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Tuesday, November 18, 2014

Why We Need to Study Comets

News wires are full of stories today about the detection of organic molecules by the comet lander Philae. The more exciting news, arguably, is that Rosetta scientists are "very confident" Philae will wake up again as the comet gets closer to the sun. It should be noted that in October, Rosetta had already detected formaldehyde (an organic compound), sulfur dioxide, and hydrogen sulfide (which is nasty-smelling stuff, and quite chemically reactive), plus carbon monoxide and carbon dioixide, in the comet's vicinity.

How excited should we be about finding organic molecules on comet 67P/Churyumov-Gerasimenko? It's hard to know, actually, until the identities and abundances of the organic molecules are determined in greater detail, but we should bear in mind that the finding of organic molecules in space rocks is nothing new. That's not to say it's not exciting, though. It always is, IMHO.

Hydrocarbons are actually surprisingly abundant in space. The majority of stars in the Milky Way (and possibly elsewhere) are red and brown stars, including many brown dwarfs that are so cool (think room temperature) you wonder why they qualify as stars. Many of the brown dwarfs, in turn, are super-rich in methane (the simplest of hydrocarbons).

Carbon chemistry is amazingly complex in meteors. (For a great overview, I recommend the 2002 paper by Mark A. Sephton.) Only about 5% of meteorites are iron meteorites (and that percentage is probably greatly inflated by discovery error). Most of the rest are carbonaceous chondrites.

The Murchison meteorite is among the best-studied meteorites and shows monocarboxylic acids at 332 parts per million; amino acids at a concentration of about 60 ppm; sugar-related compounds at 60 ppm; urea at 25 ppm; alcohols, aldehydes, and ketones at 11 to 16 ppm each; purines at 1.2 ppm; pyrimidines (uracil and thymine) at 0.06 ppm; and a zoo of other minority constituents. The fact that many of the amino acids discovered in meteorites do not occur in proteins has been taken as evidence of an abiotic source chemistry. Also, the fact that the meteors' chiral amino acids tend to occur in racemic mixtures (with no enantiomeric excess of L- over D-forms) has been taken as evidence of abiotic chemistry, although this view should be tempered by the finding that on earth, D-enantiomers in natural sediments tend to increase in concentration with the age of the sediment. (In other words, as sediments age, natural racemization tends to even out the ratios of D- and L- amino acids.) Also, it should be noted that enantiomeric excess has, in fact, been observed for some meteorite amino acids. The presence of enantiomeric excesses of various kinds in various amino acids from various meteorites, and the possible reasons for those excesses, are still a matter of contentious debate. (See Sephton's paper for details.)

What's perhaps just as interesting (or more interesting) than the finding of amino acids in meteorites is the fact that much of the organic matter in carbonaceous chondrites is tied up in high-molecular-weight insolubles. Thus, the controversy over amino acids and their stereochemistry is somewhat like trying to understand the architecture of a house by analyzing the mortar holding together the bricks.

Aromatic compounds detected in Cold Bokkeveld and Murchison meteorites
using thermal degradation plus gas chromatography and mass spectrometry.
We know relatively little about the higher-molecular-weight components of carbonaceous meteorites. Sephton notes, however: "The majority of the carbon in meteoritic macromolecular materials is present within aromatic ring systems." Indeed, many species of aromatics have been recovered from meteorites using thermal degradation (pyroloysis).

Where do all these compounds come from? We know that interstellar clouds contain methane, formaldehyde, water, molecular nitrogen, and ammonia. These molecules are known to condense around dust grains (and comets), but there's also a lot of UV light, ionizing radiation, and heat in environments like the early solar system; and these could have led to a lot of chemistry. Studying comet 67P/Churyumov-Gerasimenko should tell us more about all this, which in turn could help us understand how life arose on earth. We know that every day, something like a million kilograms of extraterrestrial material rains down on earth. The fall-rate was probably much higher, early in earth's history. It's not inconceivable that 10% or more of the biomass on earth got its carbon from "somewhere else." (See the final paragraph of Sephton's paper.) Arrival of complex hydrocarbons from meteors, asteroids, and comets may well have jumpstarted life on earth. This isn't the only reason to study comets, but for me, it's one of the most compelling.

Saturday, November 01, 2014

A Virus Where It Shouldn't Be

Words like "bizarre" and "unexpected" hardly suffice when describing the results published this week in PNAS (one of the most respected journals in all of science) by Robert H. Yolken and 17 coworkers from Johns Hopkins, University of Nebraska, and Baltimore's Sheppard Pratt Health System, who wrote about finding a peculiar virus in the noses of a number of individuals. The virus they found (through DNA metagenome analysis) was something called ATCV-1, a large DNA virus normally associated with the freshwater alga Chlorella.

ATCV-1 virions attached to a Chlorella cell.
Just to bring you up-to-date quickly: The scientists in question stumbled onto the fact that DNA from the ATCV-1 virus appears to exist in the noses and throats of a surprising fraction (43%) of randomly chosen individuals. The study population of 92 people is not large, however, and we should not be too quick to jump to conclusions. Nevertheless, the mere finding of this virus's DNA in that many people's noses is shocking, because this is a virus that, until now, was thought to occur only in algae, not higher life forms (and certainly not in humans).

To understand how shocking this is, you have to realize that viruses are generally extremely highly adapted to specific hosts. A virus that attacks tobacco plants only attacks tobacco plants. A virus that infects bacteria only infects bacteria, and generally only a specific species of bacterium. Viruses coevolve very closely with their hosts, developing extremely intricate, fine-tuned adaptations to a specific organism. For a virus to cross species lines (let alone Kingdoms) is unusual, to say the least. And thank goodness! Otherwise, you might come down with pox from an insect bite, or get any number of deadly diseases from eating ordinary foods.

As it turns out, ATCV-1 (Acanthocystis turfacea Chlorella virus) has appeared in this blog once before, back in March, in a post I did called "A Virus, a Worm, and a Louse Walk into a Bar." The point of that post (ironically) was to show that while most virus genes tend to have a great deal of DNA homology with their host counterparts, the genes of certain algae viruses actually appear to have greater homology with genes in the human body louse. Which perhaps should have been a tipoff, of sorts, to the Yolken et al. findings. Certainly, it adds more color to the story, knowing (as we do) that phycodnavirus DNA may have have crossed species lines before. ("Phycodnavirus" is the name scientists have given to the family of large DNA viruses that infect algae.)

What do we know about ATCV-1? It's fairly large, as viruses go, with a genome of 288,047 base pairs, encompasssing as many as 860 genes. The fact that the genome has been fully sequenced doesn't mean we know how it works, though. In fact, we don't know what most of the 860 genes do. Some of the genes are (as in many king-size viruses) devoted to DNA-synthesis functions of a type commonly associated with nuclear-expressed genes in the host, meaning that the virus appears well adapted to take over the nucleus of a cell. This is not always the case; some viruses are adapted to thrive in the cytoplasm, away from the nucleus.

Intriguingly, the Yolken group conducted tests of cognitive function among enrollees in its study and found that there was a statistically significant reduction in cognitive ability (on the particular measures tested) in the group of people that tested positive for ATCV-1. To determine if this was just a fluke, researchers evaluated the effects of the virus on mice. As it happens, inoculated rodents showed deficits in recognition memory and attention while navigating mazes. In other words, exposure to the virus is associated with cognitive deficits in both humans and an animal model.

This is remarkable, since (if true) it would suggest that the virus traveled through the blood (of humans and mice), crossed the blood-brain barrier, gained entry to brain cells, and expressed its DNA inside brain cells (a type of cell the virus would presumably never encounter in its normal habitat of freshwater marshes and lakes). It all sounds (and is) very unlikely. But there you are: PNAS is one of the most esteemed science journals in the world. They published the result. It's as real as can be.

Of course, the work needs to be replicated and extended. And I'm sure it will be.

And I think what we'll find is that phycodnaviruses have been crossing species boundaries for some time. If you go back to my original blog about this, you'll see an example of a particular gene, encoding a ribonucleoside reductase, in another Chlorella virus (called PBCV-1), which shows greater homology to the ribonucleoside reductase of the human body louse than to the same gene in the virus's "normal" host, Chlorella. (The homology between PBCV-1 and louse reductases is 53%, versus 48% for virus and Chlorella. These are protein-sequence homology numbers.)

If we check the ATCV-1 reductase for homology with reductases in other organisms, we find that the highest scoring non-viral match (53%) occurs not with Chlorella (the virus's host), but with Lichtheimia corymbifera, a fungus found in soil and decaying plant matter. Interestingly, this fungus is known to cause pulmonary, CNS, and rhinocerebral infection in animals and humans. (But there is no known association whatsoever between ATCV-1 and the fungus.) One wonders whether the fungus has learned a few tricks from marine viruses; or perhaps vice versa?

If you're wondering how the people in the Yolken et al. study could have come in contact with ATCV-1, maybe the answer is as simple as taking a drink of water from a mountain stream, or drinking unfiltered water from a well, or swimming in a lake, or perhaps just walking in a marsh.

Suffice it to say, a good deal more remains to be learned regarding the ecology and life cycles of the phycodnaviruses, and cross-species infection/transfection generally. I feel certain the recent results of Yolken et al. will stimulate a great amount of much-needed followup research.

In the meantime, would you grab me a bottled water?

Please share this story on your favorite social channel, if you enjoyed it. Thanks!

Friday, October 31, 2014

An Amazon Lesson

I wrote a week ago about how I made 57% on my money overnight when Amazon stock crashed. It's time to add a footnote.

My strategy of buying put options (ahead of the earnings announcement) was to protect my actual shares; and it worked. But what about the shares themselves? They went down in value by around 10% on October 24. Most (amateur) investors, after seeing their shares go down 10% overnight, will panic-sell and "take their lumps." That's seldom a good strategy, however. If you liked something at $314, why would it not be even more attractive at $285?

The morning of the Amazon stock crash, I bought more shares immediately.

In the intervening time, Amazon has gone from $285 (just a week ago!) to $302 this morning. Buying more shares turned out to be exactly the right thing to do.

The moral is: If you believe in a stock, buy more of it when the price goes down. Don't panic-sell at a loss.

Will Amazon keep going up from here? No one can know that, of course. But I think six months from now, Amazon will not be under $300, any more than AAPL will be under $100.

Why buy AMZN at all if the company shows no profit? Because free cash flow is still growing. The only thing that could take Amazon seriously lower ($50 a share, say) would be a major health event that causes Mr. Bezos to leave the company unexpectedly. If Bezos ever leaves, I expect there will be a very short-lived dip in the stock price. You should buy that dip. Any subsequent management team will be perceived (rightly or wrongly) as "more responsible" and more likely to force profits to the bottom line than Mr Bezos. And that will take the share price sky-high.

Bear in mind, Bezos could make Amazon profitable overnight, any time he chooses, just by "turning a few knobs." But doing so will interrupt the company's growth. Right now, he chooses growth.

That's worked very, very well so far.

Tuesday, October 28, 2014

Making Money from Twitter

A few days ago, I blogged about how I made money from the recent sharp drop in Amazon's stock price. Well, I repeated the trick (to the tune of a 62% overnight net gain) with Twitter. Except this time, it wasn't a hedge but an all-out bare-naked bearish bet. I sold what few Twitter shares I owned a few hours prior to the earnings announcement, then doubled up on December $50-strike put options. The options were up very sharply today, of course. (Twitter stock went down 11% overnight.)

Things always look clear in retrospect. But I must say, in retrospect, it was, in fact, a pretty safe bet (going into last night's announcement) that Twitter stock would go down. The only question was by how much.

I had studied the previous quarter's results. What I learned is that Twitter is pretty far from turning a profit. Had Twitter announced a $400M quarterly top line, last night, with expenses held to the same as last quarter's expenses, the company would have broken even. I think we all knew they were not going to turn in a $400M top-line number. The critical question would turn out to be: How are enrollment numbers looking? Is the user base growing? And: With advertising starting to appear in timelines, are people still as engaged as ever?

On the latter question, the answer seems to be no. Monthly timeline views (on a per-user basis) are actually down 7%.

Twitter has a big problem, which is that its user numbers are inflated and most users are not active. Twitter claims to have something like 284 million monthly active users, but a recent report by an independent analyst firm (Twopcharts) shows that only 126 million Twitter users have tweeted in the last 30 days.

Twitter's CEO was on CNBC last night trying to defend the large number of "non-logged-in" users on Twitter (lurkers who come just to view World Series news or whatever). He actually maintained that such users are valuable to advertisers. Which is kind of like saying people who dig old magazines out of barber-shop trash bins are valuable to advertisers. It was hilarious.

I don't want to rehash Twitter's numbers endlessly. For the best article on the recent earnings report, I recommend this top-notch Forbes piece by Chuck Jones.

Bottom line, what prompted me to buy puts ahead of yesterday's earnings announcement were these factors:

1. Twitter user numbers are inflated.
2. Twitter is very far from break-even on its financials.
3. The potential for an upside surprise in the earnings report had to be considered extremely small.
4. The $50 early-October valuation for the stock was/is based on hype, not solid financials.

The fourth factor finally convinced me to get rid of all Twitter shares and buy naked puts. That decision turned out to be correct.

Friday, October 24, 2014

How I Made 57% Overnight When Amazon Stock Got Crushed

DISCLAIMER: I am not an investment advisor. Before entering into any trading strategy based on anything presented here, consult a qualified professional (or better yet, half a dozen of them). This post is meant to be educational, not advisory.

With that out of the way, let me explain an investment tactic I have sometimes used with great results. None of this will be news to an experienced investor. It will be news to some.

Going into last night's Amazon earnings report, I was holding some shares of Amazon (accumulated during the big market down-move of earlier this month). Naturally, I wanted to protect those shares against a sudden price drop like the one that happened after the previoous earnings report, 90 days ago.

I bought put options (a bearish bet) late in the day yesterday, fearing that a bad report from Amazon would move the stock lower. Just to review: A put is a contract that gives you the right to sell a particular stock at a predetermined price (the so-called strike price) during a particular time frame. I bought the December AMZN put, strike price $295, yesterday afternoon when the stock was trading around $314. The $295 strike means the put was $19 "out of the money." Because it was so far out of the money, the put was relatively inexpensive, at $8.99 (times 100 shares: $899, plus commission, per contract).

Last night, after Amazon announced its $437 million loss (95 cents a share; much more than the 74 cent loss the Street was expecting), the stock price fell sharply. It opened this morning down $30, at $284. (It rebounded to $290 within a few minutes.)

My put contract went from being $19 out-of-the-money to $5 in-the-money. Its price rose from $8.99 to $14.28, a 57% overnight gain.


Taking a naked short position is risky, but in reality I was using the put to protect shares of the actual stock. (It was a hedge, in other words.)

This same hedigng tactic paid off handsomely for me three months ago, at the last Amazon earnings call, which also moved the stock down about $30 a share.

Will it happen again? No one knows. But we do know that earnings announcements often cause sudden dramatic moves in stock prices, particularly with tech stocks.

Options are not for every investor. They decay in price (quite rapidly) over time, they're subject to huge price moves, and if you're not careful you can lose part or all of your money. If you decide to look into options, educate yourself thoroughly on the risks. The risks can be substantial. But so can the rewards.


Monday, October 20, 2014

Grab Twitter Names from a Web Page

I've been remiss in not posting more often here. Been carried away curating news for my Twitter account. But speaking of which: I want to share a hack with you (please stay with me here even if you're not a coder) for getting a list of Twitter names from a web page. This is a really quick and dirty hack, but also relatively easy. I encourage you, even if you are not a coder, to try this simple experiment. Ready?

First, go to a Twitter window or tab, preferably the one at https://twitter.com/i/notifications.

In Chrome, type Command-Shift-J. (Firefox: Shift-F4.) That will make a console window appear.

Now Copy and Paste the code shown below into the console window.

m = document.body.textContent.match( /@[_a-zA-Z0-9]+/g);
lut={}; 
for (i=0;i<m.length;i++) lut[ m[i] ]=1; // undupe
r=[]; for (k in lut) r.push(k);
r.sort().join('\n');
 
Okay. In Chrome, you execute the code by hitting Enter. In Firefox's Scratchpad you'll need to do Control-L. In either case, executing the code should cause Twitter names (like @kasthomas) to appear in an alphabetized list, inside the console.

Now you can cut and paste those names as desired, to do with as you please.

Note: The code indiscriminately grabs all Twitter names on the page. It doesn't attempt to do anything special like just grab names of people who Retweeted you. (Left as an exercise for the reader.)

I often use this trick to harvest names of people to gang-thank in a Tweet. (On Fridays, I tend to thank a lot of people for using the #FF hashtag on me.)

Try it.

Code explanation: The first line uses a regular expression to match names of the form @letters_or_numbers. The second line creates a lookup table (with the clever name lut). The third line stuffs names into the table. Doing this, in this particular fashion, has the side effect of unduplicating the names.

The fourth line creates an array and stuffs the names into it.

The fifth and final line sorts the array and prints it to the console, one name to a line.

Ain't pretty. Kinda fugly. But it works, right?

Thursday, October 16, 2014

Can Apple Win Back Market Share from Android?

Android has roughly 70% market share in most countries. Apple hovers around 30%. What's the outlook for Apple? Can it hope to make a dent in Android's overdog status? Can it hope to reverse a longstanding trend toward Android dominance?

I think it can, and will, starting early in 2015.

Apple has announced its newest smartphones will ship in 36 more countries by the end of October, and the company is on track to be in 115 countries by the end of the year.

New markets (and rollout dates) for iOS include:
  • October 17: China, India and Monaco
  • October 23: Israel
  • October 24: Czech Republic, French West Indies, Greenland, Malta, Poland, Reunion Island and South Africa
  • October 30: Bahrain and Kuwait
  • October 31: Albania, Bosnia, Croatia, Estonia, Greece, Guam, Hungary, Iceland, Kosovo, Latvia, Lithuania, Macau, Macedonia, Mexico, Moldova, Montenegro, Serbia, South Korea, Romania, Slovakia, Slovenia, Ukraine, and Thailand
Morgan Stanley’s Apple analyst, Katy Huberty, surveyed smartphone buyers in China recently and found a huge jump in purchase intentions for Apple’s iPhones in China, going from 24% a year ago to 50% today. At the same time, Samsung purchase intentions dropped from 30% to 13%, indicating a likely win for Apple in China.

Given the size of the Chinese and Indian markets, and considering the ultra-strong demand for iPhone 6 in China (now said to exceed 20 million pre-orders, according to a report on China's Tencent), it appears Apple could in fact be setting the stage for a major market-share upset over Android.

BCN, a Japanese company that tracks consumer goods, found that 22 of the 25 top selling smartphones for the week of September 22 to 28 were iPhones. So even in Japan (where Apple has seen a drop in market share), it appears Android faces tough competition, with Apple likely gaining back some of the market share it lost in the past year.

Let us also not forget that the race isn't just about market penetration numbers. It's also about profitability. Apple has a lonstanding tradition of kicking the market's ass in profitability. Four years ago, Apple had 7% of the computer market but 35% of the industry's profits. Something like this will happen in smartphones as well. Apple could well end up with 30% of the market but 50% of the profits. That will matter hugely to company performance and investor happiness.

As I write this (10:45 Eastern US, 16 Oct 2014), AAPL stock is $96.02. This is a bargain price, IMHO. I would be a strong buyer at this level.