11/16/2005
LEDs in Motion
While I was on the cruise described in last week’s column, William Oliver Baker died at age 90. Bill Baker was legendary at Bell Labs, having served as its president and chairman of the board and as an advisor to five U.S. presidents. In 1952, when I interviewed for a job at Bell Labs, I found myself in a lab with Baker and Robert Burns, an eminent scientist. I hadn’t heard of either one of them. Burns asked me why I wanted to leave NACA, my employer at the time. I responded with some remark about being unhappy with my management there. I thought Baker was asleep; his eyes were closed. However, he opened his eyes and said, “Mr. Bortrum (he actually used my real name), if you came to Bell Labs and were placed in charge, how would you run this place?” I haven’t the foggiest idea what I replied but I got the job offer! Three years later, Baker was made vice president of research.
Baker was known for his curiosity and his broad knowledge about virtually everything. I like to think he would have found this week’s topic intriguing. Arriving at The Electrochemical Society (ECS) meeting in Los Angeles last month, one of the first people I encountered was a past president of the Society. Dick greeted me with the comment that he was using my “voluptuous” solubility curves in his classes at the University of Illinois. He was referring to the plots in a paper I published in 1960 in the late Bell System Technical Journal (not only is the Bell System long gone, but next week AT&T may be officially swallowed up by one of its offspring, SBC). My solid solubility curves for impurities in germanium and silicon were used worldwide because they were helpful in determining how to control the amounts of impurities in germanium or silicon transistors or other devices.
I never considered those curves to be “voluptuous”. However, the solubilities of most impurities increase with temperature and then decrease to zero at the melting points of germanium or silicon. This so-called “retrograde” solubility does give the curves a distinct resemblance to the profile of Dolly Parton’s upper torso viewed from the side. And it’s certainly true that “voluptuous” is ‘in” these days. One cannot escape it in the movies and on TV. Even on our cruise ship, with a largely older clientele, there were examples of extreme cleavage on the pool deck.
Coincidentally, on the plane to Los Angeles, I read an article titled “The Physics of Bras” by Anne Casselman in the November issue of Discover magazine. After publishing those “voluptuous” curves, I spent a decade at Bell Labs working on light emitting diodes (LEDs). My colleagues Ralph Logan and Harry White used gallium phosphide crystals grown in my lab to make the LEDs for the Bell System’s first working telephone with LEDs in the pushbuttons. Now, LEDs are everywhere in applications ranging from sneakers to stoplights in autos to Times Square billboard displays. In the 1960s, we might have anticipated many of today’s LED applications but certainly not the one discussed in Casselman’s article.
But first, let’s consider the breast and its construction. The article indicates that the engineering aspects of the breast are not fully understood. The breast is made up of lobes, 15 to 20 of them, and these lobes contain lobules ending in bulbs that produce milk. A network of ducts connects the bulbs and the bulbs and ducts are about the same size in all women, according to the article. The size of the breast is principally determined by the amount of fat and the presence of any implants. What seems to be up in the air is the question as to what it is that keeps the breast from sagging. Some experts believe that ligaments weaving among the ducts are responsible while others think the skin plays a major role.
Whatever the answer, for an increasing number of women, breast size is a problem. The increase in obesity has also led to an increase in voluptuosity (a new word?). Not only fast foods but also breast implants and hormones associated with birth control pills have raised the average bra size for American women from 34B to 36C. Almost a third of American women now wear D- cup or larger bras. I was shocked to read that a pair of D-cup breasts can weigh between 15 and 23 pounds! Casselman likens this to “carrying around two small turkeys”! No wonder over half of women who jog complain of breast pain.
How to address the problem for joggers or for that matter any well-endowed woman? For joggers, there’s the problem of one of Newton’s laws, that is force = mass x acceleration. In extreme cases, Casselman says that a falling large breast slapping against the chest can actually break the clavicle! More commonly, if the bra has thin straps, the pressure can be enough to cause furrows in the shoulders, pushing down on a nerve group running down the arm and causing pain in certain fingers. The function of the bra for the jogger is to support and limit the motion of the breasts. The article states that two women were the first to come up with the sports bra in 1977. They took apart two jockstraps, sewed them together and voila! - the Jogbra.
This compression of the breasts is one approach to limiting their movements during running or jogging. The other approach is the encapsulation bra, which consists of large molded cups to contain the breast. I gather neither of these approaches is really comfortable for the wearers of the bras. Enter Julie Steele, a biomechanist and Deirdre McGhee, a sports physiotherapist and graduate student in Steele’s team at the University of Wollongong in Australia. Steele’s group is studying the movement of the breast during jogging with the goal of designing a “smart” bra. If achieved, the smart bra would sense whether the wearer is walking, sitting or running and tighten or loosen appropriate parts of the bra accordingly.
Here’s where the LEDs come into play. The Aussie researchers are studying the three-dimensional movements of the breast in jogging women. They tag the subjects with LEDs on the breasts and sternum and record the motions of the breasts and the body for women jogging on treadmills without bras. Then, the joggers are fitted with specially designed bras containing LEDs, sensors to measure pressure on the shoulders and electrodes to measure muscle activity. The LED movements are fed into a computer system to analyze the breast movement. Even small breasts were found to move vertically up to 3 inches during jogging, while large breasts would sometimes jump out of the bra.
Apparently, the quest for a comfortable supportive bra is a very competitive area. I certainly didn’t know that Maidenform had an R&D department. Casselman quotes a Maidenform vice president as saying that making a bra is like building a bridge, with weight to be uplifted and supported. She says with large breasts that challenge grows “dramatically”. Apparently, the Australian researchers have made some progress but patent and competitive considerations preclude them revealing details now.
One of the more facetious arguments against intelligent design is the fact that men have breasts. I’m wondering if, with aging and the increasing weight problem, there aren’t some men who might have the same problem as large-breasted women. I’m reminded of a Seinfeld episode in which Kramer addressed this problem by proposing to market the “bro”, a bra for men! Could Kramer have been ahead of his time?
Allen F. Bortrum
|