Wednesday, September 30, 2009

Not bad news at all

I just found out this news article. Very good news for Texas A&M, but also good news for the whole state. I was usually amazed at the fact that Texas, being the largest state in contiguous US (I had written continental US but Wikipedia told me it included Alaska, :S) would have very few large universities and before the 90s, had only two Nobel prize winners in physics or chemistry. It is not the case anymore and you can see more and more articles being published by places other than Univ. of Texas at Austin, Rice and Texas A&M. A sign that having important people in your department definitely helps.

One good thing about Texas is that it has a lot of money: many texans that made a lot of money and are really proud of their state. Obviously, people like George Mitchell, are really good for science and we need more of them. By the way, this is not the first time it happens for A&M in recent years (Think Dudley Herschbach). The Univ. of Texas at Dallas also got Alan MacDiarmid in 2002. Unfortunately for them, and for science, he died in 2007.

Texas also has its own problems when it comes to science, but so far it has managed to not fall for alternative, non-scientific theories, being put in science curricula. Despite these sour incidents, I think we'll be seeing a lot of investments, like the one by Texas A&M , in the coming years in the state of Texas. I do not own a house anywhere in the US (or the world for that matter) but talking to friends that went to grad school in many different states in the US, the ones that have gone to Texas usually feel they can afford more for the same buck. This will probably help recruit talented young scientists and if donors like Mitchell continue to do their part we'll definitely see a lot of scientific competition coming from Texas.

CORRECTION: Initially I wrote "only one" when referring to the number of Nobel Laureates, in either physics of chemistry,working at a Texas university. I made a mistake and there were actually 2 before the 90s. One is at a medical school and I, wrongly, assumed he won it for medicine. You can see the list of the Nobel laureates currently in the state of Texas. A total of 8.

Friday, September 18, 2009

Bouncing water droplets!!!

I have always liked table-top experiments. In my opinion, those who can come up with those ideas really, and I mean really, understand what they are doing. Plus, they usually come up with nice videos (it's funny, now that I think about it, it is mostly fluid dynamics people that get nice videos. Here's one for example).

In the newest issue of Nature, Howard Stone from Harvard has a reeeeeeeeeally cool result. First, let me show you the experimental setup. The tank consists of water at the bottom and then oil on top. The oil (a poor electrical conductor) and the water are connected to electrodes of opposite sign that provide a high voltage. Once everything is turned on, they manually put a drop of water at the top using a pipette.

Initially, the water droplet is attracted towards the upper electrode by dielectrophoretic forces but when the drop actually comes in contact with the top electrode it acquires a positive charge and then it is repelled towards the bottom (the drop is very small and gravity doesn't really play a role here). You would think that when the droplet moves low enough to touch the water reservoir at the bottom it will just merge and become part of the reservoir. It should do that normally, but in this case it should be even better because the drop is positively charged and the water at the bottom is negatively charged and, as we all know, opposite sign charges attract. What's the big deal? Sounds easy enough,right? Well not quite, what Stone and friends found was that the behavior of the droplet actually depends on the voltage applied between electrodes.

When the voltage is low enough, what I quickly described above will happen. But when the voltage is high enough the result is different. Initially, the positively charged droplet moves toward the negatively charged water at the bottom but when they come in contact (just a tiny contact as you can see here) the water in the reservoir transfer negative charge to the droplet and now they will repel. This means the droplet moves up, towards the positively charged electrode that now is creating an electrical attraction between the two. Eventually the drop will touch the upper electrode and again a charge transfer happens, charging the drop positively and therefore the whole cycle repeats. You can watch a video of this "bouncing" here.

Pretty cool, uh?

Wednesday, September 16, 2009

Hours worked vs. taxes paid

Sean at Cosmic Variance just put up a post on the Laffer Curve. Very interesting concept. But as Sean mentions, who knows whether the assumptions that come into the general Laffer Curve theory or those made by the study referred to in Sean's article are correct.

By reading the comments over at CV, I have a question. If you could keep more of the money you earn i.e. lower taxes, and assuming that you could chose how many hours a day you could work, would you work longer hours to increase your personal income, work the same hours which after all means more income anyways (though not as much as the first option)? or would you work less hours (enough to match your current income)?

Monday, September 14, 2009

Is it good for science?

As a TA I have taught labs and also some discussion sections for the courses. Most of them have been for engineers or science (including pre-med majors) but in one occasion I had to TA for a class designed for liberal arts majors. This was a whole new experience for me, it's not like engineers or science majors other than physics really enjoy taking a physics course (I'll leave my rant about why they should like and learn physics for a later time), but (these) liberal arts majors really, really came into the course hating physics. It didn't help that the professor that was teaching it taught it the exact same way that he teaches plasma physics to his graduate students: by showing lots of math and little explanations into the concepts.

As the semester moved on, my office hours started getting more and more students who looked for a different style and hopefully a chance at passing the course. I should mentioned here that I completely disagree with non-science/engineering majors having the requirement of taking science courses (at least in the traditional way). Don't get me wrong, as a scientist I definitely think the non-scientists also need to know about science, they play an important role in politics, economics and religion (just a few of the areas that heavily affect the funding and spreading of science) but do they really need to know how to solve boring textbook problems in order to appreciate science? I think not. I actually think by forcing non-science majors to take our courses we are doing science a disfavor: not only are they not learning science but they are hating it even more.

I mentioned that traditional science courses for non-majors do not stand very highly in my eyes, but every time I tried to explain my position to someone I ended up getting into many many details that, while true, were so specific many people didn't think they were as bad as I did. A few days ago I found a two-sentence answer that summarizes my view. It was Shinya Inoue who said it during an interview:

"I continue to worry about science being learned as a collection of facts and theories. One needs to have a certain body of knowledge -- but in addition, one needs to understand how the knowledge is acquired-- that really is at the heart of science."

I agree 100% percent. It is a simple phrase that contains important ideas. Just standing in front of a room reciting every equation or theory we can remember is a horrible way of teaching science. Science majors will (hopefully) eventually pick up the lost knowledge, but non-science majors will go through life thinking that science is just a bunch of non-sense stuff.

Is knowing that when we let go of something it will fall that complicated? Really? Can no one do better than integrating the acceleration twice on the board? I hope science professors and teachers soon catch up with the idea that not everyone is as passionate about science as they are and that science is more than just equations and theorems.

Wednesday, September 9, 2009

Nice prevention idea... maybe?

I don't know much (or anything) about regular gatherings of religions except for catholic masses but at least in these ones I see many weak points in terms of disease-spreading prevention. For example, before communion everyone recites Our Father while holding their neighbors' hands. Then they give the peace (shake hands with everyone around them) and a little later the go up for the communion. During communion, the priest puts the Host (sacramental bread) on the parishioners' hands, who then proceed to put it in their mouths. Afterwards, they drink the sacred wine from a common cup that is "cleaned" with a piece of cloth after each person that drinks from it. These are four actions that can spread diseases among the parishioners. With H1N1 flu looking like it is easily transmitted I wonder if churches can still provide the spiritual fulfillment to their people while being proactive as far as infection prevention goes. I am sure it is doable; when the "swine flu" first broke in Mexico, churches there encouraged their attendees not to shake hands and when things got worse they actually closed the churches (or any public gathering for that matter) for some time.

Just this past weekend I was talking to a family member about what churches (specifically in the US) will do to reduce the risk of H1n1 flu spreading among their members and now I find this article. Funny and maybe well intentioned (both because it makes an attempt to stop spreading disease and also because by offering "fortified" wine they might increase the number of people that attend, mmm maybe we should do that in science? ha) but will it actually work? Could they just stop doing that particular thing (drinking the wine from a common cup) for a while? At least while scientists figure out how to best combat H1N1?

I've actually been wanting to post about the real advantage (if any) of alcohol-based hand sanitizers (HS) in preventing getting the flu but I am definitely not an expert in virology or communicable diseases and finding good information on journals/books about this has proven more difficult than I thought so I've put it off. Health agencies, on the other hand, seem to be pretty convinced that using HS on a regular basis (if regular hand-washing is not available) is a good idea. Don't get me wrong, I think Health agencies are really trying their best to prevent any more spreading of diseases but I wonder if their suggestion of using HS is because it actually deactivates the virus or just to people are aware and think before putting their hand in their mouth or nose. You'd be surprised as to how effective not touching your face and covering your sneezes and coughs actually is. I will keep looking and will post about it if I do find out.

In the meantime, we should thank the Swedish for providing us with a great reason (excuse) to drink!

Tuesday, September 8, 2009

Stop the pain!!!!

Some time ago, Savage and I had a talk in which the concept of pain came up. I won't go into the details of the conversation but I will say that at the end we both sort of agreed that pain is a very important issue in human life. I don't think there are many people out there who like pain. And once you start thinking about pain, you start thinking about pain killers (e.g. acetaminophen, ibuprofen, acetylsalicylic acid). Many people are also sort of used to having these pills at hand, after all they are sold over the counter (OTC), but I have a feeling that just a very little number of them actually know how they work. This post is about that, about how they stop the pain.

OTC pain killers fall into a category called Non-Steroidal Anti-Inflammatory Drugs or NSAIDs. Acetaminophen (better known as Tylenol) is usually (and unofficially) considered in this category even though it is not really an anti-inflammatory drug. The main reason is that although it doesn't prevent inflammation, the mechanism of action is somewhat similar to that of ibuprofen (Advil, Motrin) or acetylsalicylic acid (aspirin), or at least that's the assumption. We'll talk about this later and you'll see how little it's known about acetaminophen.

So what is this mechanism? It is the inhibition of a class of enzymes called cyclooxygenase (COX for short). The COX enzymes are involved in the production of prostaglandin and thromboxane. Prostaglandin is the carrier of the message of damage (and the body's reaction is to let you know by creating pain) while thromboxane is involved in clot formation. So, by blocking the COX enzymes, the pain killers make it difficult for the body to know it's hurt and also prevent blood from clotting (this is why in many cases doctors cannot operate on you if you are taking aspirin until your body is free of it).

You can get into more detail and notice that there are several COX enzymes: COX-1, COX-2 and COX-3 and as you can imagine they have different roles. COX-1 is actually a regulator of many physiological processes and serves as a protector of the stomach lining. COX-2 is the one that raises the levels of prostaglandin when there is inflammation of tissue. This is the one that when blocked, produces the wanted effects of pain killers. COX-3 has just recently been discovered and the role is still unknown. Since NSAIDs block COX-1 too, you can now see why ibuprofen or aspirin can cause stomach ulcers, you are basically left without the protective element when you take those pills. Some attempts have been made at developing an specific COX-2 inhibitor and leaving the other ones unaffected but the results have been at least highly controversial, aside from the fact that lab tests show that although specific to COX-2 inhibition these drugs still cause stomach lining damage, the side effects of these new drugs seem to be very serious (think Celebrex or Vioxx).

Ibuprofen blocks both COX-1 and COX-2, while aspirin seems to have a larger effect on COX-1 than COX-2. That is why aspiring "thins" out the blood more than the others. What about acetaminophen?

Well, remember that at the beginning I said acetaminophen was considered an NSAID even though it didn't prevent inflammation? This in turn would indicate that it doesn't block COX-2 and since it doesn't affect blood clotting much then it should mean that COX-1 is also unaffected to a good extend by acetaminophen. So, why is it thrown together with NSAIDs and what the hell does it do to make pain go away? The reason it is put together with NSAIDs is because it seems that acetaminophen also blocks COX enzymes but the real mechanism of action is still debated. Some people argue it is actually COX-3 that is being blocked but the explanations as to how acetaminophen blocks pain without reducing inflammation are still speculative at best. For example, one idea is that acetaminophen cannot do its job in an environment where there is inflammation. This implies that acetaminophen actually in the central nervous system which seems to fit the observed effects. The bottom line is that very little is known about the most popular OTC pain medication.

Also, remember that while pain is awful and one would like to avoid it, overdosing (even just a single time) on NSAIDs or acetaminophen can cause acute liver damage. The chances of surviving this are rather slim so be conscious when consuming these medicines. Just because they work and are sold without much hassle doesn't mean that we understand them well nor that they come with no side effects.