Science

You are currently browsing the archive for the Science category.

In our recent interview with Bill Nye, he reminded us that the hardest thing for everyone to understand about the environment is that every single thing you do affects everybody in the whole world.”

Inspired by his words, I decided to replace some lightbulbs in my house with CFLs (compact flourescent lightbulbs). While I have been slowly replacing lightbulbs with CFLs as they burn out, I finally replaced a good number before they were burned out. It also helps that many companies are offering CFLs in different sizes and more attactive casings (i.e. flood lamps, decorative bulbs, etc). Thus, more than 90% of the lightbulbs in my house are now energy efficient.

Many stores will make this conversion easy for you with multi-packs and rebates as well. Energy Star even has a “choose a light” guide for you to help you decide which CFL suits your needs best. Nye suggests finding CFLs of the color you like, but with all things, the higher quality ones are usually more expensive.

Hear Bill Nye’s Opinions on CFLs
at www.nsta.org/laboutloud

So you go to the store and you buy one [compact fluorescent light bulb]. Ok, but if you replace every lamp in your house, or every lamp in the main rooms… Replace every one of those lamps, and you will see your power bill go down… Now there are some whining, unbelievable-freakin’ whiners out there who tell you that we can’t change to compact fluorescents because of the mercury – “there’s no way to get rid of the mercury that’s in those lights and it’s gonna kill everybody.” So let’s keep in mind that it was the year 1951 when American industry went to buying more fluorescent lamps than incandescent lamps. That is to say, if you work at any sort of factory anywhere, they have fluorescent lights – ‘cuz it’s so much cheaper. And so those lights are required by law to be recycled and the mercury recovered. And there are services that recover the lights and recover the mercury. So we just gotta do the same thing for domestic consumers – for people that buy ‘em for their houses. For cryin’ out loud – this is not, if I may, rocket surgery. This is actually a little more complicated that: trying to motivate everyone to do the right thing with regard to their old lamps. And of course it can be done; it’s a metal. Who doesn’t want to recover a metal? It’s valuable, it’s shiny, you can see it – of course you can do it. Download the Podcast

CFL Links:

Tags: , , , , ,


Saturday, February 9th @ 7:00 PM
Lawrence University; Appleton, WI
Science Hall, Room 102

Please join us for this special Darwin Day event on Saturday, February 9th at Lawrence University. This event is designed to celebrate Darwin’s birthday and contributions to science. All students, educators and scientists are welcome. Food and door prizes will be provided.

Event Schedule
7:00 PM Keynote Presentations & Discussions (below)
8:30 PM Movie: Flock of Dodos
10:00 PM Social at the Viking Room on campus

Genetics and Speciation
Beth De Stasio, Raymond J. Herzog Professor of Science
& Associate Professor of Biology, Lawrence University
Using one or two recent examples, we will explore the connection between genetic change, phenotypic change, and speciation. Advances in our ability to dissect the genetic component of complex traits such as an organism’s morphology and color have allowed scientists to understand the changes that have led to reproductive isolation and subsequent speciation within particular populations. We will discuss the importance of reproductive isolation to speciation and mechanisms by which organisms can be isolated even when living in the same environment. Two examples will be explored.

Evo-devo and its contributions to Darwin’s legacy
Brigid O’Donnell, Postdoctoral Fellow of Biology, Lawrence University
Evolutionary developmental biology (or “evo-devo”) is a relatively new field of biological inquiry that elegantly illustrates both common ancestry and descent with modification in organic beings as envisioned by Charles Darwin. Evo-devo has provided us with a powerful perspective to explore the proximate mechanisms underlying the genesis of form as well as the evolutionary “tinkering” of developmental pathways across multiple scales of biological organization (from genes to entire structures!). I will highlight two specific case studies that have supplied exciting insights into the origin and evolution of the phenotype: the origin of body plans and the developmental basis of eyespot patterns in butterfly wings.

Coevolution of hosts and their parasites
Judith Humphries, Assistant Professor of Biology, Lawrence University
The coevolution of parasites and their hosts is often described as an “Arms Race”, where for example, the parasite evolves to increase the probability of infecting its host but in response, the host coevolves to better defend itself against the parasite. This is consistent with the “Red Queen Hypothesis” where both host and parasite must continually evolve in order to maintain fitness relative to each other. The relationship between parasitic brood birds such as cuckoos, and their hosts is often used to exemplify this hypothesis.

Please respond to president07@wsst.org if you plan to attend
Sponsored by Lawrence University and
The Wisconsin Society of Science Teachers

Tags: , , ,

Inspired by Dale Basler’s stop-motion video project in physics, I recently had my freshman biophys students make videos that examine the factors affecting the rate of a chemical reaction.

We used a lab from an Addison-Wesley Chemistry lab manual entitled “Factors Affecting Reaction Rates”. This lab was ideal, as the instructions are already neatly divided into 4 parts, whereby each part examines what can affect the rate of a chemical reaction (temperature, concentration, surface area and use of catalyst). Students were divided into 8 groups of 3 (2 groups for each concept).

These were the guidelines for the videos:

  • 1-2 minutes in length
  • Describe setup & document experiment
  • Discuss results (with graph or data table)
  • Show balanced reaction
  • Discuss concept

This was a 5-day project (2 days in lab, 1 for taping, and 2 for editing in the computer lab). I gave the students just the basics in order to use Windows MovieMaker, and helped them on-the-fly with questions.

Besides the final project, perhaps the best part of the project was viewing them all in class. Not only were we able to discuss the concept in each video, but students also critiqued each video in content and in quality. This evolved into a really productive discussion on how important it is to be able to communicate science effectively.

This turned out to be a great project that the students really enjoyed. The only negative comment I heard was “the reactions were kinda boring” (all kids want fire and flames). Now that I know the students can handle this type of work, my mind is spinning on what movies they can make in the future using other science tools – graphical analysis, digital microscopy and RasMol (molecular visualization software) come to mind immediately.

Here is an example video:

 

 

Tags: , , ,

Today is the Friday of Homecoming week, and you can feel the energy pulsing through the students and staff in the building. During the week we have plenty of spirit building activities, such as dress-up days, music in the halls, voting for homecoming court, penny wars between the student classes, and a float-building party with bonfire and games on Thursday night.

As we get closer to the pep assembly and game on Friday, the students’ minds drift farther away from the classroom. This can be an obvious frustration for any educator who doesn’t want to waste class time. I see many teachers showing movies for entertainment, giving large tests, or simply shutting down and letting their classes talk the entire hour about their weekend plans.

 

One way that I engage my chemistry students right up until the pep assembly is with a margarine lab. Essentially, the students select a margarine sample, heat it up until is separates into oil and water, freeze the oil, and extract the water. By getting the mass at each step, they are able to easily calculate the percent of water in margarine.

I am watching my students do the lab right now. They are active, engaged, enjoying the oh-so-buttery-good smell in the lab, and even doing a little math. In fact, it’s the same math that we will see in the future when calculating % composition. It’s perfect activity to keep my students active and even trick them into learning.

On a day like this, what are your tricks to keep students motivated to learn?

Tags: , , ,

Here’s a few neat sites that have some free science videos:

Tags:

In December (2005), the journal Nature conducted a scientific study of the accuracy of scientific entries in Wikipedia (on online, free & editable encyclopedia) vs. Encyclopedia Brittanica. You can view the original results here.

Yesterday, Encyclopedia Brittanica struck back, with this lengthy press release. Ultimately, they requested Nature to retract their article. A summary of the release (albeit jaded) was compiled by arstechnica. A more balanced review can be found at The San Jose Mercury News. It should be noted that it took three months for Encyclopedia Brittanica to respond, and this document was internally written without external review.

As expected, Nature wrote back defending its original study, mainly citing how they obtained each article and that the reviewers were blind as to the source (EB vs. Wiki). This statement elegantly sums it up: “We realised that in some cases our reviewers’ criticisms would be open to debate, and in some cases might be wrong. But this applied as much to criticisms of Wikipedia as of Encyclopaedia Britannica.” At the end of the letter, Nature firmly defends its original study by stating: “We do not intend to retract our article.”

This argument is a grand example of what we are teaching about the internet, and what the future of the internet can be. For instance, it highlights the concerns about an open and editable internet versus one where users pay for their content. There are pros and cons to each approach, and we can easily highlight them in the classroom.

Tags:

Tonight, I accidentally stumbled upon a show on The History Channel entitled “How William Shatner Changed the World”. As a Star Trek fan (but not a full-fledged Trekkie), my interest was immediately grabbed. Based on his book “I’m Working on That”, Shatner hosts and narrates a show that postulates how Star Trek has influenced the technological society that we live in today.

In one comical moment, Shatner describes how the show’s creators developed their vision for the future: they made it up! Insights into the show also revealed that the infamous transporters were developed because the shuttle craft weren’t ready in the first few episodes. And tricorders were actually recycled salt shakers!

Besides these bits of trivia, the show emphasized that the vision of Star Trek invigorated the technological age that we live in, complete with personal computers, cell phones and non-invasive medical techniques. This show immediately reminded me how imagination can directly lead to innovation, and how we as educators can inspire our students to bridge this gap.

Catch the show again on The History Channel:

Shatner Internet Fun:

Tags: , ,

Newer entries »