is cost.

So why is there still a mixture of 2-stroke and  4-stroke engines? Mopeds generally have 2-strokes, so do many boat motors. All four-wheeled passenger vehicles use 4-strokes as a result of regulatory pressures to clean their emissions. The continued mixture exists due to power outputs and namely, 2-cycles produce more of it. They have more "bang for their buck,"  so to say, but the tradeoff is a less-efficient combustion, meaning dirtier exhaust.

For a comparison between 2-strokes and 4-strokes, check out here and here.

2-stroke engines are still commonly used today for things such as mopeds and outboard boat motors and tug-boat engines. However, outboard motors, due to increased awareness of water pollution, have also made the transition to a 4-cycle platform.

Overall, Observatory Drive will remain temporarily clogged with the unburned, blue exhaust from passing mopeds, although 4-stroke designs have also been around for some time. On the plus side however, mopeds remain as an fuel efficient mode of transportation, averaging anywhere between 50-100 mpg.

Saturday, December 10, 2011

Using Evolution as a Measure of the "Healthy" Diet

The fad of diets are seemingly just that, fads. They come and they go, but for as often as we see news clips about dieting trends, the question remains: What is the best diet for us?

It's the carbs that are bad, no wait, it's the fats, the sugars? As seen in the last post about diet, the dietary science world doesn't know exactly what constitutes the best meal, and certainly there is no one-size-fits-all kind.

One diet however, known as Paleolithic, bases its eating habits around our natural human evolution.

"One should eat only whole foods, focus on evolutionarily-raised (think grass-fed beef) animal meat and fats, and stay away from foods that are relatively new to our evolutionary history, such as dairy, grains, and legumes," wrote Derek Nedveck, BS in Biochemistry, who follows a paleolithic diet.

Nedveck added that the definition of Paleo is not subscribed to just one definition, but at the core it is based around the history of what humans ate as they lived, and evolved.

The Paleolithic diet argues against the consumption of grains due to the crops limited time in our 'evolutionary diet.
Image: Golden Sun by Antonio Quesada M

This natural layout of the diet is also based on a broader, whole foods approach.

"One of the other main ways of thinking about human nutrition is “nutritionism,” which is a focus on the individual parts of foods, and how they contribute to human health. From nutritionism we get fiber, omega-3, vitamin and mineral enriched foods, with the thought being that single components of a food can be added to others to achieve the same benefit, wrote Nedveck. "Paleo on the other hand values whole foods, partly due to the fact that we don't know everything that happens when we eat a food, and how the fiber in a sweet potato is digested in the presence of all the other things that make up the sweet potato. Moral of the story, nutritionism is reductionist, and paleo is more holistic."

Determining the ideal diet is difficult. To get an appreciable scientific answer would require long-term tests with a large sample group of people. A diet can be just one factor attributing to the overall health of a person, making the health effects of foods difficult to determine.

However, as for practical advice about diets, Nedveck comments "Try it out for a week, or better yet a month, and see how you feel."

Tuesday, December 6, 2011

The World's Most Studied Lake

To learn about the world's most studied Lake, check out the video below:

According to emeritus Professor J. Magnuson of the UW Limnology department, Lake Mendota has historical research data going as far back as 1850. A snapshot of this history can be found here.

View Lake Mendota Research Madison, WI in a larger map
All images, audio and video done by Eric Verbeten, with the exception of those labeled otherwise