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Saturday, July 31, 2010

Big Business, Little Bugs!

So this week took us WAYYYYYYYY further down the path of science fiction. I've been behind as a correspondent, so sorry for holding out on you.

We did a couple of really fantastic things this week, and also got some excellent swag courtesy of our excellent hosts at the BU Photonics center.

To begin with, we met with several folks from the BU business incubator, which sits on the 6th floor of the Photonics center. The notion, as we learned from David Bergstein of Zoiray Technologies is that small stuff if big business for a lot of reasons. David's company is small right now, and is in the process of trying to pull together venture capital to invest in their product. What was interesting to me was that their technology rests on the same footing as the group I've been working with. As a result, I understood what David was saying - it's all getting a response to very small amounts of certain kinds of chemicals. Those could be a protein if you're trying to detect Alzheimer's disease, or a reaction to an anti-virus if you're testing someone for Marburg. Ultimately, it's got to do with saving lives, and offering cutting edge medical testing to people without lots of money to pay for those tests.

We also heard from Tom Bifano, who is the director of the Photonics Center at BU. In addition to his work at BU, Tom gave us a look inside his own company, Boston Micromachines. Starting, as he said, with "a truly crappy product that really didn't work," Tom and his engineering staff have, several years later, developed an amazing device. The theory is simple: light gets distorted by all sorts of things around us - the atmosphere, water, and the goo in our eyes, to name a few. Where Tom's invention comes in is that it can sense incoming light, and warp the its mirrored surface to correct for these disturbances. The trick of this is that the mirror has thousands of bits that can be controlled by these tiny machines you see above, and that the mirror can change faster than the atmosphere or the goo in your eyes can mess things up.

All you have to do is to check out these two pictures to see why this is a big deal: On the top, we have a normal image of Jupiter taken from a good earth-based telescope. Below, you
see the image taken using Tom's company's adaptive optics. Pretty Amazing, huh?! Check out the link to Tom's company - what they are able to see while looking into your eyeball is pretty astounding!

OK, so back to the title of this week's blog, which said something to do with little bugs. This week, we also got to visit one of my favorite machines. It's such a favorite, that I am going to ask Dr. Hardiman & Dr. Shannon to get me one. I mean, us one - for the science department, of course!!

The SEM stands for scanning electron microscope, and it is quite an amazing machine. As you might have heard, light is a wave, and bends around stuff like all waves do. So, when you go to see really small things, you're in a lot of trouble, because light doesn't make clean shadows or outlines or anything really. Enter the electron: it can act like a wave of course, but when it does, its waves are very tiny, and it is great for seeing very small things.

So, we beat up a mosquito. It was dead long before we sprayed it with gold metal dust to make him show up more clearly on the SEM, so let me reassure you that no mosquitoes were harmed during this demonstration. As you can see, we zoomed down a long, long way.

I always thought those images of housefly eyes were pretty amazing - they still are, but the mosquito seems to have the same kind of
multiple eye-structure feature going on that the housefly does. At least that's what I think based on my limited bug knowledge. Better check with one of the bio people to be sure!

Like I said, I am no expert when it comes to bug parts, but this last image certainly looks like a bunch of cells to me. I have to check with somebody, because I'm really curious to know if we share some of our vision cells with the mosquito. Wikipedia says that the human cone cells can be around 500 nm - 4000 nm in size, so I'm still not sure exactly what I'm seeing here. In a human, the typical cell size is around
10 micro-meters, so maybe those big blueberry things are mosquito vision cells. Like I said, biology is a foreign country to me!

One final thought on that topic: at the end of the week, I again got to sit in on our research group's weekly meeting. Again, I was amazed to see John Connors from the BU Medical Campus explaining the important cell biology to the physics people in the group. That sort of give and take is so common around here - it's not the image of the lone scientist that gets played up in the media at all - it's much more of a team effort. Funnier too! John draws cartoons to show the physics people how a cell works, and the physics people explain to John just how they're going to attack resonances in the chemicals under study. It's pretty hilarious watching them go back and forth!

Wednesday, July 21, 2010

Rocking the Tiny World!

So today was nano-camp day!

Our intrepid group of four (me, Rick, Alex and Nick) have been working to lay the groundwork for this day for a couple of weeks. It was great to finally meet the brave students who had signed up to come to the Photonics center for the day to talk about the science of the very small. Our group of ten students were from all over the Boston area: Brighton, Chelsea, Brookline and Boston itself.
We met the students in the 7th floor chilling area and visited for a while. A number of the students, like Maganow and Yun said that they were considering doing engineering in college. A few said that they were undecided and looking at BU for college. A few were just hoping to do something fun for the day.

That part seemed to work out fine! Professor Altug is about as un-stuffy as you can get - she talked with the kids about what they'd been up to for the past few weeks before introducing them to nano-technology. She started with a version of the Powers of 10.

If you've never played with the powers of 10 applet, you just have to!!! The universe is just an amazing place, and understanding the sizes of the places in it is the key to understanding a lot of other sorts of things. Prof. Altug rapidly took the kids from oak trees to dust mites to bacteria and other gross stuff. Looks nastier on the SEM!

After taking us through the basics of size, she took us through some other examples of nano-tech in modern life. There are more than I would ever have thought possible before starting this little research project. To begin with, quantum dot nano-particles of gold can be engineered so that they can target cancer cells. Because gold is great at turning certain frequencies of light into heat, it's possible to treat cancer using a laser that targets cancerous cells while leaving the healthy ones intact. Another great example from medicine is in the use of nano-particles in labelling cells of various kinds. With new drugs that can slow the spread of Alzheimer's disease, early detection of illnesses is more important than ever. Nanotech is making it possible for doctors to see diseases before they have a chance to get very far. As I've watched Alzheimer's progress in my own dad, I have seen first hand how great these new treatments are. There's still no cure, but this is a big stride forward. There are so many similar stories; different in their science, but the same in that scientists are unlocking the secrets of some of the world's worst killers, here and in the developing world. The hope of so many researchers is that nano-stuff can be made cheaply - cheap enough that doctors in rural Africa will be able to diagnose and treat as accurately as doctors in Danvers, MA.

So with visions of the micro-world burned into our frontal cortices, Nick, Alex and the others led the group up to our lab where we talked through a few important things, especially some pointers on laser safety. The point of our lab was to give students an idea how researchers use light to study the micro-world, and we started out studying some of our micro-samples under the stereo microscope.

At about 200X, you could see what the diffraction gratings were all about - that's actually connected with the real research that our group is doing. It's about a million times more complex, but the idea is the same, just that our group is working at the nano-scale.

After studying the gratings, the kids checked out what they did to light by focusing a green laser on a diffraction grating. Above, you can see Alex taking some readings on the laser beam spread after it's passed through the grating. Based on the wavelength of the light we used, the students were able to figure out the size of the features on the grating. On the left, Yun and Maganow are getting those numbers, while on the right, my partner Rick is helping out one of his students with the calculations.

After lunch, the students mixed up batches of PDMS gel, and coated their diffraction gratings. We put the samples in a vacuum chamber to get rid of the bubbles, which is important because it helps the goo get down into the tiny grooves in the sample. Then we went for a tour, checked out the clean room and some of the other labs around the building.

At the end of the day, the students pulled off their copies, and checked them out using lasers and microscopes. All I can say about this part is that some of them worked well!

The upward bound experience is a long one, and it's a pretty intense six weeks for the kids. They were great to work with though. Who knows if maybe some day they'll be back in that building helping to make some of the discoveries that'll shape their world.

Friday, July 16, 2010

Off to the Clean Room!

This week ended on a definite high note. After lots of not know where to go, and feeling like there was way too much to do, the week ended well. To begin with, our group pulled together some (I hope!) really good materials for NanoCamp. I've posted them over at my Physics 2H page at school, and I plan to use them this year - I think it'll be cool.

Second thing that went right was that we had a good week in the lab. Helen took us back up to the clean room where we got into the extra-clean bunny suits, just like before. She explained that we would be making a negative photoresist on silicon. For those of you who go to concerts and buy t-shirts, it's a lot like screen printing: (That's a link you should follow - it shows you how to screen print.)
Anyway, we did the nasty chemical process last week in making our photomask, and this week got down to business with putting copies of it onto silicon. Helen told us a story along the way that I thought was pretty amazing. Companies like Intel take their people who are the absolute best at spinning silicon disks and trust them with the huge wafers, like that guy is holding up top. She said that if one of those gets dropped, it's thousands of dollars down the drain, and one person banished back to the ordinary clean room. Sad!

We weren't working with any super-expensive units this day, but we did have to be careful. We were spinning 4" silicon disks on the disk spinner (it has a real name but I forgot it.) BTW, you can see how shiny the Silicon discs are - that's John's smiling face reflecting in the wafer that Helen is holding.

Anyway, this part is kind of an art, and it's also a lot different from t-shirt silk screening, too. In putting tiny patterns onto these chips, you can control some of the size of the patterns by controlling the thickness of the photoresist you put on the wafer. And so we have the wafer spinner - works like a carnival spin art machine, except is puts down something like 50-200 micrometers of goo depending on the goo and how you spin it.

After spinning on the photoresist, we baked our wafers in a couple of stages, and then took them to be "screen printed." In reality, we went back to the Suss machine and used our mask to expose our wafers to UV light. Again, wherever we didn't have mask, the photoresisting material gets exposed, cross-links and becomes permanent. Once we wash off the remaining unexposed goo with acetone, we're left with a slick, shiny wafer that has micro-structures cut into it. We looked at our pattern under the microscope, and it looked kind of like this image on the left. This part's beginning to make sense!

Also, what makes me happier is that I can see how what we're doing in the lab fits with what my research group is doing. More on that in the next post, I think!

Friday, July 9, 2010

Reflections for Week Two

Two weeks gone by, and it looks like we're starting to move forward. Here are my responses to the questions we've been given for reflection. Bear in mind that our group is working differently than some others.

What is the hypothesis you are testing?
We aren't testing any hypothesis, unless it was that four unrelated people from very different backgrounds can form a group and crank out good work! Our group is not even doing any research. We are building a product (a series of labs) that will have a definite outcome, so what we're doing is more engineering than science. Good stuff though, but not anything like textbook science.

What kinds of controls does the experiment have?
Hmmmm.... don't know how to answer that at all.

How will you measure your results?
This we can do - we get to run one lab with the high school kids before we use it on the college kids. That's the only measuring we can really do though.

How will the reliability of your data be ensured?
Now this question I like: I think that one thing that has really changed my teaching career has been microsoft word. For me, every thing I try - every test, quiz or homework is a question that I ask the guys in my classes. The key to making things better for the kids isn't to be perfect, it's just to keep on improving, and to use the results you get to see how get there. So the answer to the question is that we record everything. If the folks who come after us want to improve, they can look at our notes and see what we were thinking of. Student tests can be data just as much as lab data can be data. All just facts you're gotta keep track of.

How will inquiry fit into your lesson plan?
This is interesting - we're creating some actual labs, so we might have room to frame the labs to include some inquiry. Definitely, we're putting some puzzles into the program for students to work on, but we're building a product for our professor, who gets to decide just how much inquiry based stuff there will be in there. We'll see!

Group Dynamics: Stuff Hits Fan

OK, so this week took a whole lot of patience. I don't like stepping on people's toes, and I refuse to do it unless there's a really good reason, and I've tried a few other things first. So I didn't. And this is what happened...(not the comic..that's there just for the fun of it.)

(Cartoon courtesly of XKCD. Comix for the engineering minded. Warning - some of them are not totally clean, and some are just dumb. But but but... some are priceless!)
It was absolutely nobody's fault that our group was set up the way it was - we are one high school physics teacher, one middle school science teacher, and two undergrad engineering majors. We're supposed to form a working group that can order equipment, test procedures, and write curriculum for some pretty heavy undergraduate science labs.

To give you an idea of how much of a mess we were, the lab where we were working was a disaster area, but we didn't know to ask before cleaning things up. We all agreed it would be uncool to wreck ("clean up") someone else's experiment without their permission, so I asked three different people for permission and all of them said "I'm not sure... probably it's OK." So I did it anyway. Nobody's yelled yet, so maybe it was OK... or maybe I'll get yelled at next week. Guess I'll find out!

Anyway, at actually producing labs, we were hopeless - we made lots of moves in the direction of working together, but to me, group editing is hard even when you know people well, and you're all on the same page, and we were definitely not. It's not that things ever got unhappy between us, it's just that stuff didn't get done, or followed through on. Soooooo....our professor got pretty unhappy with our group. I suppose I can't blame her - we were not too effective, but like I said, I don't claim to be the boss of anybody, especially when I'm NOT their boss.

Anyway, the upshot of the meeting is that everyone now has very, very clear jobs, which I think will work: Alex and Nick are going to run the test procedures and record how long it takes to do stuff, along with any things they notice. Rick and I are going to do the same thing, and then he and I will write up the step by step procedures. That's the theory anyway...I did find one great source of help in the midst of this though, and that came from Helen. She's so knowledgeable and knows how to get things done. I was stuck in trying to find laser holders - should I try to steal them from another lab? Should I order more? How much money were they? After I got off the phone with her, she called our PI who came down for a visit. In fifteen minutes, I felt like we'd worked out a solution to the whole awkward social arrangement. I was able to find a cheaper solution that what we were thinking, and took charge of ordering stuff from there. We have a lot of work to do and one day to do it on Monday, but at least we're moving in the right direction.

Got a great deal on green and red laser pointers for the lab BTW. I'd tell you where to get them, but then you might poke your eye out with one, and then my kids would go hungry, and that would be bad. Let's just say that I have learned more respect for lasers after our laser safety clinic. They're everywhere around this building, including some class 4 lassers that will slice and dice you if you're not careful. Our lab has class 3B lasers, which are just a notch below in intensity, but still very much worth respecting. If you can make out the graphic, you should probably think "Be serious! I would never shine a laser in my eye!" That's nice to hear, really it is... but what you might not know is that the heavier duty lasers can blind you from light reflected from a.... get this.... a wall. Or a table... or just about anything. There are several levels of safety interlocks that go along with the big lasers - doors, curtains, goggles, key switches - seriously - a lot of thought goes into keeping people safe in these labs.

Thursday, July 8, 2010

One If By Bike

A lot of folks you meet can tell you a story like "A friend of mine knew a guy who got doored riding down Mass Ave - he rolled under a bus and got crushed." That does happen, and is really sobering to consider, but I decided that I just had to take advantage of summer by riding to work. It may still turn out to be a bad idea, but so far it's working out great. Funny thing is - you notice SO much more stuff about the world when you travel through it at bike speed. This one's a photo of the Fellsmere pond in Malden. Looks great, doesn't it? I'll see if I can get some photos of the baby & mama ducks that hang out in it.

It's been a long time since I was able to ride my bike to work, but BU takes their alternate transport seriously - they even have a bike locker in the basement of our building so mah ride can sit safely with its cousins while I'm at work. The thing about riding is that it's 100% engaging. I mean, if you don't pay attention, you'll end up under a bus, like my friend said could happen. These pix are typical. I'm sure that at 2 am, Medford square is beautiful, but right now, I'm just not seeing it. I mean - just how am I supposed to do about those two vehicles on the left? Ride over them?
Now, I know what you're thinking: riding down the street shooting photos from a bike is exactly how you end up under a bus. But NOPE! I realized just after that I took the photo on the right that I might also need my hands for steering. I think this discovery will improve my odds.

Also in my favor is that after Tufts, you get the Cambridge bike paths to help you out. The bike paths for me are a sort of archeological history of people's attitudes towards bike riders. I'll back this up with photo evidence just as soon as I collect it all, but just you wait: there are at least 100 interesting words to be typed on the subject of bike lane symbols. This one's a first generation symbol, near Tufts - that's all I can report for now until I get more photo material, so hang in there.

You've got to hand it to Cambridge though - they are really out there trying to do what's never been done before: to create a bike-friendly American city. One of the innovations that I truly love is the speed table. This one's on Oxford St. between Leslie College and Harvard, and it accomplishes two exciting things: it creates better odds for you at these 50/50 intersections by annoying the drivers (AKA making them slow down), and brings a little bit of mountain bike joy to commuting. Seriously, you can get a little air off the backside of one of these if you hit it right. I know that the police man who was standing directing traffic on the first one of these I hit had to have been impressed.

Once you get to Harvard, you will undoubtedly notice that Harvard Yard sits right in the middle of everything else you might like to get to. Despite the fact that Yard looks like a bike path, I am told that it's really bad form to treat it as such, and that the HUPD will jump on you if you try. Being a basically very respectful rider, I have done the next best thing - using the most direct combination of crosswalks, sidewalks and wrong-way one way streets to get to the other side. Once there though, the ride down DeWolfe lets you out to the promised land: miles of bike paths on either side of the Charles. This pic looks east to the Western Ave bridge - most mornings, I've seen dozens of folks practicing rowing their one person skull boats. I don't know why I never think of the Charles when I think of places to put a boat in, but I've been reminded that it's a beautiful river.

After a few miles of green loveliness, I downshift and ride over the Silber bridge to BU. Towering over the brownstone in the front is the Photonics Center, where our research group is housed. It's an amazing facility - the whole concept of Photonics was new to me when I first arrived here, but it's simple on the surface. The vision that exists in this field is that researchers aim to create the types of discoveries in this century using light that inventors did in the last century using electronics. That means smaller everything, and that the physics of light - both the wave side and the quantum side are being expolited to the max. I can't wait to get to work each day to learn a little bit more - happily, my ride is faster than when I drive!

Tuesday, July 6, 2010

Clean Room, Messy Brain!

Last post, I told you that we were working up lab stuffs for the Upward Bound nanocamp program. Well, in addition to that, I've found out that we are also supposed to test out lab procedures and do writeups for some other experiments. This is actually pretty exciting, because these labs are for the Prof's junior-year course in nanotechnology, and I expect I'll learn a lot more through them. One thing that you've got to check out is the scale of the operations we're talking about here. This applet from FSU is excellent if you want to get a clue about the sizes of things. (The graphic over on the right is viruses at 20,000 magnification - for this week, what you need to know is that you can't get this kind of image using visible light - you just can't!)

Anyway, I've spent time studying some of the labs that University of Wisconsin has built for nanotech education, and they're fairly amazing. Click this link if you want to explore nanotech - the science that's going on here is off the charts interesting. What was neat from a personal standpoint was that our Prof just told us to call up one of her friends at U. Wisc to ask for help - even though people are competitors in her field, it still definitely seems like friendly competition.
The lab we're working on next is this one - to demonstrate how to fabricate nanoparticles, and to show how light interacts with these particles depending on their size. Same as how the blue sky looks blue! OK, so just after we get all of the stuff written and tested for the nanocamp, we can really start to work on these. Whenever that is!

The Clean Room
Today we met Helen who is a project manager and professor at BU. I was so grateful to meet Helen because after spending over a week doing what felt like spinning my wheels, she led all of us on a FUN FIELD TRIP up the clean room. Not only that, despite the fact that Helen is clearly in charge of stuff, she was totally down to earth, and talked with us about her kids, her other research jobs, and the fact that we were elbowing people with real work to do out of the clean room this morning just so they could show us how it works. Like all the rooms and labs in this building, it's governed by key-card access. One look at the photo of my partner, Rick from Diamond Middle School in Lexington, myself and John Walsh from BC High, and you can see why they have key-cards on the place. I think we look like we're ready to go to work at Dunkin's.

Once we were in, and Helen explained what we were going to be doing, we went to the gowning area, where we put on booties, gloves, the gown and the hat they call the "bouffant." Painful. Five minutes later, we were ready for the clean room. Actually, not quite. We were headed for the CLEANER clean room. For this, we had to put on an extra set of high-top booties that came up to our knees, put on extra gloves and then add the stylish burka-like hat to finish off the ensemble. I think I look fantastic - what do you think?

This lab is where graduate students and others build very fine structures onto wafers. These structures could become electronic circuits, diffraction gratings, or, in the case of our group, a base full of nano-holes. What we did was to use a computer-aided machine made by Suss Microtec to write a mask using UV light onto a glass substrate. This is the first step to mass-producing stuff onto a silicon wafter, which we'll do later. Again, the idea is that you can use the short wavelength of UV to cut shapes with a lot of precision into stuff if you pick the materials right. Get it? UV is a smaller wave than blue or red, so it's good to use with small features, just like to see or do anything with the viruses in the top photo, you have to use even tinier waves, like X-rays or electron beams. You might have noticed the slight yellow tint to the right hand photo. Think about it: in a room where UV is used for cutting, you don't want any of those high energy (i.e. blue or purple) colors around. Thus, like you learn in Physics I, if you take away blue from white light, what you get is yellow.
And that seems like a fitting way to end this post, except to point out a few more of my colleagues: that's Helen being professional, Ashley Lagas, who will be rocking middle school in Holliston next year, and John Pinnozotto, who teaches physics in Weymouth, and has the best blog of any of us, by far. If you really want to know what the clean room looks like in detail, check John's blog - I've gotta pull nano-camp stuff together!!

Thursday, July 1, 2010

Settling In...

In settling into a five week visit to a professional research lab, the first feeling that I'll admit to is being totally overwhelmed. The technology that is being used is stacked, layer upon layer to build the machines and devices that are used in research. One thing that all of this technology has in common is that at the Photonics center, it has to do with light.

The second this is that it has to do with building super-small devices, like some of the ones shown here: (in this image, you can see some of the stuff that can be built using the e-beam, or electron beam machine.) Using the e-beam machine, researchers can cut or build tiny structures onto wafers. These structures can do nearly anything depending on what they're built from - they could be holes, like my research group uses, or they could be circuits or diffraction gratings that split light and make it interfere. When you can build down to the scale of a few nanometers, you can build just about anything.

This week, I am doing two things - helping out in designing a lab for a high school nanocamp program which will happen in a couple of weeks, and looking over the shoulders of members of our group as they do some of their work. It's kind of schizophrenic, like I don't have enough time to do anything well, or understand what's going on anywhere. I don't see most of the post-docs or researchers operating like that, and that's a good sign. Maybe we'll get a better grip as the week goes by.

The nanocamp is a week-long program that Prof. Altug is running, and it is open to high school students from all over the country. Here is a little blurb about the program from a BU blog. The program is part of the Boston Public School's Upward Bound program, and we are designing the entire day's program hoping to give the high school kids an honest flavor to the program through our lab and background materials. I was really impressed with Prof. Altug too - I know from listening to her that she will be amazing with high school kids, which is not an ability that just everybody has.

For nanocamp, we are building a lab based around the topic of diffraction. Since the early 1900's, folks have used light to see things that were too tiny to actually seen directly. Since that time, researchers have used diffraction to study crystals, unravel the mystery of DNA's structure, and study counless other chemicals. An entire branch of science, called crystallography, is based on the process of studying scattering. At BU, researchers in the Photonics center are doing things with light that will boggle your mind - controlling it on a level that I never would have thought possible. As I get a clue about this stuff, and how they do it, I'll share as best I can!

Today we're off to the clean room, so we're headed toward the sharper end of the pencil soon!