Wednesday, March 31, 2004

An update: grading and remodeling

So far I've had a good, if busy, spring break. I spent all weekend reviewing three draft chapters for a textbook. Each chapter took about 8-10 hours, and I ended up writing about 10 pages per chapter. I enjoy doing the reviewing: it's nice to be able to provide feedback, and it forces me to read up on new things. I've also worked around the house, gotten some lectures written, graded my students' exams, and posted a few handouts. One of my students' possible assignments for the semester is to observe animals in a natural area, so I posted that assignment up early in the hopes that some students would do it over break. One student has already IMed me saying he's planning on taking a trip to some tide pools.

In other news, our long-stalled remodel is finally getting started again. If you're wondering why you haven't heard about a remodel, it's because the project stalled before I started blogging. Back in September of last year, the contractor we'd hired to do the bathroom remodel for our newly purchased house just stopped showing up right in the middle of the job. I'll have to tell that story another day.

We've spent much of the past few months planning exactly how we want to complete the job, and this week we've had three window installation companies come by to give us quotes. We prepared a three page quote request detailing what we wanted done to the three windows, including some simulated before-and-after pictures we made with Photoshop (yes, we're geeks). Apparently we went way overboard, as all three estimators have been amazed at the level of detail, and said that we did their job for them. Chalk it up to overcompensation for a lack of planning with our first contractor.

Unfortunately, things are not looking up so far. We've priced the windows separately through an independent supplier, and for the first (and only) quote we've gotten back they've priced the windows 73% above what we can get them for, and are charging nearly $3,000 for labor. Granted it's not the simplest job in the world as we're enlarging the windows and there's siding on the house to deal with, but for three windows that seems a bit high. And, to top it off, the estimator who stopped by today refused to give us a quote because he never enlarges windows (though he referred us to another company that does).

I'm off to Philadelphia later today, and will be there until Monday. I probably won't be able to post while away, but will return to my regularly scheduled posting on Monday night / Tuesday. Have a great week all!

Friday, March 26, 2004

Spring Break

Today is the first day of my spring break, which lasts through next week. Unfortunately, I'm incredibly behind on work and thus will be taking a short break from regular posting. I have three sets of papers (each consisting of ~80 2-3 page papers), one set of exams (160 of ‘em), and two week's worth of lab assignments to grade, three book chapters to review for a publisher (that were due last week), a bunch of handouts and lectures to prepare, and much housework that has been put off. I need to do all this before Wednesday, when I fly off to Philadelphia with my SO for a short vacation. Looks like it'll be another busy spring break.

Of course I don't feel too alone, since my students' plans for break generally consisted of two of the following three activities: sleep, work, and study (mostly for chemistry). Vacation was not a word in their vocabulary, sadly.

I apologize for the posting break; talk to you again soon!

Thursday, March 25, 2004

Strange things scientists carry with them

In response to my post about the biologist carrying a seal head onto a plane, Qov (who writes bo logh, a blog in Klingon) suggested starting a topic on strange things scientists carry with them. I think it's a great idea, so here goes.

I'll start with the items Qov included in her comments:
"A researcher came to visit my supervisor and was stopped at the airport X-ray machine for having what appeared to be a severed human foot in her hand luggage.

She did have the bones of a human foot in her luggage, encased in a plastic that had similar x-ray characteristics as human flesh. She was working on technology to improve x-ray plates, and the foot was her test pattern.

I know another chemist who got in trouble for carrying a cobolt sample on public transport."
I've carried my fair share of strange items around with me; here's a few that I can think of off the top of my head:
  • Fishing poles in the desert: As an undergraduate I worked on lizards, specifically Sceloporus occidentalis, the western fence lizard. We caught these lizards in the wild, and the easiest way to do this was to tie a small noose onto the end of a fishing pole, and then slowly wander around the desert (or other natural area) with said pole looking for lizards. Once a lizard was spotted we attempted to slowly lower the noose over its head to capture it, using the fishing pole to allow us to stand as far back as we could. I'm certain we looked ridiculous wandering around on swelteringly hot days with fishing poles and no lakes or streams in sight.

  • Pieces of dead cacti: While working in a lab studying desert Drosophila species, my labmates and I drove around the desert looking for dead and rotting cacti. Once found, we collected pieces of the cacti (with appropriate permits) and brought them back to the lab to use in food for the flies. I even carried bags full of this rotten cactus across the border to our field site in Mexico.

  • Fly rearing equipment: When going on the above-mentioned trip to Mexico for some desert Drosophila field work we brought our fly rearing equipment with us, including hundreds of small vials partially filled with a tan-colored agar-based fly food. The Mexican border agent discovered these vials and gave us a hard time over them; he seemed relatively certain that they were used for manufacturing drugs, and wouldn't accept our explanation that we were rearing flies in them for scientific purposes (sometimes the truth just isn't a good cover story). He held us up for quite a while and made many allusions to wanting bribe money, but we were eventually allowed to go on our way freely. My advisor reported eating the fly food in the past to prove that it wasn't illicit, though she didn't have to do that this time.

  • Datura (Jimsonweed, Angel's Trumpet, etc.): The caterpillars I worked on as a graduate student grew native in the area on Datura wrightii, and thus on many occasions I harvested Datura either from the wild or a batch we had planted at a local field station. While returning from a conference in California one time I made a point of stopping along the highway at every plant I saw to check for caterpillars and collect leaves. What's wrong with native plants, you ask? Well, Datura happens to be an extremely toxic member of Solanaceae (a family of plants containing tobacco, tomato, eggplant, potatoes, and many more) that some people have used as a hallucinogen (see this DOJ report). Thus, you can imagine my concern that a police officer might come along and suspect I was collecting the leaves for my own use rather than as caterpillar food. Note: if anyone doubts the toxicity of Datura, one of my undergraduate assistants, while trimming some leaves, got a tiny drop of sap in one of her eyes. Both of her eyes remained dilated for three days.

So, my dear scientific readers, what odd things have you carried around for scientific purposes?

[Updated to correct the gender of Qov, with many thousands of apologies going to her. I should have known better.]

Wednesday, March 24, 2004

Baby lions and caterpillar growth

All The Stuff I Couldn't Fit in My AIM Profile is a blog I just found, thanks to her link to one of my posts (always a sign of good taste, if I say so myself). She's got some neat pictures of a baby lion - the first one was taken on November 15th, and the second one taken on January 6th. The difference in size is astounding, though the entomologist in me reminds me that the caterpillar Manduca sexta grows much more quickly on a mass-specific basis (approximately a 10,000-fold increase in mass in just about 3 weeks). If an eight pound human newborn grew as quickly as M. sexta, in 3 weeks it'd weigh 40 tons.

Tuesday, March 23, 2004

Invisible Adjunct is signing off

Read about it here. Invisible Adjunct was one of the first academic blogs I read, and her take on adjunct (and other) issues was always refreshing. It's sad to see her go; I wish her luck.

[update 3/24/04, 4pm P.S.T.: There are now more than 127 comments and 21 trackbacks on Invisible Adjunct's final post, and it's only been about 24 hours since the post was made. Wow.]


  • Droplet: Amateur Microscopy of the Protozoa has some beautiful pictures of protozoans, along with taxonomic and general descriptions of each pictured organism. There are currently 184 pictures and 59 genera represented. If anything, I'd suggest that Mr. Rotkiewicz drop the "amateur" from the page's title. (via Pharyngula)

  • Michael at The Magic Angle, a new science blog, also replied to Pharygula's acupuncture post (my reply is here). He makes, among other things, the very important point that "there are always the anecodotal tales of some treatment working - but in any adequately sized population you'll find some people who make progress regardless of treatment." As a side note, maybe Semantic Compositions can tell me why I first typed Michael's blog name as "The Magic Apple"?

  • The Lord of the Rings Action Figure Storybook has recreated the Lord of the Rings movies using action figures. They've completed both the Fellowship of the Ring and The Two Towers; they make good light reading.

  • As a final note, thanks to both Semantic Compositions and Pharyngula for expanding on my misconceptions post - I appreciate the links! I believe they're the prime cause of my daily hits suddenly tripling.

HIV research

Rivka at Respectful of Otters discusses some recent HIV research showing that people who exhibit immunity to certain strains of HIV (e.g. their HIV-infected partner's strain) don't necessarily have immunity to all strains of HIV. I'd only recently learned that some people show limited immunity to the virus; this makes things even more complicated.

Monday, March 22, 2004

Alternative Medicine

Pharyngula recently posted about a poorly designed study that attempted to show acupuncture had medical benefits for headache sufferers. I'll leave him and his links to tear the study apart, but suffice to say that the study was lacking a critical control group, and thus is of very little use.

I've often thought that literature on alternative medicine makes for great reading, just because there's so much quackery in it. Let me be clear: I'm not thoughtlessly against alternative medicine. Rather, I'm against anything that claims to be medical treatment without solid evidence showing it is safe and beneficial for the conditions it claims to treat.

It's interesting to look at chiropractics from this perspective, especially since a lot of people visit chiropracters regularly (8.75% of the 65,000 respondents in a Consumer Reports poll reported in May 2000). I had a chiropractor as a student, and he ardently believed in what he did (he also had an amazing understanding of human anatomy). Take a tour around the web with Google looking for "chiropractic effectiveness" and you'll find lots of lists of poorly designed studies attempting to support chiropractics.

There appears to be very little solid evidence that chiropractics does much of anything; the single area where it seems to have any scientifically verifiable effect is the relief of lower back pain (e.g. this link). Even for lower back pain, some relatively new meta-studies (here and here) have concluded that chiropractics is not superior to conventional treatments for lower back pain (the Chiropractic News Digest has a nice summary of these two studies and the chiropractic industry's response).
"For patients with acute low back pain, spinal manipulative therapy was superior only to sham therapy (10-mm difference [95% CI, 2 to 17 mm] on a 100-mm visual analogue scale) or therapies judged to be ineffective or even harmful. Spinal manipulative therapy had no statistically or clinically significant advantage over general practitioner care, analgesics, physical therapy, exercises, or back school. Results for patients with chronic low back pain were similar. " (link)
"A meta-regression analysis of the results of 26 RCTs evaluating spinal manipulation for acute and chronic back pain reported that spinal manipulation was superior to sham therapies and therapies judged to have no evidence of a benefit but was not superior to effective conventional treatments." (link)
The second paper quoted above also concluded that massage therapy was effective, while there weren't enough good studies of acupuncture to come to a conclusion. It seems that based on these papers chiropractics is similarly effective to conventional treatments for lower back pain. However, questions of safety still need to be addressed. For instance, see this report that says,
"The most valid studies suggest that about half of all patients will experience adverse events after chiropractic SM [spinal manipulation]. These events are usually mild and transient. No reliable data exist about the incidence of serious adverse events."

Sunday, March 21, 2004


A friend invited my SO and me to join him for some kayaking yesterday. We paddled around a local harbor for about three hours, and had a very relaxing and enjoyable time out on the water (especially after we figured out how to go straight). Unfortunately, my SO and I are novice kayakers, and our muscles are reminding us of that today. So I did a bit of looking and found a few neat tidbits on what causes muscle soreness.

Berne and Levy's "Physiology" (4th ed.) had the following to say:
"Activities (such as hiking or particularly downhill running) in which contracting muscles are stretched and lengthened vigorously are followed by more pain and stiffness than are comparable efforts such as cycling. The resultant dull, aching pain develops slowly and reaches its peak within 24 to 48 hours. The pain is associated with a reduced range of motion, stiffness, and weakness of the affected muscles. The prime factors that cause the pain are swelling and inflammation that result from injury to muscle cells, most commonly near the myotendinous junction."
The type of muscle contractions they're discussing are called eccentric contractions, wherein muscles are contracting and lengthening at the same time, and this type is most likely to cause muscle soreness. This contrasts with concentric contractions, in which the muscle shortens while contracting, and isometric contractions, in which the muscle stays the same length while contracting.

While regular training can help reduce muscle soreness, just a single bout of eccentric exercise will reduce the muscle soreness experienced after a later eccentric exercise bout, even if the events are separated by many weeks (up to 24 weeks in some reports). Possible mechanisms for this acclimation are discussed in these two articles (2nd link is a PDF), though I'm sure there are many more papers on the topic.

One abstract also included the interesting observation that "although training is considered to prevent muscle soreness, even trained individuals will become sore following a novel or unaccustomed exercise bout." Somehow the knowledge that even trained athletes get sore is very comforting right now.

Saturday, March 20, 2004

Happiness is Calvin and Hobbes

I just discovered that a few sites (wxinfo and uComics) syndicate reruns of Calvin and Hobbes (wxinfo's page & XML feed; uComic's page). Through the XML feed I can now relive my fond memories of reading Calvin and Hobbes over breakfast many years ago. I wish there were more artists like Watterson around ...

If you're dying for more Calvin and Hobbes information, check out the Calvin and Hobbes Resurrection.

911 or 912 days?

There has been a decent amount of discussion on some blogs regarding the observation that the Madrid bombings occurred 912 days after the 9/11/01 attacks in the US (leaving 911 days between the two events). For anyone interested, the Snopes folks have a nice article clarifying the date calculations.

Science Night

Last night my campus had its annual science night open house; 3,000 local elementary school kids and their parents were invited to attend for free. Most of our science faculty donated their time and opened up their labs, including our chemists, marine biologists, anatomists, geologists, microbiologist, astronomer, and physicists. There were a few paths set up to guide people around the campus, and while many of the labs were filled with static displays of specimens or other interesting materials, some had demonstrations going continuously through the night. I didn't get a chance to wander around, but my SO did and reported that the industrial tech people had participants building paper airplanes to fly off their balcony, the marine science people had a "touch the wildlife" tank full of intertidal critters, and the chemists had a ton of demos including a non-Newtonian fluid, burning metals, odoriferous chemicals, and a bottle containing iodine crystals and gas that was labeled "Iodine: how sublime" (ugh).

My displays consisted primarily of various skulls, skeletons, and preserved birds, though I threw in some invertebrates for the fun of it. To draw people into the room I positioned our horse and saber-toothed tiger skulls so they looked out the door, with horse limbs not far behind. While this tactic worked on many, some kids looked in and then promptly ran away. I had some student helpers, and at least a few hundred people worked their way through the lab during the evening.

The most enjoyable aspect was how excited the kids and parents were at seeing the various items; almost everything I had out was real (not casts or models), and that impressed most of the visitors. There were countless "wow"s and "cool"s to be heard the entire evening, and many parents thanked me (and our other faculty) for having the campus open. The funniest event of the night was a woman who picked up a dried centipede and then said to her kids, "Look, this is what bit Daddy in Hawaii!"

Here are a few pictures from the evening:

Last night was what teaching is all about – sharing some of what I know with the people around me, and it was invigorating to see such joy at the things I use every semester.

Only a biologist

Here's some good reading for your morning coffee: a biologist was stopped after trying to carry a seal head onto a plane. The sad thing is, I can sympathize with him ...

Friday, March 19, 2004


Carl Zimmer at The Loom has a post discussing the recent Science paper by Thomas et al. that shows a significant decline in bird, butterfly, and plant biodiversity in England over the past half century.

What really grabbed my attention, however, was Zimmer's introduction to the piece:
"When I ask scientists what's the biggest misunderstanding people have about their work, they often talk about how they know what they know. People tend to think that a scientist's job is to gather every single datum about something in nature--a mountain, a species of jellyfish, a neutron star--and then, simply by looking at all that information, see the absolute truth about it in an instant."
This is definitely a common misconception. For biologists, another related misconception is we're typically expected to know both a) every last biological detail about our chosen organism of study, and b) basic information about every organism on the planet. I get the impression that memorizing all these facts is what most people think biological education is supposed to consist of.

For instance, I worked in an insect lab during graduate school (investigating caterpillar digestive physiology) and we'd commonly get people calling or coming into the lab asking for information on some random insect they found in their yard, a park, or wherever. When we couldn't even tell them what type of insect it was, let alone the details of its life cycle ("Um, we think it's some kind of beetle larva, but we're really not too sure ..."), the disappointment was evident. Now that I'm teaching zoology it's even worse: any animal is fair game. While I enjoy the questions, I do at times wish people would realize that I'm not a walking reference book of taxonomic information.

Thursday, March 18, 2004

Ernst Haeckel images

Double cone image by Ernst Haeckel / Scott DravesA number of Ernst Haeckel's images have been released by Scott Draves as PNG files. Mr. Draves is releasing the images under a creative commons license; here are the details: "The alpha (transparency) channels in these PNG files are released under the attribution share-alike Creative Commons license. The original bits are from Ernst Haeckel."

I've reposted one of the images here. There are a ton more, and they're beautiful.

As a side note, kudos to Mr. Draves for having a mouse prominently pictured on his homepage. Three cheers for rodent fans!

(via BoingBoing)

In-class response system update: the positives

I've previously discussed the negative aspects of the in-class response system I'm using this semester. While many of the negative aspects are technical problems (installation, using the software, transmitter reliability, etc.), the positive aspects are primarily pedagogical. In this post I'll summarize how I've used the system to date, and then discuss the benefits of the system.

How I've used the system:

I'm using the system primarily as a participation encouragement tool, and have tried to make it as low-stress as possible for the students. I typically ask two to four questions in each lecture using the system, and the students have around two minutes to answer each one. To prevent the system from feeling like a pop quiz, I give students one point per question they answer, regardless of whether their answer is correct. This leaves me free to ask difficult questions designed to motivate discussion without causing the students undue worry, and it also removes much of the possible motivation for cheating or collusion.

Currently I use two workarounds to help ease the pain of technical problems, both of which I derived from Randy Phillis. First, students can turn in a handwritten list of their answers in lieu of using their transmitters for four days a semester (there are ~28 lecture days in the semester). Second, to account for the possibility that some answers aren't received by the system, anyone who answers 90% of all possible questions will get 100% of the possible participation points.

I've asked a mix of question types, including questions on content that hasn't yet been introduced, basic recall questions on a topic we've just covered, and extrapolation questions designed to encourage discussion. The discussion questions have been the most interesting, and they're the ones I try to use most often. Straight recall questions have been OK, but it's hard not to say, "The answer is B, here's why, let's move on," which gets pretty dry after only a few times, and likely hinders participation on the discussion questions (e.g. "He'll just tell us the answer anyway, so why should I bother raising my hand?"). However, even the recall questions can provide useful data on student comprehension.

Questions on content that hasn't been introduced yet are probably the students' least favorite of the three (based on my limited student survey data), and I'll grant that they can be awkward if the topic is completely unfamiliar. However, when they're asked properly, pre-content questions can lead smoothly into a discussion on the upcoming topic and get the students engaged right from the start.

A unique aspect of using this system is that I have no time to prepare my response to the student data: I see it at the same time the students do. While this makes things a bit more stressful, it's fun because it's made my lectures more spontaneous.

Benefits of in-class response systems:

Probably the largest benefit is that the in-class response system provides an easy mechanism for formative assessment during class-periods. By answering a question after a challenging topic, each student is motivated to evaluate their ability to understand that topic, and by seeing the entire class's responses I get an accurate gauge of the class's comprehension.

When instructors ask an open question to a lecture, fewer than ~20% of the class will typically respond (with the percentage dropping as classes get larger; I had a citation for this but can't find it anymore). We've all been in lectures where the three "smart students" answer all the professor's questions, allowing everyone else to relax and not even ponder the question at hand. I've tried to get around this in the past by using a program to call on students randomly, but even then only one or a few students got a chance to speak up. When only a few students answer a question, the instructor necessarily gets a skewed idea of the class's knowledge on any given topic; this system remedies that by allowing every student to answer every question.

When using the in-class response system, the students can't just mentally waffle between answers; they must commit to a single choice. Thus the students have bought into one of the answers, and are more invested in the ensuing discussion about the topic. Conveniently, I also get quantitative data regarding what misconceptions students have, and thus can better guide the class discussion. If I really wanted to be mean I could go into the logs and figure out who picked any given answer and then call on them to explain it, but I wouldn't be that mean.

The answers students submit are also pseudo-anonymous, which makes the students more comfortable. While the students know that I, as the instructor, can go through and see how they've answered any given question, they never have to share their answer with their peers. This allows even the shyest student to answer a question in a large lecture, removes the fear of public humiliation for answering incorrectly, and allows students with non-conformist views to express them more openly. Anonymizing answers is also easy: students can trade transmitters for a specific question, or software settings may allow anonymity.

The system is also a good classroom management tool. The screen displays both the question text and the remaining time to answer the question, and once the timer reaches zero the program automatically graphs the student responses. Students are interested in their peers' responses, and thus as the timer approaches zero virtually all discussion stops, and then there's almost dead quiet as everyone mentally analyzes the graph at the same time. It's pretty amazing not to have to do anything special for 180 chattering students to become quiet and attentive after asking an open question.

The students also seem to love the system. There was a lot of excitement when I first mentioned the transmitters in class, and while the buzz has died down since then, the students are still enjoying the system. I've had multiple students provide unprompted compliments of the system, and I've also done a brief in-class survey asking students how much they like it. Here are the results of the survey:

How much do you like having the PRS transmitters in this class?
Extremely like them 39%
Somewhat like them 43%
Neutral 8%
Somewhat dislike them 5%
Extremely dislike them 4%

If you had a choice, would you prefer this class use or not use the PRS system?
Greatly prefer with 48%
Somewhat prefer with 33%
Neutral 11%
Somewhat prefer without 5%
Greatly prefer without 3%

Would you like other instructors to use the PRS system?
Definitely want 46%
Somewhat want 29%
Neutral 19%
Somewhat don't want 1%
Definitely don't want 6%

Data based on in-class evaluations after about 3 weeks of using the in-class response system; n ranged from 90 to 102 for the three questions. The survey was conducted via the in-class response system, and this may have biased the results somewhat. Students traded transmitters with their neighbors for anonymity.

While the evaluations aren't unanimously positive, I'm quite encouraged by them. One thing that strikes me is that the students had to pay anywhere from $15 to $45 each for their transmitters, and even with that monetary expenditure more than 80% of them would prefer the class have the transmitters, and fewer than 10% didn't want them.

As a final note, the in-class response system is also very flexible, and can be used for any number of purposes. I'm using it to encourage individual participation, but I know of other instructors who use it to promote group work (e.g., give one transmitter to each group of students) or to collect data for later analysis by the class (e.g., in a statistics class).

I'll try to post further updates after I've gotten more experience using the system.

Wednesday, March 17, 2004

Poll providers

I posted up my very first poll last night, and awoke this morning excited to see the voting results. Instead of finding results, however, I found an IM from Semantic Compositions informing me that my poll wasn't working.

I initially decided on CreateaPoll as my poll provider, but it seems like their code didn't agree with Blogger. So, this morning I switched the poll to a new provider, PollHost. I apologize for any confusion or frustration that occurred with the initial poll; it should be fixed now.

I thought I'd list the various providers I've found so far (note: this list is probably far from complete):
  • PollHost: Free, no paid version, ad-supported via ads on the results page, results on a separate html page, and they claim to prevent multiple voting. Their examples make it look like you can't view the results without voting, but there is an option to add a "view" button when making a poll. This is my current provider, and they seem to work with Blogger after a bit of fiddling.
  • Sparklit's webpoll: Free, option for a paid version, results appear on a separate page that may contain ads, and they have the ability to leave comments on the results page.
  • FreePolls: Has both free and pay service, results appear on a separate html page, and it's ad supported when free (with a notice that popup ads may be served directly from the poll).
  • CreateaPoll: Free, no paid version, results appear in popup window. This was my first provider, and they didn't seem to work with Blogger (though I may have missed something).

Tuesday, March 16, 2004

Irrational fears

My SO and I are both practicing biologists (gee, put that way it sounds like a religion, doesn't it?). Considering that we work around animals and other biological materials on a daily basis, we should be free of biologically related phobias. But we aren't; hence this poll.

Which of the following fears/dislikes is most pathetic for a biologist?
Looking at dissected humans
Cleaning up moldy food
Reaching into the body cavity of a store-bought frozen chicken
Free polls from

[update March 17, 2004: votes weren't being registered wtih my first poll provider (CreateaPoll), so the poll is now being run with a new provider (PollHost)]

[update April 16, 2004: I've made a post with the poll results, and updated the page to remove the ability to vote in the poll]

The Political Compass

I just finished taking the Political Compass's two-dimensional test of political ideology (note: the test is linked from their homepage; they want people to read the homepage notice first). After answering some questions users are placed on both an economic scale (left/right) and a social justice scale (libertarian/authoritarian). They have the relative positions of various 2004 US Presidential hopefuls and selected world leaders (world leaders are found on the analysis page after you've answered the questions) for comparison.

Monday, March 15, 2004


Preserving biological tissues is difficult. Bacterial decomposition, dessication, and decay begin taking place almost immediately after death. To date, most biological specimens, be they human bodies donated for study or animals collected in the field, have been either preserved in formaldehyde (or similar chemicals), or frozen. Freezing works well from a molecular perspective, but working on the organism is impossible without thawing, and thus decay. Formaldehyde and related compounds prevent tissue decay at room temperature, but they're relatively toxic chemicals, smell bad, and can drastically change the appearance of tissues over time, especially when the tissues are allowed to dry out, as often occurs during teaching dissections.

A relatively new preservation technique is plastination. Plastination involves removing the water and some fats from a specimen's tissues, and then slowly replacing the water and fat with a polymer that hardens at room temperature. The technique was developed by a German doctor, Gunther von Hagens (note: this link contains pictures of dissected human bodies), and is described in more detail here (note: this link contains pictures of dissected human bodies). Plastination is a unique preservation technique: fine details of most tissue types can be preserved, the specimen is dry to the touch, there is no smell, and the preserved specimen can be kept in the air at room temperature without fear of decay or degradation. I have a pre-dissected plastinated frog I show to interested students, and it has stayed in perfect condition sitting on my filing cabinet for the last year and a half.

Probably the neatest aspect of plastination is that organisms can be pre-dissected, plastinated, and then used for educational purposes. Plastinated specimens can be high-quality materials for teaching internal anatomy, potentially removing the requirement for formaldehyde preserved animal dissections in some courses (though clearly some courses' pedagogical goals do require dissections). Since the specimens are durable, a class-set of plastinated specimens could theoretically last years, reducing animal use drastically.

Dr. von Hagens has set up a museum in Germany displaying plastinated humans for public education. While I regret that I've never been to the museum, I've seen pictures from the displays and they're a beautiful combination of art and anatomy. The museum is filled with plastinated human bodies (all donated) that have been dissected and/or positioned in various poses. One of the best dissections I've seen is prominently displayed all over the web site: he's removed the skin from an adult male and has the man holding it in his right hand. On his site he has a few pictures of plastinated humans in the downloads section, as well as in the shop's poster section. I highly recommend looking at the pictures, but be warned that you will be looking at actual human bodies, not plastic models, so if you get queasy at such things I would recommend avoiding Dr. von Hagens site entirely.

Sunday, March 14, 2004

Donor Tag

If you have too much time on your hands, go play the "Donor Tag" game over at the Red Cross's blood donation page. And remember, since the game is made by the Red Cross, it must be educational ... right?

While you're at it, you can sign up to donate blood too (if you're eligible).

Saturday, March 13, 2004

Health insurance shopping

My SO is currently out of work, and has been since moving out to California in January. Since COBRA coverage would have cost in excess of $400 a month, we've been looking for heath insurance on our own.

Shopping for insurance has been frustrating. The array of choices available is rather baffling, and while we understand most of the terminology employed, calculating the expected cost of each plan given certain medical circumstances has been nearly impossible. For instance, we've been trying to calculate the annual cost of each plan including four normal office visits and a monthly prescription medication, and even given this relatively simple scenario it's been extremely difficult to come up with good cost estimates for many insurers. A big problem has been that we haven't found any good data regarding how much office visits cost without insurance (and, being new to the area, we don't have a regular doctor we can call to ask).

There are six different health insurance companies providing HMO service to individuals in California that we've found currently (Blue Cross, Blue Shield, Health Net, Kaiser Permanente, Pacificare, and Universal Care). Each of these companies usually offers at least two HMO plans and some PPO plans; some offer much more. At Pacificare there are three HMO plans and seven PPO plans (counting different deductibles), and at Blue Cross there are two HMO plans and six different PPO plans. Attempting to compare the impact of the various deductible levels and other plan differences has become a daunting task.

While I'm always a fan of more choice in matters, making an informed choice regarding health insurance here seems very difficult. Most of the insurers don't post the full details of their coverage online, or at least make it difficult to discover the details. Even simple things like the insurer's formulary of drugs is difficult to find; I still haven't found Kaiser Permanente's or Blue Shield's formularies.

The California state government's Office of the Patient Advocate has a 2003 HMO report card that rates the quality of various HMOs, but even that is of limited use since most of the insurers rate relatively similarly in many categories. However, the site breaks down insurers by county, so it's good to at least show what companies serve our area.

Thanks for enduring this rant ...


Madrid te quiero
From El Pais, via BoingBoing


BoingBoing posted a link to Everquest Daily Grind, a site that posts the tales of online gaming widow(er)s. The site is filled with heart-wrenching stories. One of the many posts includes this:
"My live-in boyfriend plays EQ whenever he is not at his job or asleep. He has been steadily spending more time in the game for 2 years. He very seldom leaves the house anymore. He sits in the living room with the drapes drawn at his computer from the time he gets off work until he goes to bed. He is even getting married on EQ. April 1st is the big wedding." (link to post)
In high school I played some modem-based MUDs, but it wasn't until college that I got my first taste of an immersive, text-based MUD (yeah, that dates me). My friends and I spent much of the final few weeks of our freshman year in-game, and it certainly didn't help our grades that semester. The game was incredibly addictive. We did have a great time, though ... the highlight has to be when a friend made an announcement to everyone in the game that he would give all his equipment to the first person who could explain molecular orbital theory.

I've since decided to stop playing MUDs (or MMORPGs) since they're so addictive; I just don't want to feel forced to spend that much time in a game.

Friday, March 12, 2004

Shoe polish

Today I polished my shoes. Yes, this is worthy of a blog post. Why? Because this is the first time I've ever polished shoes.

I've typically just bought new work shoes when my old pair wore out, but my current pair of brown shoes turned out to be incredibly comfy and long-lasting. The only problem was they looked terrible (as the picture below shows).

shoe pre polish

So, tonight I broke out some ancient shoe polish and polished them. The picture below is the same shoe after polishing and adding a new $1.50 pair of laces; I can hardly believe the change.

shoe post polish

Why haven't I polished shoes before?

And now we return to our regularly scheduled programming; I promise that this will not turn into a fashion blog (as if there were any doubt).

Thursday, March 11, 2004

Instant messaging benefits

Thursday is finally over! While I came into this week incredibly relaxed (getting 25 hours of sleep in a 48 hour period will do that, especially when combined with an incredibly relaxing location), this week has ended up being just as stressful as any other week.

As a result of this week's stress I didn't have enough time to properly set up my weekly knowledge check, and ended up messing-up a few of the settings (the primary problem was that the release date was wrong). Upon getting back to my office after lab tonight I got a friendly IM from a student who asked why the knowledge check wasn't available. After I fixed the release date, she then kindly pointed out my second error: there were too few questions being selected from the question pool. What a great example of how useful IM can be, and how helpful (and honest) students can be.

Oh, I also had another funny IM exchange today. I had a student IM me around noon asking a question about lab, which he then followed up with "It's 12:15. Shouldn't you be out to lunch?" Since I barely have time to eat lunch at my desk most days I couldn't help but laugh ...

Wednesday, March 10, 2004

In-class response system update: the negatives

As I've discussed before (here, here, and here), I'm using an in-class response system for the first time this semester in my 180-student zoology lecture. The system is designed to encourage participation in a classroom setting. Students answer questions using handheld transmitters, and the answers are automatically tabulated on the computer at the front of the room. See this post for a more thorough explanation of the system.

I've now used the system for four weeks, and overall am quite pleased (Educue's Personal Response System is the brand I'm using). However, there have been a few speed bumps and potholes on the road, and I'll talk about those in this post. In a future post I'll discuss the benefits.

Installation was deceptively easy. We used Velcro to attach the four receivers to the wall, and connected the units to the computer with cables provided by the manufacturer. Unfortunately, the Velcro failed. During my first lecture with the PRS system installed, one of the receivers at the front of the hall fell off the wall, bouncing loudly on a metal stool. All of the four receivers have now fallen off the wall at least once, and to prevent more loud lecture interruptions I've been taking down the receivers after each lecture.

It appears that the Velcro has been strong enough to hold the units onto the wall; the problem is with the glue attaching the Velcro pads to the wall. I've ordered some mounts for the units that screw into the wall ($7 each from Educue), and these should solve the problem.

The second major problem is that students have had difficulty acquiring the transmitters. The transmitters were bundled with all new textbooks for my course, but there were initially no transmitters available separately in the bookstore, as the bookstore staff wanted to force students to buy new books and were worried about returns. They finally agreed to stock the units separately, but ordered only a few units at a time and priced them with a high markup. I still have a few students who are waiting to get their transmitters; primarily these are students who bought them earlier and subsequently lost them, but it's been taking a week or more for students to get the units.

The third problem has been with units breaking. I've had three students report that their unit has broken after only four weeks of use. I suggested that the students go to the bookstore or the manufacturer and see if they could get a replacement, and I believe that they've been able to acquire replacements without a problem (but am not certain). The failure rates seem relatively high, and if the system was being used for quizzes or tests this would have been a significant problem. Additionally, students regularly forget (or misplace) their transmitters; in nearly every lecture I've had at least two or three students who didn't have their transmitters on hand.

Even with functioning units in class it's not clear that every student is able to respond to every question. The transmitters are a bit difficult to aim, and each individual receiver can only receive one signal per 1/10th of a second (or so), meaning that if multiple students simultaneously send a signal to one receiver only the first student's signal will be received. To account for this, the student transmitter ID numbers are displayed on a grid on-screen whenever a response is received. However, since I need to devote the lower half of the screen to the question text, the grid can get pretty small and with a large class it's difficult to see when each student's response comes in. I've had students repeatedly say that they're unsure whether their answers are being received by the system.

The software that Educue ships with the unit is another problem. After a bit of time playing with the program I've been able to use it easily in class, but it's far from intuitive. There are at least seven separate types of files that can be loaded or saved at one time: session files, settings files, question properties files, name files, class files, answer files, and grade book files, to name the ones I can think of quickly. I've had the program stop receiving signals at least twice, and had some annoying errors (and data loss) when the program tried to save files to a directory I didn't have access rights to.

These units are often marketed to be used as quiz and testing tools (touting paperless, automatic grading), and based on the problems that I've seen so far I'd have to say that they would probably not make a good testing tool. The two other in-class response system users I talked with over the weekend at the conference had very similar opinions, so I don't think I'm alone here.

So, what are the systems good for? They're excellent for encouraging participation and conducting formative assessment. Even considering all the negatives, I've enjoyed using them this semester, and plan on continuing to use in-class response systems in the future.

[Update: I've posted a discussion of the benefits of the in-class response system here]

Tuesday, March 09, 2004

Pictures from Sundance

As promised, here are a few pictures from Sundance:

icicles spacer snowy stream spacer mountain through glass

The picture on the left is of some icicles backlit by the morning sun, the center image is of a snow-lined stream that flows through the resort, and the third picture is one of the mountains surrounding Sundance, as seen through a very large window.

Back from Sundance

I got back from my conference in Utah last night, and now have to catch up on all the work that I didn't do over the weekend, so this will be a brief post.

I won't be talking much about the details of the meetings, but it was quite worthwhile and enjoyable. There were five faculty attending, all of whom taught intro bio at the college level, along with a bunch of publishing people. It was great fun to chat with the other faculty about the challenges they faced teaching intro bio; I had some good discussions about how to best use in-class response systems, and will try to post an update on that soon.

The meeting was held at the Sundance Resort, where they'll remind you in all their printed literature that Sundance is the town Robert Redford built. The resort is in a wooded mountain valley surrounded by dramatic snow-covered peaks. The rooms are spaced out throughout the large resort area and there's lots of privacy; all three rooms I've stayed in had views looking out over wooded areas. The rooms themselves are quite luxurious, with many amenities (fireplace, lots of teas and hot cocoa, nice bathtubs, etc) and are decorated in a rustic style; I've never seen rustic decor done so well. The publishers provided most of our food, including taking us out to the two restaurants at the resort. Both were expensive, but the food was some of the best I've had (not that I eat out often, but still); roasted eggplant ravioli, goat cheese and artichoke heart fondue, fried aged feta cheese salad with roasted tomatoes, shrimp-crusted sea bass, and plenty more. There are a lot of nature-oriented activities, including hiking in the summer and skiing in the winter, as well as a spa and some neat-sounding art classes.

If you ever find yourself wanting a room that costs a few hundred dollars a night, look Sundance up. I stayed an extra night on my own dime, and it was well worth it.

I hope to post some pictures up once I get home tonight and can look them over.

Well, off to lecture planning and grading. More later!

Friday, March 05, 2004

Going away pictures

Before I head off to the airport, here are some pictures of the rodents from this week's lab. Enjoy!

rat sniffing

mouse in a cage

The top picture is of a young male rat, the lower picture is of an adult female mouse.

Thursday, March 04, 2004

Donuts, digestion, and rats

This week has been incredibly busy, but also quite fun. In lecture I've started into digestion, probably my favorite topic. Today I did my "donut" lecture, wherein I discuss the different types of digestive systems and compare them with donuts: organisms with no digestive system are a typical bar donut, animals with a gastrovascular cavity (a pouch with only one opening, e.g. sea anemones) are jelly donuts, and most other animals are a typical glazed donut. The students get a kick out of it, and I get to eat the demo after lecture :)

In lab this week we're measuring the metabolic rates of rats and mice. The students can test whatever hypothesis(es) they want, given our equipment limitations, and we've had some pretty neat tests. Body size has been the most popular factor examined, though groups have also looked at the influence of light level, sex, activity, and temperature. We use pet rats and mice, so the animals are tame and most students just let the critters walk onto their hands. The majority of students come out of the lab loving the rats and mice.

I'm heading off to a book publisher's conference tomorrow in Utah, so unfortunately I won't be able to post until next Monday at the earliest. Once I get back from the meeting I hope to find some time to post updates on using the PRS system (summary: it's been going great) and the rodent metabolic rate lab, among other things.

In other news, I'm way behind on grading papers (thanks partially to getting sick last week), but there's nothing unusual about that.

Have a great weekend all!

Wednesday, March 03, 2004

What are you eating?

The Center for Nutrition Policy and Promotion (an agency of the USDA) has a website, the interactive healthy eating index, that allows users to analyze their dietary consumption for a number of factors. After users enter the food they ate on a given day, the site analyzes their diets according to nutrient intake, an overall "healthy eating index," and the food pyramid. It can even track users' consumptions across multiple days.

When I get to digestion in my class, I give students the option of analyzing their diet using the CNPP site as one of their semester projects. The students track their consumption for two days, enter the information onto the website, and then write a report analyzing the healthfulness of their diet. They also have to pick one nutrient that they consumed unhealthfully deficient or excessive levels of, and then use the program to figure out how to change their diet to correct the problem. I haven't had a single student yet who was unable to find a problem nutrient :)

Student reaction to the project is typically ecstatic; many had no idea resources like this were available, and almost all of the papers include comments that they hope to be eating better because of this project.

Tuesday, March 02, 2004

California education bond

Here in California we've just had a statewide election, and on the ballot were a number of budget issues. One was a very large ($12.3 billion) education facilities bond initiative (prop 55). Folks at my campus are hoping it passes since the money will help with a number of delayed projects, including building a new library to replace the one sitting in temporary buildings at the end of our longest parking lot. The LA Times has been reporting that the education bond vote has been close all night, but they just reported these stats (with 51.6% of precincts reporting):
  • Yes: 50.6%
  • No: 49.9%
Um, maybe it's just me, but something seems a bit off with those numbers :)

[update: The bond measure ended up passing 50.7% yes to 49.3% no: see the California Secretary of State's page for more information]

English majors

I recently re-found a clip I love from A Prairie Home Companion. It features a male English major talking with his wife/girlfriend, and it reminds me of Semantic Compositions every time I hear it. Head over to the skit's script and then follow the link at the top of the page to listen to the clip.

SC (and everyone else) should consider this as a late Valentine's Day present. Enjoy!

Monday, March 01, 2004

Labeling dissections

Dissections are an important component of the zoology lab class I teach, as we dissect a number of invertebrates and a rat. Dissection labs I've seen tend to be rather cookbook, with a single student, or group of students, getting an animal and then slowly working their way through it with instructor assistance.

Since each student is often asking the same questions as their classmates, I've been trying to help our lab students use their peers as resources. One technique I've used to encourage inter-group participation in the rat dissection lab is to have each group become an "expert group" that focuses on one specific area of the rat. I prop a large card on each table identifying that group's assigned area, and my student assistants and I go around the room early in lab helping all the expert groups become experts. Near the end of the period each expert group comes up to the front of the room and, using a video camera hooked up to a projector, gives a presentation about their section of the rat.

The expert groups have worked reasonably well; some students in each section consistently tour the room and ask the expert groups appropriate questions. However, students use their "expert" peers as a resource far less during the lab than they use me or my student assistants, and many students never ask another group a single question. The presentations at the end help open everyone up a bit, but by the time the presentations roll around most of the big questions have already been answered. I haven't tried doing the presentations soon after starting the dissection; that might make them more fruitful. Other problems with the presentations are that many structures are very hard to see with our video setup due to the low contrast, and the students aren't always the best presenters (though most do a great job).

One of my student assistants this semester came up with a neat idea to replace the presentations. She suggested providing each expert group with a set of labels (attached to pins) containing all the anatomical terms each expert group is responsible for. Groups would pin these labels to their dissected animals as soon as they found each structure, and after each group completed this task every major item would have a pinned label somewhere in the lab. The pins would provide an immediate, concrete check for the students to see if their ideas are correct (e.g. I could easily see if the rectum was labeled as the uterus), and the labels would provide other students an easy method of finding the location of new structures, motivating students to work with their peers. Once the labeling is complete students could go through the different lab tables to get an idea of where each structure is, and then go back to their rat to continue working, revisiting labeled rats whenever they needed to. The pinning could even be a graded assignment, with each group required to present their pinned animal to the instructor at the end of lab to check their work.

A new blog, new paper, and new job

Lots of new things today:
  • Preposterous Universe is a new science blog, written by a U of Chicago physics professor. Interestingly enough he's currently teaching a course on the history of atheism; it sounds neat. The blog looks great: up it goes on my blogroll!

  • I learned today that my most recent paper has finally gone to print, yay! This paper was based on my thesis work, and man is it wonderful to have it finally done. Phew.

  • Last week while I was out sick I forgot to mention that Semantic Compositions has a new job. In his post he says that he doesn't deserve any congratulations, but those of us "in the know" know otherwise. Congratulations, SC!