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May 8, 2012

Posted by srstone in Biology, Evolution, Genetics, Health, Medicine, Science Education.
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Viruses: Friend or Foe?

What is invisible to the naked eye, can affect the Earth’s climate, has a tiny shell, and can causes cancer?  Viruses are considered non-living, but play a major role in our bodies and environment.  In fact, viruses kill half of the bacteria in the ocean every day.  To get an idea of how much bacteria that is, a teaspoon of water contains approximately a billion bacteria.  Recent estimates show there are 1031 viruses on this earth.  That reads, 10 billion trillion, trillion.  Although viruses are smaller than what the unaided eye is capable of viewing, if all viruses were stacked end to end, they would be lined up for about 100 million light years.

How Viruses Work

 

Viruses are constantly on the attack from the outside of our body desperately trying to get in, but 4 trillion viruses also reside inside our body.  While some viruses are trying to find a host cell and cause harm, many viruses are necessary for a healthy life.  Some of the viruses inside of us can protect us from detrimental bacteria, but can also help balance the population of bacteria vital to our health.  A similar phenomenon occurs in the ocean.  Without viruses consuming half of the bacteria day in and day out, the levels of bacteria in the ecosystem could hamper the living of certain species.  Also, bacteria contain carbon and lots of nutrients.  With the viruses consuming the bacteria, there is a constant recycling throughout the ocean.  There is a hypothesis that because of all the carbon that’s coming out, it could be affecting the Earth’s climate.  Any of the carbon that is sent back to the atmosphere is going to trap heat (greenhouse effect).  It may be an extreme thought, but these tiny, non-living viruses are partially responsible for the weather.

Bacteriophages: the lifeless killers

Viruses that attack and dispose of bacteria are known as bacteriophagesFelix d’Herelle discovered the extraordinary conclusion that viruses can kill bacteria through treating a dish of bacteria with fluid from patients with dysentery!  He actually began a business selling viruses that could cure bacterial infections.  Hypothetically, there are viruses that exist in nature that can kill the most severe bacterial infections, but it’s a matter of discovering the right viruses.  Each species of bacteria has a series of bacteriophages that can eliminate it.

Antibiotics and Viruses: An evolutionary arms race

Before antibiotics were discovered in the 1930s, a method called phage therapywas used to combat infections.  However, once these antibiotic “magic pills” were discovered, phage therapy stood in the distance.  The chemicals were reliable and scientists knew how to make them.  However, with the current widening spread of antibiotic resistance caused by bacteria developing resistance to modern medicine’s most well-used antibiotics, it’s beginning to look like phage therapy wouldn’t be a terrible idea.  One main argument phage therapy new found interest: antibiotics can’t evolve, while viruses can.  Scientists have reached the point where viruses can be engineered and genes can be strategically placed to enhance their effectiveness.  This genetic and evolutionary tinkering could allow scientists to develop viruses to strategically kill various bacteria that might be antibiotic resistant.

Genetic Engineering of Viruses

 

Viruses: Directors of Their Own Fate?

In the wake of the recent deadly avian flu virus, critics have questioned whether the spreading from mammal to mammal could have occurred on its own.  A study completed at MSU by Justin Meyer was started with the thought that it would be a wild goose chase.  Meyer wondered if lambda phages could evolve another way a new way to enter its host.

lambda was used to infect the gut bacterium E. coli.  It is harmless to humans.  The most common means for lambda to get into a cell is by attaching to its outer membrane.  The genes and proteins contained by the lambda are then injected into the microbe.  Meyer used E. coli that didn’t make the molecules necessary for the virus to grab onto.  This meant that the only viruses that would survive were ones that mutated to use a different surface molecule.  Shockingly, within 15 days, Meyer’s experiment showed that viruses were using a new channel in E. coli known as OmpF.

Meyer re-conducted the experiment with 96 lines of the virus and E. coli.  Of those 96, 24 of the lines began to use OmpF as the pathway into the host.  Because of the repeating phenomenon, the genomes of the evolved viruses were sequenced, finding that four mutations were required for the viruses to thrive.  All four were required, not a single one, or even three out of the four.  Meyer estimated the chance of all four mutations arising at once was nearly impossible: one in a thousand, trillion, trillion. However, the lambda viruses evolved to contain all four mutations in a couple weeks on a regular basis.

As incredible as this experiment is, it is somewhat frightening.  Meyer showed how easily viruses can evolve completely new traits, which can lead to new diseases.  This is exactly the reason why when treating a sickness with antibiotics, the patient MUST finish taking the dosage until it is gone, otherwise the virus can come back even stronger.

 

 

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April 5, 2011

Posted by Dr. O in Biology, Ecology, Environment/Conservation, Institute for Green & Sustainable Science (IGSS), Marian University curriculum, Physiology, Science Education.
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Congrats to Marian University’s very own, Cassie Freestone! Check out her spread (click on picture to expand) in the Spring 2011 issue of Marian University’s magazine, The Magnet.

 

Cassie Freestone has participated in numerous independent research endeavors at Marian University from a rigorous summer research course at the Institute for Green & Sustainable Science, to taking independent research credits. Her research experience has given her the toolkit to attract and succeed in internship opportunities like this international marine research study.

 

 


The PCR song April 29, 2010

Posted by Dr. O in Biology, Fun, Genetics, Science & Culture, Science Education.
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To build on the post containing the rap song on photosynthesis, I thought I’d add this little music video montage put out by Bio-Rad. It’s hilarious.  See…scientists DO have a sense of humor.

Here is the original Bio-Rad link.

Potential assignment for the new Ecological Physiology class April 27, 2010

Posted by Dr. O in Behavior, Biology, Fun, Neuroscience, Physiology, Science Education.
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MU Science Students as possible Guest Bloggers?

What do you think?  Perhaps my students should star as “guest writers” to this blog , the Animal Review, who’s blog owners “grade” animals based on their wacky adaptations.  Seems a perfect way to celebrate the diversity of physiology in the animal world.  I might just use this as an assignment for Physiological Ecology-BIO 305 in the Spring of 2012

Who needs a brain? (this coming from a neuroscientist…)

After checking out the Animal Review, I for one would have given the jellyfish a “B” and the comb jellies (Ctenophora) an “A+” for living in a “society” and incorporating “tool use” with out a true brain.

The beautiful comb jelly

I would also give the angler fish a solid B+ or A-.  The ladies are okay in their own skin and definitely wear the pants in the relationship.  After all… males are basically no better than parasites.

Let science explain how close the Butler:Duke game was April 8, 2010

Posted by Dr. O in Exercise, Fun, Physics, Science & Culture, Science Education, Uncategorized.
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In case you haven’t heard…America’s current darling (and Marian’s neighboring campus), Butler University, made a major run in this year’s NCAA Basketball Tournament.  This small Midwest liberal arts school spends $370,000 on their basketball team.   Butler’s competitor in the final, Duke, spends $370,000 PER PLAYER!

Butler lost by two points.  Gordon Hayward, who also happens to be a science major at Butler, almost won the game with a long shot at half court.  How close was it? Let science explain…

Butler University student Gordon Hayward is a science major

Marian Travels to Pensacola April 5, 2010

Posted by Colleen in Biology, Ecology, Environment/Conservation, Marian University curriculum, Science Education.
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Spring Break….and SCIENCE!

Over Marian University’s spring break, the MU Marine Biology class that I am enrolled in took a field trip to Pensacola, Florida. It’s been kind of difficult learning about marine topics while in a classroom in the middle of Indiana…the nearest ocean is hours away. Because of this, I found our Pensacola trip to be vital to my understanding of the topics we’ve covered so far this semester.

Day one

Our group began our caravan to Florida at 5 AM the Saturday of spring break and arrived to our rented beach house in Pensacola about 12 and a half hours later. As soon as we got there, the whole class ran to the beach across the street, and our learning began!

A jelly fish washed up on the beach, so of course we took pictures.

Day two

The following day, we went to Big Lagoon State Park. One of the first things we did in every new place we went to was to check water temperature and salinity. Here, the water was an icy 15 degrees C and had a salinity of 17 ppt. The water here was somewhat less salty because we were looking at an area that acted as a nursery ground to many young marine organisms. To look at these organisms, some of us took a seining net and walked through the water. Some of the organisms we found included snapping shrimp, jellyfish (one was a moon jelly), juvenile sea trout, croaker and mullet, pipefish (related to seahorses), as well as other juvenile organisms.We also looked at the primary producers in this area. Sea grass and eel grass were the plants we saw in the water and Juncus was a terrestrial plant we saw all over.

Seine nets

Day three

The following day, we took a day trip to Mobile, Alabama to look at the mud flats there. Unfortunately, the Gulf coast only experiences one tide circuit per day (compared to 2 on other oceans).   Low tide had occurred at 5:30 in the morning, but we got there around 11 AM. We did what we could as far as looking at soil samples, but information was difficult to gather here. The temperature of the water was half a degree cooler (14.5 degrees) in Mobile Bay and salinity was 10 ppt. The salinity here was so much lower because of the fresh-water river that flowed into the area.

In Pensacola Bay, right behind the house where we stayed, we looked at fouling communities, which are the communities of barnacles, and oysters that attach to buoys, boats, pilings of piers, and any other surface that they can find to claim as home. The zonation depends on how much time the object spends in or out of the water. Oysters tend to live on things that spend all or most of their time submerged. Barnacles can be higher up and can survive for periods of time out of the water.

Critters!

The beach by our house

One of the final marine aspects our class explored was to look at the water and beach of the Gulf of Mexico right outside of the house we stayed in. We took measurements of the length of the beach (from waterline to area where plant growth began) so that future classes could come down and compare our data with theirs. The water here had a much higher salinity than anywhere else we had tested at 37 ppt. The temperature was the same as most other places we tested (15 degrees). There were some interesting organisms that we came across here as well. One was the ghost crab. If you see the holes that are along the beach, that is most likely the home of one of these creatures. They range in size from very small to about the size of a fist (if you include its legs). We found a large female crab and brought her in to study, but she must have been old because she died the next day. We also tried bringing in a smaller one we found later on in the week, but there was an accident and the little guy got crushed. A third and fourth were brought back to our house and placed in a tank. On was large and the other was small. Unfortunately for the smaller crab, the big guy got hungry. Before we came home again, we let go our lone surviving crab. I’m sure she was glad to be free again.

How to talk to a climate change skeptic April 1, 2010

Posted by Dr. O in Climate Change, Environment/Conservation, Policy, Science & Culture, Science Education.
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A lot of students have asked me how to effectively and intelligently communicate with a climate change/human-induced global warming skeptic.

I realize that I have been at this science career thing longer than most of you students so in a way, yes, it is easier for me to “argue” on a different level over a variety of scientific results.  As a scientist, it’s our job to think critically, analyze effectively, and yes…be skeptical.  But we must also be balanced AND properly interpret the data. Hopefully ALL those papers I make you write and ALL that literature I make you read is helping YOU to also think critically and interpret science effectively.

But everyone can use a cheat sheet now and then…

Our local Hoosier Environmental Council put out a neat link to an article which has a “point and click” menu of points on which one can educate themselves on the main arguments climate change skeptics use…and why their arguments don’t stand up scientifically.

Check it out.

Educate yourselves about your local Indy environment March 29, 2010

Posted by Dr. O in Environment/Conservation, Health, Science & Culture, Science Education.
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Earth Day is coming up.  April 22nd to be exact. While we will likely focus most of our attention on global climate change, fossil fuel use, and habitat destruction, I do think it is paramount to educate one’s self about the environmental pitfalls within your local community.  The USA is a known culprit of spewing a major portion of the world’s air pollution.  The Midwest produces the majority of the nation’s pollution.  Indiana produces the most pollution in the Midwest.

While we should rightly so be worried about what this air pollution is doing…or undoing…for the Earth’s climatic balance…we should also be very worried about what this air pollution is doing to our local Indy communities.  And by local, I mean neighborhood by neighborhood.  Indianapolis is a heavily industrialized city with very little environmental oversight.  This lack of oversight has led to markedly increased disease among Indy residents.  A recent article in the Indy Star highlights some of the most disturbing facts, focusing on low-income neighborhoods in the city’s Southwest side.

Here are a few jaw-dropping statistics:

• In one of those [neighborhood] tracts, 15 of 100 deaths were attributed to lung cancer — 95 percent higher than the county rate.

• Residents of that tract were hospitalized for respiratory problems at rates more than three times the county average in 1998 and 1999.

State and local environmental and health officials have done almost nothing to investigate documented risks from air pollution or the health problems they may cause.

Here is a link to the article. So while you celebrate Earth Day and commit to making changes in order to ameliorate changes made to our fragile global ecosystem…make sure you start at home.  Educate yourself and then find out how you can take action.

Welcome! January 21, 2010

Posted by Dr. O in Biology, Chemistry, Math, Physics, Science Education.
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Welcome to the Marian University, School of Mathematics & Science’s MU SCIENCE BLOG!

This blog is powered by Marian University science students including those majoring or minoring in biology, chemistry, math, or physics.

Please check out what the students have to say and ENJOY!