Wednesday, July 28, 2010

Data Interpretation in the Gulf

Reports out of the Gulf of Mexico come at us every day: the status of the well head closure, wildlife death counts, weather effects. Many of these reports conflict. As we start day 100 of the BP leak, we're still not sure how much oil has actually passed from the underground reservoir into the aquatic ecosystem, or how much wildlife has been killed. The government reports one estimate; independent researchers another. And the reports now being issued on dissolved oxygen concentrations in the water in the Gulf show another series of discrepancies.

To the average person, much like the conflicting arguments on climate change, this can be very confusing and frustrating. Why aren't the scientists on both sides of the fence coming up with the same conclusions? After all, they're sampling the same waters! How is it, for example, that researchers from the University of California at Santa Barbara or University of Georgia at Athens can state with confidence that oxygen levels in parts of the Gulf have dropped 30% to 50% since the leak began, but government researchers claim the changes are minimal?

The answer lies in a combination of Research Methods and Data Interpretation. Dissolved oxygen (the oxygen aquatic animals rely on to breathe) is measured through the use of specialized equipment that can detect the concentrations in the water at parts per million. This equipment typically has a sensitive membrane that allows oxygen to pass through. Unfortunately, much like the gills on a fish, this membrane is sensitive to the clogging nature of oil. So, while independent researchers are confident that their equipment is functioning properly, doubt is still cast on the reliability of their data. To confound this, other researchers have used different methods of calculation (such as Winkler titrations) and are coming up with different results.

Complicating matters further, not all of the researchers are sampling in the same areas. Many independent researchers argue that the data suggesting low oxygen changes is coming from areas close to the well head where the population of oil-consuming organisms have not increased. (The reduction of oxygen is the result of a bloom in these populations, much like a seasonal algal bloom in a lake.)

Even if all of the data did come out similar, though, there would still be much to argue about. An event of this magnitude is, fortunately, something that we don't encounter often, which means that the long-term effects are hard to determine for certain. Scientists in the Gulf have been using modeling techniques based on knowledge from smaller spills to make educated guesses, but every ecosystem is different. The currents, weather patterns, and wildlife of the Gulf of Mexico, for example, is very different from that of Prince William Sound, Alaska.

As the clean-up efforts and monitoring continue (and they likely will for years), it's important to remind ourselves that science is not a series of facts that are determined simply, but a process of discovery that includes a significant element of human influence and input from multiple sources. Only time will tell what the realities of the situation are. In the meantime, it's important for as much reliable information to be gathered as possible to add to the repository of data.

Do you deal with research methods or data interpretation in your classroom or work? What do you think of the discrepancies scientists in the Gulf are showing? How would you explain this to a non-scientist?

Monday, July 26, 2010

What Did We Do Before Google?

We've all had the thought on occasion. How, exactly, did we function before Google? (Some of us even marvel at how much we were able to accomplish before the internet.) And it seems that this ubiquitous entity has once again shown how useful it can be -- this time in the realm of astronomy and earth science research.

Researchers have been using the image database of Google Earth as a new information source for finding incidences of meteorite impact...and in August of 2008 found a fairly recent one in southwestern Egypt. The 45-meter-wide crater was likely caused in the last few thousand years by a fast moving iron meteorite and in all likelihood was witnessed by ancient Egyptian civilization. The spoke-like rays of soil from the impact have seemingly remained intact -- or, at least, enough so that were visible through Google's satellite images. Further research has shown that the crater appears in satellite images in the early 1970s.

You can see the team's Materials and Methods online, or read the full paper in the July 22, 2010 issue of Science. To view the crater on Google Earth, the coordinates are 26º05′15″E    22º01′05″N.

Wednesday, July 21, 2010

Preparing for Summer Learning Loss

We've heard a lot of talk in the news lately about summer learning loss in K-12 students. First Lady Michelle Obama recently added the importance of summer reading to her campaign to get children leading more active, healthy lifestyles; numerous articles in educational journals have explored the achievement gaps that are directly attributable to the summer break. But what, as educators, can we do to address this inevitable loss of knowledge when our students come back into the classroom? And, do we address it differently with undergraduate students than we do with K-12?

There is plenty of literature to support parents in preventing summer learning loss in their own children, but little in the way of how to handle the loss as an educator. That's why we would love to hear how you start off the school year.
  • Do you spend time reviewing material from the previous year?
  • Do you ask students to take assessments so that you know what they've retained?
  • Do you assign summer coursework so that their minds stay fresh?
Share your ideas with us here -- help other educators begin to prepare for September with some new techniques and approaches to get students back up to speed in record time.

Tuesday, July 13, 2010

You Have Until August 2nd!

Yes, that's correct. If you would like to have some input into the standards that will be used to assess science knowledge across the US, you have until August 2nd to review and comment on the National Research Council's draft of the Conceptual Framework for New Science Standards.

The standards are geared toward K-12, but we know that what happens at the lower levels significantly effects what happens later on. If you are involved with teaching or learning science in any way, give some thought to the core knowledge that students should have upon either entering the workforce, or beginning an undergraduate science degree. Those of us on the front-lines are the ones who know best what is lacking in our current approach to teaching science.

A survey will be posted on the National Academies website July 14th for those who would like to offer their feedback.

Thursday, July 8, 2010

Breakthrough in HIV/AIDS Prevention

In the US each year, an estimated 56,300 people are newly infected with HIV and, according to the CDC, approximately 21% of HIV-positive individuals don't even know they carry the virus. It is a disease that continues to spread, despite widespread education efforts, and to many people without the resources for medical care sounds the death knell. But now there's more hope.

Who would have thought that just 30 years after the first known cases of HIV and AIDS were recorded in the United States we'd have a potential cure? In tomorrow's edition of Science, NIH-sponsored scientists explain how they have identified two antibodies, known as VRCO1 and VRCO2, that are able to prevent most known HIV strains from infecting human cells. This could lead not only to the development of an HIV vaccine, but to vaccines for other diseases as well.

As described in the research, the scientists devised a new molecular device that isolates antibodies produced in the blood of HIV-positive individuals. The device itself is a protein that is designed to bind with a vulnerable spot on the virus, thus blocking its ability to infect other cells. According to the researchers, the site where the protein binds happens to be one that is relatively unchanging, which explains why it is able to neutralize a wide variety of HIV forms.

Not only does this discovery mean that we could see an end to HIV/AIDS in the no-too-distant future, but the research methods employed could lead scientists to trying similar things with other diseases. Tomorrow's release of the research could mark the start of an entirely new approach to vaccine-creation, and have significant effects on the world's health moving forward.

Tuesday, July 6, 2010

Novel Research Methods May Help Protect Species

Creativity plays a highly important role in scientific research. Often, the more complex the question, the more creative the approach. This is especially true for those studying elusive or endangered species, as researchers must design projects that will bring them close to their often hard to find subject.

In a study just released in the journal Nature, researchers working in Columbia, South America, created a novel method for identifying the population of cotton-top tamarin, an animal popular in the exotic pet trade. As the paper explains, two teams of four researchers walked parallel in strip transects through the historic distribution area of the cotton-top tamarin. That in itself isn't particularly unique. What was unique, though, was that the third member in each party carried a Bose Acoustic Wave Music System II that played the long calls of adult cotton-top tamarins living captive at Disney's Animal Kingdom. (The fourth person in each group walked behind and documented the number, demographics and location of the animals responding.)

Read the full research article here.

The project demonstrates how important it is to know your research subject when designing methods. The approach relies heavily on the understanding that tamarins are social creatures and will come toward the call of new individuals, rather than run away. Despite documented research confirming this behavior, the research team tried their technique first on known populations of tamarin living in their long-term study site. Through this trial they confirmed that the animals would not only respond vocally to the playback, but would come close enough that they could be seen and documented.

The results of this project showed that the population of cotton-top tamarins in the Columbian forests have declined significantly since the 1960s -- from the tens of thousands to the thousands. As a result, they have been reclassified as "Critically Endangered" and placed on the "World's 25 Most Endangered Primates" list.  With the help of the team's research, Columbian officials are making the conservation of forest a priority in protecting this species -- though deforestation and urban development continue to be a massive threat.

Image copyright Hogle Zoo, 2010.