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Mildred Dresselhaus, 1930-2017

By Shlomo Maital

dresselhaus

Mildred Dresselhaus

   On Feb. 20, MIT Professor of physics and electrical engineering, Mildred Dresselhaus, passed away at her home in Cambridge, MA. She was 86. Born Mildred Spiewak, she was the very first female Institute Professor at MIT (an Institute Professor is a super-distinguished professor).

   Dresselhaus was known as the Queen of Carbon, in scientific circles. She used magnetic fields and lasers to map out the electric structure of carbon and found that by stitching in alkali materials, carbon can become a superconductor. She pioneered in researching “buckyballs” (fullerenes), soccer-ball shaped cages of carbon atoms, widely used for drug delivery, lubricants and catalysts. She also had the idea of rolling a single layer of carbon atoms into a hollow tube, the nanotube, making a structure with the strength of steel but just 1/10,000th the width of a human hair.

     Dresselhaus published over 1,700 scientific papers.   Her life was one of struggle and perseverance. She was the daughter of poor Jewish immigrants from Poland, and grew up in the Bronx.   She went through university on scholarship.  

     She once recounted, according to the New York Times, “my early years were spent in a dangerous multiracial low-income neighborhood. My early elementary school memories up through ninth grade are of teachers struggling to maintain class discipline with occasional coverage of academics”.   From age 6, she travelled long distances on the subway. She got in to Hunter High School, in Manhattan, and then Hunter College. Her lifelong mentor was Nobel Laureate Rosalyn Yalow, from whom she took an elementary physics course.

     Why did she choose to study carbon? Because it was unpopular and considered uninteresting, she observed. She and her husband were hired by MIT in 1960, because MIT was one of the few places that would hire a husband and wife team. At Lincoln Labs, she was one of only two women, out of a scientific staff of 1,000.

         She is survived by her husband Gene, and four children, Marianne, Carl, Paul and Eliot, and five grandchildren.   She will be remembered as the first woman to secure a full professorship at MIT, in 1968, and she worked “very vigorously to ensure she would not be the last”, observed Natalie Angier, in the New York Times.

How Life Began on Earth

By Shlomo Maital

urey1urey2

Miller and Urey                         …. And their famous experiment

 

   Stephen Hawking’s brilliant PBS series Genius has a segment on how life began and evolved. In it the amazing 1952 chemistry experiment of Stanley Miller and Harold Urey (U. of Chicago) was described. The experiment shed light on how life began on earth.

     The experiment was beautifully simple. We know now that life is mainly made of proteins, and proteins are made up of amino acids.   But how did amino acids form? And what do amino acids do for us?

  • In the brain, glutamate is the main neurotransmitter (sending signals from one neuron to another, known as thinking) as neurotransmitters;   hydroxyproline is an important component of our connective tissue; glycine is crucial for red blood cells (that carry oxygen to all parts of the body); and another amino acid carries fat cells (lipids).

       Miller and Urey took methane gas, ammonia, and hydrogen gas, the gases prevalent in the earth’s atmosphere billions of years ago; they boiled water to create ‘clouds’ in the atmosphere; and added sparks, representing the lightning then occurring. Basically a very simple simulation of the gases in the earth’s atmosphere as it was when early life first formed, with some electrical energy from lightning.

       They ran the experiment for a week, then opened the flask and checked to see what happened.

         They found that three amino acids were formed. Amino acids are made of carbon, hydrogen, oxygen and nitrogen. The experiment showed how amino acids could have formed in the earth’s atmosphere…and, presumably, life began later, as the amino acids combined and became complex.

           For those who love the Bible, does this demean our faith? Not in the least. I asked a very religious relative about this, and his response was that evolution, and the Urey experiment, confirm the Biblical creation account, rather than deny it.   The beauty and complexity of all the forms of life that evolved from a handful of amino acids are surely inspiringly divine in their nature.

     As a postscript:     After Miller’s death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different amino acids produced in Miller’s original experiments.  

Blog entries written by Prof. Shlomo Maital

Shlomo Maital
March 2017
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