Procrastinating by returning favors. It's amazing how quickly I help others write/edit, and how slowly I write my own stuff.
9 Dec 2009:
After installing and uninstalling different versions of Aspell no less than 8 times, I finally managed to get the damn thing to work. My most common spelling error? "Desireable" instead of the commonly-accepted "desirable."
Ugh. I thought it really was spelled with 3 e's. And going through my previous publications.. yep. It's all "desireable." Same thing for "monochrometer" vs. "monochromator."
Most common accidental misspelling: "stochiometric" (as opposed to "stoichiometric").
Hm. Apparently my Domain Design software is about 1 year old now. And I completely forgot to tell anyone about it.
15 Oct 2009:
(10:05 this morning)
Cell phone rings, sleepy Sherry goes to pick it up.
(5 seconds later)
Sherry: OMG! There's going to be an earthquake in 10 minutes! Dave, get up and get dressed!
Dave: (groggily) What? No way, people can't predict earthquakes yet..
Sherry: Just do it, hurry, I don't want you to die! I'm going to go outside and see where people are gathering, I'll be back in two minutes.
(2 minutes later, Sherry returns and Dave is somewhat dressed in pajamas)
Dave: This can't be right. There are little kids walking around outside, supervised by the Caltech daycare people. They wouldn't do that in the face of an imminent earthquake.
Sherry: They both called me and left me a text message! They wouldn't do that for no reason, would they!?
Dave: But they didn't call me though... Uh, could I see that text message?
Sherry: Here.
Dave: ... Um, Sherry, you do know what "drill" means, right? It doesn't just refer to an electrical tool..
Sherry: ...
Dave: What did they say in the phone call? They must have mentioned "drill" or "mock" or "simulation" or something to that effect.
Sherry: (slightly embarrassed) Actually, I heard "earthquake" and kind of stopped listening to the message before it ended.
(In Sherry's defense, her mother was almost killed in the 1976 Tangshan earthquake, so Sherry has reason to be scared by earthquakes.)
9 Oct 2009:
Obama just won the Nobel Peace Prize, the same prize Mikhail Gorbachev won in October 1990, fourteen months before the Soviet Union collapsed. Part of me wants to laugh, and part of me is really, really scared.
11 Sep 2009:
A general-audience summary of my upcoming research:
Cancer, as a family of diseases, distinguishes itself from other leading causes of death in that it cannot be reliably prevented or cured. This arises from the nature of cancer: cancer is, at its heart, like a virus in that it replicates endlessly, and is not a localized problem. Unlike viruses, however, cancer cells derive from the body’s own cells. The body’s immune system, normally so efficient at containing and eliminating bacterial and viral threats, are powerless to stop cancer because cancer is not a foreign invader, but rather an internal rebellion.
Cancer treatments face the same difficulties as the body’s immune system: cancer therapeutics must eliminate or inoculate cancer cells without harming the majority of the body’s healthy cells. Many currently offered treatments, such as cisplatin, possess significant side effects because they do not specifically target cancer cells, and thus cannot be used as a systemic treatment for metastasized cancer.
If the key to developing a robust systemic anti-cancer therapeutic is specificity, then what separates cancer cells from healthy cells? While the reproductive ability of cancer is its most defining feature, it is not unique to cancer cells. For example, epithelial cells such as skin cells and stomach lining cells also divide regularly and rapidly. Consequently, it is not a good idea to target cells that reproduce—another triage method is needed.
MicroRNAs are short fragments of RNA that serve regulatory roles within the cell. The expression patterns of different microRNAs vary from cell to cell depending not only on the cell type (i.e. brain vs. liver), but also on its state (i.e. healthy vs. cancerous vs. virus-infected). Thus, microRNAs can serve as a molecular signature for cells within an individual and is an essential part of next-generation cancer drugs. Unfortunately, standard techniques for analyzing microRNA quantities in the test tube involve fixing or lysing cells followed by quantitative PCR techniques.. all harsh techniques that necessarily kill the cell from which the microRNA derives. This is acceptable for studies in the test tube, but not for actual therapeutics in the human body.
The proposed research seeks to develop nanoparticle-based cancer therapeutics with embedded microRNA sensing and logic. In essence, each therapeutic nanoparticle has a tiny onboard “DNA computer” that figures out if the cell it entered is a cancer cell by interacting with the nearby microRNAs, and releases its therapeutic cargo only in cancer cells. This approach is significantly more complicated than many other cancer treatment approaches, but benefits in being vastly more generalizable. Every additional research result characterizing another microRNA provides another cancer marker to analyze in real time. Furthermore, unlike treatments based on small molecule chemistry, there is little risk of cancer cells developing resistance, because the nanoparticles can be easily reprogrammed.
4 Sep 2009:
E for Effort
Most American schools use the A through F grading system, with a conspicuous lack of an E letter grade. This probably should be corrected, and reserved for students who supposedly gave "effort" but yielded no results. The problem is, instead of putting the missing E grade where it's supposed to be (that is, between D and F), the expectation of most now is that effort should be sufficient for a B or a C (or an A, if you're at Harvard). This is not so much of a problem if it was limited to academia, but unfortunately, people take this perspective into the real world.
The most striking examples of this in recent times are the string of bailouts: the banks, then the insurance companies, and then the automobile manufacturers. Modern economics is based on the idea of competitive advantage: if Japan can make cars better and cheaper than the U.S., and the U.S. can make medicines better and cheaper than Japan, then it's in the best interest of both to specialize and trade. So the United States should give up the auto industry if it's not good at it.
But the problem deeper than that. Why are the U.S. auto industries not competitive? Because of the workers' unions (specifically the United Auto Workers union, in the case of the auto industry). Unions started forming in response to the appalling conditions of the 1920's laissez-faire business approach, which yielded conditions that inspired Upton Sinclair's "The Jungle." Unions sought to protect the workers from being exploited by powerful businesses, which was a legitimate concern back in those days. But not anymore.
There are two problems with the "effort should be rewarded" philosophy. First, it is difficult to measure the intangible "effort." A person who "works" long hours may in fact be using his workplace's free high-speed Internet afterhours for listening to music. A salesman who travels everywhere hounding potential customers may in fact just like to travel. Even for those whose jobs have a tangible product, such as a worker making widgets, it is difficult to tell the worker's maximum productivity were he truly using his maximum effort.
Second, there are competitive advantages among individual humans too. A widget-maker who produces fewer widgets per day than his peers shouldn't be incentivized to keep making widgets--he should be encouraged to find and put to use his real talents, be it waiting tables or writing or teaching yoga. At the end of the day, rewarding effort, rather than results, yields an unhappier and less productive populace.
On a completely separate note, I generally support the death penalty. But stories like this (which is very well written, by the way), always make me think about what's theoretically good for society and what's practically good for society.
The politics game
In American politics today, there are two significant parties (R and D) and a tiny sliver of Independents(I). One or the other of the two major parties usually has control, but not enough of one to override a filibuster in the Senate. In polarizing issue such as health cares, the parties tend to vote as a block, and thus, one can analyze their actions and consequences from a tractable game-theoretic approach. Consider the following matrix of payoffs:
R malleable
R adamant
D malleable
(4, 4)
(0, 10)
D adamant
(10, 0)
(-5, -5)
The first score in the pair is what the Dems get in each scenario, the latter is what the Reps get.
The first thing to note is that this is NOT the prisoner's dilemma: In the prisoner's dilemma, it is better for a prisoner to defect, given that the other prisoner has defected.
In the game of politics, both parties badly want *something* to be passed, lest the image of themselves become even worse in the eyes of the public. But they have sharply different views on what that something should be.
Basically, this game usually plays out as a staring competition. For the first N rounds, both sides are adamant, until one side finally breaks, unable to take any more of the negative payoffs that standoffs cause.
The exact values of the payoffs in the mutually adamant (standoff) case are vital for deciding the outcome of the repeated game.
If one party stands to lose more with every moment of inaction, then they will be the party that finally caves.
Historically, in American politics, inaction favors the out-of-power party. Which is why I'm predicting that Obama will drop the public option in his speech next week (or at least equivocate about it, as typical) .
3 Sep 2009:
I'm increasingly alarmed by the liberal reaction to.. well, just about anything in recent days. But specifically today, I'm upset at their knee-jerk reaction to the investment banking compensations debacles. Yes, I'm just as outraged that socially unproductive Goldman Sachs investment bankers can take home tens of millions of dollars a year, and more than anyone, I'm distraught by the social misallocation of intelligence.
But raising income tax to punish the investment bankers is like.. decapitating anyone taller than 6'2" because some people wear stilts and heels. Consider that the average specialized surgeon needs to go through 4 years of undergraduate education, 4 years of medical school, and 9 years of residency and fellowship before finally landing his $300k a year job. I have no problems at all with that salary, and I think it's downright irresponsible to substantially increase the surgeon's tax burden in order to "punish" investment bankers or to "spread the wealth" around by providing health care for America's 12 million illegal immigrants.
And, most importantly, this solution does absolutely NOTHING to address the main tragedy: the misallocation of talent. By most standards, the investment bankers who are the most highly compensated are generally bright people--they usually have degrees in hard physical sciences from top universities, and have floated up the pay charts because they performed well. Yet they are all embroiled in one massive zero-sum game that is the stock market. Making money from dynamic arbitrage doesn't create any tangible product or service, and does not even offer the remote possibility of improving the lives of U.S. citizens. So more than anything else, government regulations and laws should aim to redress this employment inequity. Increasing income taxes across the board will do nothing to redistribute talent, because there is a dominance problem: a higher salary before taxes always equates to a higher salary after taxes.
What this means is that the right approach is to cut down on the profitability of hedge funds and investment banks. Now, the liberals would approach this problem with increasingly arcane tax codes, but I think the right way to do this is to have a government-run hedge fund that competes with the rest. Call it the "financial public option." With the full weight of the United States economic might, the public financial firm should be able to sharply limit the profitability of gaming the stock market... provided that the public financial firm actually has talent comparable to those of the private firms.
And that, of course, isn't going to happen, for the same reason that a health care "public option" wouldn't save any money: Efficiency and competitiveness require high compensations, increased autonomy, and merit-based compensation for government employees... all of which have been expressly prohibited.
2 Sep 2009:
Blasphemy
I don't buy Al Gore's argument about global warming.
I'm not denying the rise of carbon dioxide levels nor the shrinking of the Greenland ice caps, but rather I'm disputing that the only solution is to cut back on conventional energy and to switch to "clean" energy.
There are really three facets to this argument: (1) it can't be done, (2) people won't do it, and (3) there are (many) other ways.
First, it can't be done. Not to disparage scientists like Nate Lewis or visionaries like Ray Kurzweil, but if you believe Al Gore's doomsday predictions, we have roughly 5 years to develop a new cheap and clean source of energy, and another 5 years to implement it broadly across the world. I'm less certain of the impossibility of the first than I am of that of the second. The Wright brothers demonstrated flight in 1903, but it would be the 1960's before flight would be used broadly and commercially (as in, available to maybe 5% of the population). Television was demonstrated in 1926 and it wasn't until 1947 that the regularly-scheduled TV programs started appearing. Given the huge gaps in technology dividing various parts of the United States, let alone the world, I highly doubt implementing of *any* technology worldwide can be accomplished in less than a decade, by which time the world has already irrevocably gone "over the edge," if you're to believe Gore.
Second, people won't do it. Whatever advances technology provides in the form of efficient solar cells, it will be many, many years before they're cheaper than energy from coal, natural gas, and oil. Carbon dioxide emissions are a negative externality, a cost not paid by the consumer, and thus there will always be defections so long as there are no alternatives that are cheaper. Government incentives could marginally help the adoption of new technology in America or Europe, but asking the rest of the world to go along is probably as hard as asking the rest of the world to buy Fannie Mae and Freddie Mac stocks en masse. And if you think the United States can get 100% compliance with clean energy laws even domestically, then I ask you to read about the growth of marijuana in Sequoia National Forest.
Third and most importantly, there are other ways. From space sunshades to ocean wave pumps to atmospheric sulfur injections. One may argue that these "hacks" introduce other problems, but I appreciate the veracity of the saying, "Necessity is the mother of invention." As another bonus, these (and other) methods are available now, and mass scale production could be exactly the stimulation the economy needs.
28 Aug 2009:
You know, I relearned a valuable lesson today: Don't be cheap. Installing Windows XP on my Mac with Apple's Boot Camp took three days and it was a nightmare to move files around. With Parallels, at $80, I save myself a lot of pain. (Installation only took about an hour, and file sharing is seamless.)
14 Aug 2009:
If OSes were anime girls:
10 Aug 2009:
Oy. NIH forms are, by far, *the* most unintuitive and confounding in the world.
25 July 2009:
Research proposal has a size limitation equal to 5 single-spaced pages with one-half inch (0.5) margins on all four sides of the paper (this page limit includes figures and references). Use 12-point Times New Roman or 11-point Arial as the minimum font size for the text of the proposal. You may use 10-point Times New Roman or 9-point Arial font type for the figure legends, tables and reference list. Upload this file in pdf format. The style/presentation of the proposal is determined by the applicant, not LSRF.
But they didn't say anything about the line spacing!
20 July 2009:
Woohoo! Yay for postdoc applications not requiring transcripts :)
Whew. Two down, two more to go (this year).
No, I mean postdoc applications, not papers. Papers are still sitting at 0 down, 7 more to go.
19 July 2009:
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I feel ambivalent about this. On one hand, I think it's kind of romantic and maybe even rational, even their ages and health states. On the other hand, they violated every ounce of my personal philosophy of never giving up. This reminds me a little of Daniel Gilbert's book, "Stumbling on Happiness."
8 Jul 2009:
So, I needed to optimize energy parameters for best fit to one of my catalytic systems. I write up my error function and pipe it through to fminunc in Matlab and let it run. Error score initially was 99.8, and after running the optimizing for about 2 hours, Matlab gave me parameters that yielded error score of around 40.
But the fit looked terrible, so I fitted the parameters by hand for about 20 minutes, and got the score down to about 25. At this point, I decided to have me a little race. I fed in though parameters as the new initial condition, and had Matlab optimize it with fminunc while I did my manual optimization. About 20 minutes later, Matlab decreased the error score to 24, while I got it down to 12.
I was pretty sleepy by then, so I fed my new parameters to Matlab and went to sleep for about 3 hours. I woke up and checked up my on Matlab.. it was still optimizing, and it had achieved parameters that yield an error score of.. 40. >_<
2 Jul 2009:
Reminiscences of academic close-mindedness
So, Caltech is a pretty good place. People are generally smart, there are a lot of scientific resources, and people are usually receptive to at least considering ideas that seem crazy initially. However, even at Caltech, the last is not always the case. So I'll share two stories from my Caltech undergrad days.
The first one takes place before I was even officially a Caltech undergrad. I started early in the summer of 2000 to do optics research as part of the Axline program, and it was during then that I took the Caltech placement exams for placing out of introductory classes in math, physics, and chemistry. In the math exam, there were about 6 questions, and most of them were relatively standard calculus questions. There was one that was interesting though; it went like this:
Four ants start at the four vertices of a unit square. Each ant moves towards its right neighbor with equal speed, and so the ants spiral inward until they meet in the center. What distance do they travel before they meet?
I think the intended solution was set up parametric differential equations, but I figured, because of symmetry, the positions of the ants always formed a square around (0.5, 0.5). Travelling directly from (0, 0) to (0.5, 0.5) is distance sqrt(2)/2. However, the ants always travel at a 45 degree from the vector to (0.5, 0.5), for every 1 unit that they travel, only sqrt(2)/2 of it is inward. Thus, they travel exact 1 unit of distance before they meet in the middle.
Math ended up being the only course I didn't place out of.
The second was during my freshman year at Caltech, during a Theory of Computation class. One of the problems on the homework set was, show that there exists a bijection between N (natural numbers) and (N,N) (ordered pair of natural numbers).
The solution we learned in class is to do a diagonalization. Ordered pair (m,n) is the (m+1)th point on the (m+n+1)th line, and is mapped to (m+n+1)*(m+n+2)/2 + (m+1). But that formula was hard to remember and I wanted to do something original. So I did this bijection:
Take an ordered pair (m,n), and create a new number that alternates the digits in m and n. That is, (25, 36) turns into 2356. This can be written as pseudocode as:
for (i = 0; i < MAX; i++)
x += pow(10,2*i) * ((m / pow(10,i))%10);
end
for (i = 0; i < MAX; i++)
x += pow(10,2*i+1) * ((n / pow(10,i))%10);
end
I got a 0 on that homework problem; the TA didn't get my solution >_<
1 Jul 2009:
Thought of the Day:
Pre-cast gels, like lotteries, are a form of the idiot tax. We need more of these.
