Tag Archives: Explanation

Raising Interest in Science

An article was published last month on artofthestem.com that was titled “Five Reasons Why Your Child Won’t Be a Scientist.”  As a science nerd myself and someone always interested in raising excitement about science (hence this blog), I thought it would be useful to reflect on the reasons given in this article (which by the way, I agree with wholeheartedly).

The article begins by talking about the decrease in interest in STEM subjects (science, technology, engineering and math).  Recent research has found that students are  uninterested in STEM subjects despite the increase in STEM jobs available.

So why don’t students like science?  What makes them turn away from science and other STEM topics?  And why do some of us actually enjoy learning about science?  The article proposes five reasons that children find it hard to get excited about science.  I’ll add my thoughts to each of their reasons.

1. We have instilled the phrase “I’m not good at math or science” into a new generation.

As the article goes on to explain after its first point, many students who do study science grow up in a household where science discussion is prevalent.  This is, in fact, the case for me.  My father is a chemist, and I remember seeing his science books and articles all around the house.  I’m positive that knowing he would have an answer to a science question took the fear out of science for me.  I always had an in-house expert to go to in case of confusion.

So what if kids don’t have an in-house scientist?  I think it’s important, then, for parents to be willing to learn science with their kids as the article suggests.  This was the case for me with my mother.  While she didn’t have a science background, she was always willing to make a baking soda volcano, look up a topic in our encyclopedia with me or come cheer me on at the science fair.  Between my dad’s knowledge and my mom’s support and encouragement, science was never a scary topic for me.

2. Science is taught in a way that is opposite to what it truly is.

This statement, while sad, is usually very true.  Throughout science classes, students are taught to memorize and write down everything the teacher is saying so that they can later memorize it.  This creates an environment in which students learn what they have to learn and then probably forget it once they are tested on it.  Not only does this not encourage scientific learning, but it also doesn’t allow students to practice the scientific process.  Where is the questioning?  Where is the formation of a hypothesis? Where is the testing of a hypothesis?  So little of true science exploration is memorization.  Instead, let kids experiment and learn through that experimentation.

3. Science has lost the “cool factor” and kids have no “science heroes.”

When I was growing up, I thought Bill Nye the Science Guy was one of the greatest shows on television.  He was funny and he knew stuff!  Even in the song that opened his show he said, “Science is cool.”  So why don’t kids think it is?  With so much emphasis on rock stars and celebrities, scientists get lost in the shuffle.  We have to make it a point to explain how cool scientists are – after all, without scientists we wouldn’t have mp3 players, vaccines or even pasteurized milk.  Maybe kids need a reminder of how many cool things scientists have in fact created!

4. We don’t focus on current issues in the discipline.

The world of science, especially today, is changing at an incredibly high speed.  New discoveries and improvements on those discoveries are published every day.  Yet students are reading about science out of the same textbooks year after year.  It students can’t see science as new and changing, why would they want to study it?  Let’s focus on new findings and recent discoveries that actually affect the students and the world around them!

5. Good grades in science will not make you a scientist.

I know about this point firsthand.  Throughout high school, and even college, I did decently well in my science classes.  However, the rote memorization that allowed me to do well on science exams did little to help me at the bench as I did scientific research.  The amount of creative thinking and troubleshooting required at a science bench is not taught in science classes.  Nor is the ability to work with others toward a common discovery or the need to ask endless questions and form countless hypotheses.  These are the talents that allow scientists to succeed, yet they are not taught in classes.  If they had been, I might still be working at the bench.  I, however, much prefer reading and writing about science to actually doing it, so as a science research dropout maybe you shouldn’t listen to me anyway!

Regardless of my meandering thoughts on the topic, the truth is that we need to get kids interested in STEM topics again.  We need to encourage the next Einstein sitting in a science class right now and wondering when recess is.


VHS – Hemorrhagic Fish in the Great Lakes

In the process of completing a class project, I recently came upon the topic of viral hemorrhagic septicemia, or VHS, and I decided to do some research.  VHS is a viral fish disease that can cause large fish kills.  It is a rhabdovirus, a group of viruses that includes other disease-causing agents in fish.  “Rhabdo” means rod and refers to the shape of the virus.  There are a number of different types of the VHS virus.  The type found in the Great Lakes is nearly identical to the type isolated from the Maritime Region of Canada.

VHS virus

VHS is not a human pathogen and dies quickly at human body temperature.  However, the virus can cause large fish kills and change the dynamics of fisheries.  In Denmark, the disease caused deaths in rainbow trout farms leading to losses near $60 million US dollars annually in the early 1990s.

Fish kill

Large fish kills have also been seen in the Great Lakes region.  In 2006, fish mortalities were seen in several lakes throughout the region.  In 2008, round goby fish kills were seen in western Lake Michigan, and earlier this year a fish kill of thousands of gizzard shad was documented in the Milwaukee Harbor ship canals.

Once fish have been infected, deaths can occur days to weeks later.  It is important to note that some fish are able to fight off the disease.  Fish that are affected show hemorrhaging in the skin or near the eyes creating red patches.  Inside the fish, organs such as the liver, spleen and intestines are often filled with hemorrhages.  The ultimate cause of death is usually organ failure.

Hemorrhagic fish

VHS is transmitted between fish by exposure to bodily fluids or eating infected prey.  It also may enter the fish’s body through the gills or through open wounds.  VHS can also live outside of a fish in the water if conditions are right.  The most likely ways in which VHS is spread throughout waters are through the movement of fish (natural or by humans) and the movement of infected water in ballasts of shipping vessels or live wells of fishing boats.  Because the virus does not survive in birds and mammals, animals that eat infected fish are not likely to spread the disease.

It is not well known how or when the virus arrived in the Great Lakes region.  A likely explanation is that ballast water discharge from shipping vessels brought the virus to the lakes.  There are currently no effective treatments to stop fish to fish transmission of the disease or to treat infected fish.  Therefore, it is important that fishing and boating industries as well as recreational boaters and fishermen take precautions to avoid further spread of the virus.  With continued research and prevention steps, the virus will hopefully be stopped, fish kills will decrease, and we can all enjoy the beauty and the fish of the Great Lakes region for years to come.

Fishing on Lake Michigan

For more information about VHS, visit the Wisconsin DNR website or other DNR sites.

How Fireflies Help Us Understand Cancer

I’m back with the promised follow-up to the firefly post.  But before I get to fireflies and luciferase, I have to start with cancer cells and metabolism.  So how are fireflies and cancer cells related?  I promise it will all come together in the end.

Normal cells in our bodies respond to signals around them to decide whether to grow or not.  The signals that the cells respond to are called growth factors.  Cells will take up food and nutrients from their environment only when instructed to do so by the growth factors.  In this way, excess growth and cell division is avoided.

Cancer cells, however, are able to ignore these signals and grow uncontrolled due to mutations in their genes.  These mutations can lead to abnormal uptake of food that then leads to cancer cell growth.

In 1924, Otto Warburg observed that cancer cells take up glucose, a main food source, differently than normal cells.  In addition to taking up an abundance of glucose, cancer cells turned the glucose into lactate.  While normal cells can do this, they do so when oxygen levels are low.  Warburg found that cancer cells, however, convert glucose to lactate even when there is plenty of oxygen – a process called aerobic glycolysis.  This altered metabolism seen in cancer cells became known as “the Warburg effect.”

Tumor cells produce lactate even when oxygen is present

While the underlying cause of the Warburg effect is still being studied, the altered metabolism has been utilized for tumor imaging.  Glucose labeled with a marker can be visualized with a PET (positron emission tomography) scan, a common imaging procedure.  Because cancer cells take up more glucose than normal cells, the labeled glucose will be most abundant in cancer cells, highlighting these cells in the resulting PET image.  In this way, doctors can pinpoint areas of tumor cells.

Tumor visualized by PET scan

In a recent paper from Radiotherapy and Oncology, researchers from Switzerland looked further into the altered metabolism of cancer cells.  They aimed to observe changes in cancer cell metabolism upon treatment of the tumor with common therapies.

So, what does this have to do with fireflies?  We’re getting there.

Using tumors harvested from mice, the researchers made very thin slices of the tumor tissue.  They then measured levels of metabolites, glucose and lactate, in the slices using specific assays – bioluminescent assays.  Through an enzymatic reaction, the metabolites in the tumor slices were turned into light so that the amount of light produced indicated the amount of metabolite present in the tumor tissue.

The enzyme that catalyzed these light-producing reactions?  Luciferase, of course!

After measuring the amount of light produced from each tumor slice using a high-tech camera, the scientists could compare the levels of metabolites in different tumors.  They found that tumors that were treated with cancer therapeutics (called patupilone and IR) had lower levels of lactate and higher levels of glucose as compared to untreated tumors.  Decreased lactate levels suggested that less glucose was being converted to lactate.  Likewise, increased glucose in the tumor slice suggested that less glucose was being consumed by the cells (and, in turn, made into lactate).  In short, the altered metabolite levels in the treated tumors suggested that those cancer cells were reverting back to a more normal metabolism.

Modified from original manuscript

The measurement of altered metabolite levels in tumor slices upon treatment could be extremely useful in the therapeutics field.  By monitoring changes in cell metabolism in tumors, doctors could predict early in treatment if a therapy was going to be beneficial for a patient.  Active monitoring of cancer cell responses to a given therapy could greatly improve cancer patients’ treatment courses.

I think the firefly would be proud to know that its enzyme is working to improve the health of cancer patients, don’t you?

Proud firefly?

Fireflies and Science – An Enlightening Combination

Because they seem unusually abundant this summer (and in anticipation of an upcoming post), I thought I’d talk about fireflies today – fireflies and their role in scientific research.


 There are over 2,000 species of fireflies, and they are named such due to the bioluminescence they produce to attract mates and deter predators.  The bioluminescent reaction is clearly seen on a hot summer night, especially in tropical and temperate climates.  Many people have fond memories of catching fireflies as children, gathering them in a jar with holes poked in the lid and enjoying the soft glow – a bioluminescent nightlight.

Firefly in jar (Sounds like the title of an ode)

 So what is bioluminescence?  Bioluminescence is the production of light by a living thing (bios = living, lumen = light).  This type of luminescence is a natural example of chemiluminescence – energy released as light through a chemical reaction.  It is seen in a variety of organisms including anglerfish, fungi and glowworm beetles (which are distinct from the firefly larvae that are also sometimes called glowworms).

While, as kids, we loved the blinking lights of the fireflies, few of us probably understood how the yellow-green glow was actually created.  It is indeed a chemical reaction.

Fireflies produce two compounds that make their light show possible.  One is called luciferin and the other is luciferase.  Luciferin is a pigment that reacts with oxygen to create the light we see.  Luciferase is a catalyst in this reaction meaning that it speeds up the reaction without being used up itself.  Other components within the firefly including magnesium and ATP, an energy source, fuel the reaction.

The energy resulting from the chemical reaction is released as heatless green, yellow, or reddish light (wavelengths between 510 to 670 nanometers for the light spectrum enthusiasts out there).

Light spectrum

It is this light that we see twinkling around us on hot summer nights.  In fact, scientists think the fireflies can control the pattern and speed of “twinkling” by controlling how much oxygen (a component of the reaction) they have in their bodies.

So what does this have to with scientists and research?  It turns out that the luciferase produced by fireflies can be a powerful research tool.  Organisms can be made to glow by engineering them to express the luciferase gene.  The plant below expresses luciferase, and when watered with a luciferin-containing mixture, it glows brightly.

Glowing tobacco plant

 Probably the most common use of luciferase in labs, and one that I found helpful in my own research, is as a reporter for what is happening within the DNA of a cell.  The luciferase gene can be engineered into a cell so that it is expressed only when a specific promoter – a segment of DNA that drives gene expression – is active.

So, if I wanted to know if a chosen promoter was active, I would create a stretch of DNA in which my promoter in question would lead to creation of luciferase when active.  Then, by adding luciferin to the mix, the presence or absence of light would tell me if luciferase was expressed and if my promoter was active.

Active promoter –> luciferase expression + luciferin = light (as in a firefly)

Inactive promoter –> no luciferase expression + luciferin = no light

Using this “equation” then, scientists can determine if a stretch of DNA is active merely my measuring whether light is produced.  This is one way in which firefly luciferase helps scientists do their work.

So the next time you catch a firefly, thank it for its contribution to science.  And then let it go so it can scare away predators, attract a mate and entertain kids of all ages with its bioluminescent backside.

A glowing backside

Eating Insects – A Sustainable Food Plan?

During a recent marathon of Andrew Zimmern’s “Bizarre Foods” episodes, I found myself intrigued by his oft-repeated claim that insects could be our answer to a world-wide food shortage and the expensive practice of raising livestock.

Of course, this claim often comes as Zimmern is biting into a scorpion, tarantula, or other nightmare-inducing organism, thus causing a cringe and not much further thought on the subject.

Zimmern and an insect feast.

However, for some reason, during this recent viewing of “Bizarre Foods,” I found myself intrigued by the idea.  So I did some searching to find out just how common this idea is to those “in the know.”  Turns out insects as food is a widely discussed option that could solve an ever-growing problem.

The costs of using livestock – chickens, cows, pigs – as major food sources are huge, both environmentally and economically.  And the use of large animals is wasteful.

Insects are a different story, though.

Insects are easy to raise requiring small amounts of water, food, and space.  Additionally, they are nutritious.  For example, catepillars are full of protein, zinc, calcium, and other vitamins.  The nutritional value of insects, while often overlooked in the US, is known and utilized throughout other parts of the world.

Therefore, due to the low cost and sustainability of insects as a food source as well as their potential to provide nutrition for people with little access to other vitamin- and protein-rich foods, the possibility of insects as a solution to world food shortages holds great promise.

Now if only those unaccustomed to eating the “pests” we usually try shooing out the door could get comfortable with the idea.  If it’s up to people like Zimmern and David Gracer, who works to convince chefs and “foodies” that insects are next big thing, perhaps the bug revolution will be here sooner rather than later.

Maybe we all just need to take a cue from Timon and Pumba of “Lion King” lore and enjoy the grubs.  Timon may be right – maybe they do taste like chicken!

Timon enjoying his insect delicacies.




Revisiting a Science Hoax

As I perused the Science website the other day, I ran across another “Experimental Error” post.  For those unfamiliar with these articles, they are expertly and hilariously written by Adam Ruben.  Ruben is a scientist and the author of “Surviving Your Stupid, Stupid Decision to Go to Grad School.”

In this post for “Experimental Error,” Ruben touches upon one of the most famous scientific hoaxes perpetuated across the internet – the dangers of dihydrogen monoxide, or DHMO.

Entire websites, such as DHMO.org, are dedicated to communicating the dangers of this compound.  As the website describes, DHMO is a main component in acid rain, used in warfare, and found in many types of tumors.

Now all this is true.  But take a moment to return to your high school chemistry class and write out the formula of dihydrogen monoxide – two hydrogens and one oxygen.  H2O – water.

Due to the ease of spreading information across the Internet, the DHMO hoax has been widely heard.  A YouTube search turns up numerous “public service announcement” about the dangers of DHMO.  Countless graduate students have gathered around a lab computer to laugh about the (true) descriptions of DHMO and the inaccurate claim of its danger and our impending doom.

Some people, however, don’t think it’s so funny.  In 2004, a radio station in the town of Bremerton, WA announced that DHMO was found in the city’s water supply.  Residents of the town inundated emergency phone lines with worried questions, and the town mounted an emergency response.  Clearly, the joke had not been understood by everyone.

So, how careful do those who understand the humor behind the hoax have to be when communicating it to those who may not understand?  Are science hoaxes funny fodder for grad students during down times in the lab or potential for misunderstanding and fear?


A New Breed of Pet

Specific puppy hybrids are high-cost designer pets.  Puggles and labradoodles are carefully bred to create desired characteristics such as less shedding or more docile personalities.

But research on a new breed may change the way people think about pets.  The new designer pet?  Foxes.

Research at the Institute of Cytology and Genetics in Siberia is breeding foxes to have the same docile characteristics as our favorite lapdogs.  This is the latest version of animals being bred for domestication.  The goal at that outset of the project, over 50 years ago, was to recreate the domestication of wolves into dogs.

With each generation of fox pups, researchers tested the responses of the foxes to humans – are they approachable, can they be pet, do they wag their tails?  Amazingly, instead of taking thousands of years, it took only a few years.

Just the second generation was approachable, the fourth generation allowed themselves to be pet, and by the sixth generation, the kits followed humans around and licked them – actions practically indistinguishable from that of pet dogs.

Even more interestingly than the domestication (at least to this biologist) were the physical changes that accompanied it.  Within 15 generations of the specially bred foxes, they acquired floppy ears, spotted coats, and curly and shorter tails.  These characteristics (called a domestication phenotype) are seen in many species of domesticated animals including dogs, pigs, and chickens.

These changes seen in many domesticated animals suggest that there is a set of genes that are shared by all animals capable of domestication.  The researchers in Siberia are currently searching for those genes.  However, the genes responsible for tameness are proving difficult to find.

And how do the genes affect docility and domestication?  No one knows yet, but one theory is that the genes control chemical signals in the brain that affect attitude.  These chemical changes may then have downstream effects on the physical appearance of the animals.

So, do you want a tame fox?  A company in Siberia will sell you one.  For the low, low price of just $6, 950 (transportation and paperwork included).  The youngest that foxes can be adoped is 3 ½ months old.  And I have to admit, they’re pretty cute…

 A domesticated fox pup

The company claims that caring for the foxes is much like caring for dogs.  They can live inside or outside and can benefit from having a crate.  They can eat dog food and can even be trained to use a litter box.  They should be walked and brushed regularly.

And apparently they’re rather playful.

So, if you’re up for it, you have $7,000 lying around, and you need something a little more interesting than a plain old dog, look into getting your very own pet fox!  Oh, and as for that genetic research – maybe it’ll lead us to the next domesticated pet.  Any bets on what it’ll be?

For more information, see the recent article in National Geographic, March 2011.  Want to buy your own fox?  Visit http://www.sibfox.com/