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02/01/2013
Toads, MRSA and Grounded Airliners
CHAPTER 30 - Toads and Batteries
When in graduate school at the University of Pittsburgh in the years 1946 -1950, I looked forward to going down the street to Forbes Field when the St. Louis Cardinals were in town. It gave me a chance to watch one of the truly great players in baseball history, Stan Musial. Even in the far reaches of the left field bleachers, where I usually sat, I had no problem distinguishing Stan, with his unique coiled up batting stance. Musial died last month and our paper, The Star-Ledger, had a long article about this scandal-free Hall-of-Famer. Musial's 3,630 hits have been exceeded by only Ty Cobb, Pete Rose and Hank Aaron in all of baseball history. The thing that impressed me most in the Star-Ledger article was Musial's consistency; exactly half of those 3,630 hits, 1,815, were at home while the other 1,815 hits were on the road! I saw a fair number of the latter while at Pitt.
Musial's death took me back to my chemistry roots at Pitt. Readers of these columns will know that I'm intrigued by roots of all kinds and I've mentioned sending National Geographic a swab sample from my cheek so they could check my DNA in their Genographic project. They traced my ancestry back to Africa and the ensuing migration path into Europe. This January's 125th Anniversary issue of National Geographic deals with exploration and the question of why we humans explore. One of the articles, "Restless Genes", by David Dobbs looks into the question as to whether there might be a gene that is responsible for exploration or at least for risk-taking in us humans. One candidate gene, which helps control dopamine, is in about 20 percent of us. However, there are studies that argue both for and against this gene being responsible for our exploring tendencies. Some think that a combination of our brain and our "clever" hands have led us to strike out into unknown territory.
I was intrigued by an example in the article of how a gene riding a migratory wave can become more common. The case cited was of migratory cane toads in Australia. Say you have a big bunch of these toads and they start spreading out into new territories. It turns out that, in the forefront of this migratory wave, toads have about 10 percent longer legs than the toads left behind. In that leading edge of the population, long-legged toads mate with other restless long legged toads. So, over time, the genes associated with long legs become the dominant genes in the exploring population.
I was intrigued by the cane toad and found an article in Wikipedia on the critter and its presence in Australia. I was surprised to find how big some cane toads are - some weigh in at 4 pounds and measure up to about 9 inches in length. The cane toad is one of those examples of an ecological experiment gone horribly wrong. They were introduced from Hawaii back in 1935 in an attempt to control the cane beetle, a native Australian bug that eats the leaves of sugar cane ,while its larvae eat the roots. Well, the toads really took off and those long-legged guys have now spread out as far as Western Australia from their points of introduction in northeastern Australia. Their population is now estimated at some 200 million!
I learned something about my own anatomy from the toad articles. The cane toad's parotid gland secretes a milky secretion that's toxic to many animals. It's apparently painful, but not usually fatal to humans. I was surprised on further research to find that I also have a pair of parotid glands, which are salivary glands. I now realize that as a child I suffered from parotitis, an inflammation of the parotid gland and in my case of mumps, sizeable swelling of the gland. Back to the toad, the venom secreted by its parotid gland can kill species that don't know any better than to eat one. The introduction of the toads has apparently caused a decline in some species that haven't learned to avoid eating the toads, reptiles being particularly threatened. Some birds have found they can eat the toads by going after their bellies, avoiding the parotid glands. I've often commented about the intelligence of various birds, the word bird-brained being quite inappropriate as a derogatory term.
Let's see, how did I get into this diversion about toads? Oh, we were discussing genes and how the genes for long legs would propagate in the advancing migration of the toads. I found another gene-related story that may be more important for us humans who enter hospitals for various purposes. In the November 23, 2012 issue of Science there's an article by Kai Kupferschmidt about a genome study helping to contain a MRSA (Methicillin-resistant Staphylococcus aureus) outbreak in a special care baby unit in Cambridge's Rosie Hospital in the UK. When three babies came down with MRSA, bacterial geneticist Julian Parkhill decided to do full-genome sequencing on the MRSA microbes from the three babies, as well as on microbes from 13 earlier cases that occurred in the preceding 6 months.
Parkhill's studies showed that the 3 recent cases and 8 of the earlier cases were of the same strain, while 5 cases were not. After a major effort to sterilize the whole hospital ward, there were no cases of MRSA for over two months. Then, another case appeared and it was of the same strain. Suspecting that someone was a carrier, 154 workers were screened and, sure enough, one worker who showed no symptoms was found to carry the strain that caused the outbreaks. When he was treated with antibiotics and the MRSA strain disappeared no more cases were observed. The article pointed out the possibility that the worker contracted the MRSA bacteria from one of the babies but, under the circumstances, it seems likely that the fellow was a carrier.
Well, enough about genes. Having spent 17 years at Bell Labs working on lithium batteries, I feel compelled to comment on a problem that has garnered a lot of publicity in the media recently. I'm talking about the recent problems with lithium-ion batteries in Boeing 787 Dreamliner aircraft that have resulted in Dreamliners worldwide being grounded until the problems have been resolved. Specifically, batteries in two planes from Japanese airlines caught fire, one while parked at Logan International Airport in Boston. I've never been comfortable with Logan Airport after being on a plane that almost landed on top of another plane while we both were landing! Wisely, our plane aborted the landing inasmuch as the other plane was underneath us!
Back to the Dreamliners, wanting to know of the latest developments in the case, I turned to Google and was struck by one item with the headline quoting a "battery expert" as saying that he personally wouldn't fly in a Dreamliner. Wondering who the battery expert was, I found a video clip of a recent CBS evening news broadcast in which Sharyl Attkisson interviewed George Blomgren, who had worked for Eveready. I know George well, we both having attended many Electrochemical Society and International Meetings on Lithium Batteries. His wife and mine bonded during those meetings and I have great respect for Blomgren's battery savvy. I must say that I would not be comfortable flying in a plane with lithium-ion batteries unless I was sure that the batteries and the battery monitoring and control equipment were of the utmost quality. Overcharge a lithium-ion battery and the organic solvents decompose, initiating a possible fire and/or explosion.
I've noted on occasion that I walk in the mornings at our local mall. Recently, the restaurant where I have coffee moved to a new location in the mall and the old site now houses a car dealership. I've not seen a car dealership in a mall before but there they are, the impressive looking Tesla autos powered by, what else, lithium-ion batteries. Who is the prime backer of Tesla? Elon Musk, the same guy who is in charge of SpaceX, the company now delivering supplies to the International Space Station. I was quite surprised to find that Musk also has come out with very critical comments on the lithium-ion battery used in the Dreamliner. His main criticism involves the large size of the individual cells in the battery and his feeling that the design is not one that permits heat to be dissipated if one cell should heat up, as in a short circuit.
Musk says that the lithium-ion batteries in the Tesla consist of small cells in a design that he feels should be able to handle problems with an individual cell. Way back, when I first heard of the Tesla, I was amused by the fact that the inventor was apparently, as far as I could tell, taking lithium-ion batteries of the same size being used in some electronic gadgets and just hooking up a lot of them to make the battery. Could it be that Musk and his Tesla colleagues are still doing the same? If so, are they the smart ones? After seeing the amazing job Musk has accomplished at SpaceX, I certainly would not count him out!
I never thought I would be quoting Al Jazeera but I found a report this week on an Al Jazeera Web site saying that Japanese investigators have concluded there's not a problem with the battery design for the Dreamliner, saying "the manufacturing process did not cause problems inside the battery". Their investigation apparently is now being focused on the charging and monitoring equipment. Regarding Al Jazeera, I've recently seen Al Gore on a number of talk shows promoting his new book. However, most of the talk I've heard has been devoted to his sale of his Current TV channel to Al Jazeera.
Finally, a disclaimer. I never worked on lithium-ion batteries. They were announced by Sony after I retired from Bell Labs. The batteries I worked on used pure lithium metal as the anode. The lithium-ion battery uses graphite as the anode, with the lithium inserted in between the layers of the graphite structure. Ironically, I did witness the notebook entry of Bell Labs' Samar Basu on the graphite-lithium anode. Sony acknowledged Basu's patent in their initial announcement in a battery publication. Whatever, I certainly hope that a safe combination of a lithium-ion battery and associated charging/monitoring equipment emerges from the Dreamliner troubles.
Next column, hopefully, will be posted on or about March 1.
Allen F. Bortrum
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