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Merry Christmas from Webb of Science

24 Dec
Christmas lights in Dyker Heights, Brooklyn

seasonal glow

Chemistry Nobel, women, and the “choice”

7 Oct
A chocolate Nobel Prize

A chocolate Nobel Prize

On Monday, I mentioned that it was a good week for women in science. Well, it got even better today with the announcement of the chemistry prize.  Ada Yonath of the Weizmann Institute of Science becomes the fourth woman to be awarded a Nobel Prize in Chemistry (sharing the prize with Venkatraman Ramakrishnan of the MRC Laboratory of Molecular Biology  and Thomas Steitz of Yale University).

The science is essential for life, understanding the structure and workings of ribosomes. These packets within living cells that take the master plans encoded within geness and manufacture the working parts, proteins.

For an upcoming story, I’ve been thinking a lot about research careers, work-life balance, and the “choice” that’s often drawn in the sand, particularly for women, between work and family. Some of that comes out in Yonath’s interview on the Nobel website:

[AS] Yes. And perhaps particularly special to be a woman who receives it?

[AY] I’m sorry that I can’t, I can’t think this is because of my gender. And, I don’t think that I did something that is specially for women, or the opposite. During my time I had some very difficult years and I had very pronounced competition, all by men. But I don’t think that this is because I was a woman. I’m pretty sure that if I was a man too they would compete, if the men would get to where I was at that time. I think that it doesn’t help to be a woman in science. Maybe now, but not when I was progressing. But I don’t think that it disturbs, in my opinion. I may be wrong. I may be wrong: women try to explain me all types of things. And I think that women can make … women need, actually, they’re fortunate because if they don’t want to do science they can say, “I want to be with my kids.” And this is understandable, whereas a man cannot do this. So if we look at it from the other point, but this means also stopping science.

The Nobel recognition is about Yonath’s science, not her gender. But I find this quote fascinating, and it skirts around the main issue. She’s of a different generation (born in 1939), and I see one point: motherhood was  considered a socially acceptable– maybe even socially sanctioned– reason for a female scientist to leave the laboratory. A man would probably get more backlash for making a choice to leave the laboratory to raise his children.

But that choice, by a scientist of either gender, comes with consequences. I doubt that many of today’s women  use motherhood as a smokescreen for a waning interest in research. They leave for many reasons: because they decide to apply their knowledge in new ways, because they don’t see enough opportunities, and maybe even because they want to make more money. Some of them discover that the research lifestyle isn’t compatible with the family life that they’d like to have, particularly in the early years of their children’s lives.

Working on this upcoming story already had me thinking about my own decision to leave the laboratory. My choice didn’t come down to a line in the sand between career and family. I was single throughout graduate school and defended my dissertation shortly before my 30th birthday. But those issues colored my decision. By the time I finished my Ph.D., I sensed a culture of inflexibility.  I realized that I didn’t want to feel locked into lab work, and I wanted to be able to pursue other creative interests, and, yes, eventually have a family. Did those desires make me a less capable scientist? Absolutely not, but conventional wisdom would say that I didn’t want it “bad enough.” If I had sensed more flexibility– an environment more compatible with my personal goals–  would I have considered staying in research? I don’t know.


Nobel Prize for telomeres: focusing on the ends of DNA

5 Oct

It’s Nobel Prize season again, and the science behind this particular award for Medicine feels like a familiar friend. I got my crash course in telomeres and telomerase from a group meeting talk that one of my lab colleagues gave almost exactly a decade ago.

The science recognized was done a quarter century ago. DNA sequences have protective caps called telomeres that are maintained by a riboenzyme, telomerase, but the implications for the scientific understanding of aging, cancer and stem cells remain active research areas. Telomeres get shorter as we age, and maintenance of telomeres in cancer cells may help them continue to survive and divide. Part of the understanding of stem cells and their capacity for regeneration (or to cause cancer) will come from a better understanding of their telomeres.

This Nobel Prize story has many of the plot points associated with great discoveries, particularly the discovery of the telomerase enzyme, by Carol Greider in Elizabeth Blackburn’s laboratory on Christmas Day 1984. But notably, this award goes to two women: Blackburn of UCSF and Greider of Johns Hopkins University (They share the award with Jack Szostak of Massachusetts General Hospital and Harvard Medical School).

Though I wish that there were enough female Nobelists to make a double double-X chromosome Prize in Medicine less notable, it’s definitely a good day for women in science.

Revisiting DNA origami

1 Sep

Creating a genetic program to crinkle DNA into the perfect shape can appear to be a scientific stunt. But DNA origami is more than a molecular magic trick. In this excerpt from a 2007 TED lecture, Paul Rothemund describes the science behind the work– how a chain– based on its sequence– becomes a two-dimensional shape.

But this work isn’t all fun and smiley-faces– as an article in today’s New York Times about tiny transistors points out:

I.B.M. is also exploring higher-risk ideas like “DNA origami,” a process developed by Paul W. K. Rothemund, a computer scientist at the California Institute of Technology.

The technique involves creating arbitrary two- and three-dimensional shapes by controlling the folding of a long single strand of viral DNA with multiple smaller “staple” strands. It is possible to form everything from nanometer-scale triangles and squares to more elaborate shapes like smiley faces and a rough map of North America. That could one day lead to an application in which such DNA shapes could be used to create a scaffolding just as wooden molds are now used to create concrete structures. The DNA shapes, for example, could be used to more precisely locate the gold nanoparticles that would then be used to grow nanowires. The DNA would be used only to align the circuits and would be destroyed by the high temperatures used by the chip-making processes.

The DNA transistor mold– what a cool nanoscale idea: build the shape, pour your circuit and destroy the mold when you’re done.

P.S.: my earlier origami post from May– in case you missed it.

Exploding Color

4 Jul
NYC fireworks July 4, 2008 by Barry Yanowitz via flickr

NYC fireworks July 4, 2008 by Barry Yanowitz via flickr

Yesterday, we plotted how best to see the NYC fireworks display tonight with the least amount of inconvenience. In other years, we’ve had friends with roof access and good proximity. And a few years ago, we lived in an apartment in New Jersey that sat on a hill facing Manhattan with a bay window vantage point of much of New York Harbor.

That view was my favorite feature of that apartment, which we paid for in sweat equity– a climb up narrow stairs to the third floor. Any time of the year, but particularly on summer evenings, we might hear pops and crackles and head to the window to see where the colored bursts might appear next. Though we usually had no idea of the reason, the sky exploded in color just for us.

As a chemist I know that the palette of those bursts is all about burning different metal ions to produce fountains of shimmering color. And there’s a downside: some of the chemicals– such as perchlorates– in traditional fireworks can cause health and environmental problems. While researchers are working on greener solutions, conventional pyrotechnics are still cheaper.

Even if it means fewer displays, I hope more fireworks shows will “go green”– and red and blue and purple. Even if fireworks occur less often, the “added color value” would be worth it.

When Manhattan streets and the sun align

26 May
Manhattanhenge from Queens, Photo by David Reeves via flickr

Manhattanhenge from Queens, Photo by David Reeves via flickr

It’s just about time for Manhattanhenge– that moment where the sun aligns with Manhattan’s street grid. The magic times this year are Saturday and Sunday– May 30 & 31 and again on July 11 & 12.

On a day with a clear sunset, the experience is breathtaking. In 2005, when I still lived at the NE corner of Central Park, I happened to be riding a bus to City College for a soccer game on a clear Manhattanhenge evening. I highly recommend the bus viewing method– though it’s not good for photographs– the memory of that pink orb hovering over the horizon between city structures as I rode uptown still gives me chills.

Stonehenge at the solstice sunrise by tarotastic via flickr

Stonehenge at the solstice sunrise by tarotastic via flickr

I’ve been to Stonehenge, but I’ve never seen the Solstice sunrise. But that transient mixture of the cosmic with a human-produced structure, particularly when you transfer that experience to such a densely-packed urban location provides a collective opportunity to reflect on our individual place in relationship to the rest of the cosmos. Who are we and where do we fit? In our personal lives, our work, society, the cosmos? Twice a year, the streets we travel realign.

This year, now that Mayor Bloomberg has closed parts of Broadway near Times Square and Herald Square, I wonder if Midtown might not be the spot to view it. That is, if the hustle and bustle of tourists and synthetic light shows can pause long enough for a quiet, natural spectacle.

Summer is (almost) here

25 May
Memorial Day weekend in NY Harbor

Memorial Day weekend in NY Harbor

Fleeting moments between spring and summer are magic in my little corner of NY harbor. Bikes and rollerblades speed by– walkers, joggers, and marathoners-in-training drink in the cool breeze laced with sweetness (honeysuckle?). And the hardy fishermen (with an occasional woman) cluster in cultural pockets, speaking Chinese, Spanish, or Brooklyn-drenched English.

big fish

big fish

At another fisherman’s pocket, we found this catch-of-the-day, still gasping for breath. The anglers didn’t understand enough English to identify it to another passerby (probably 3 feet long– a striped bass– one of those fish that you actually can eat from NY harbor, my husband noted.).

By dusk we’d moved back inland stopping for dinner in our local diner, barely making a dent in the mounds of pot roast and the Greek combo.

Long walk + leftovers = holiday weekend

New York State of Mind

20 May
Summer afternoon in 2004-- view from the Staten Island Ferry, the harbor tour on an intern's budget

Summer afternoon in 2004-- view from the Staten Island Ferry, the harbor tour on an intern's budget

Five years ago today, I arrived in Manhattan with two cats, dreams of a new career, and a little overwhelmed by my move from the college-town Midwest. At that point, that Sarah could have told you generally what she wanted her career to look like in 5 years. But the woman who miraculously found a parking space on her block to unload the Toyota, waiting for her new roommate to bring her apartment keys, couldn’t have imagined what my life would look like today.

My NYC move was far from unusual– I came for 6 months of internships. I’d spent little time in NYC before I uprooted my life to come here– one day as a tourist when I was in high school. But NYC somehow hit the balance that I’d never found in my bounces between college towns and mid-size cities in the United States and Europe. Urban exhaustion initially hit me much like language exhaustion did when I lived in Germany, but I was somehow “home”– finally living in a space that combined the best of the eclectic United States and the history and culture of Europe. Earlier I’d always felt that my personality was somehow divided into geographic– or even continental– zones.

So, first I fell in love with New York, and chose to stay on and cobble together freelance work “temporarily” until I found “a real job.” Soon after the decision to stay, I fell in love a second time, with the man I later married. And as my career evolved, I realized that freelancing was, in fact, my real job after all.

Moving to NYC was a risk well worth taking, and what I didn’t realize at the time was how well my graduate school years, though tough and tubulent, prepared me for what has become my freelance science writing career. So, though I don’t know if Sarah from 5 years ago would recognize me, I definitely didn’t jettison everything she learned in the laboratory–  more about life than chemistry.

  1. Self-motivation— I learned how to independently manage a research project, plan experiments and budget my time. My current work is different, but the principles behind it are the same.
  2. Research— I spent a lot of time looking for written information and finding people who could help me with my research problems– not all that different from finding, talking to, and evaluating sources.
  3. Turning failure into a learning experience— Most scientific experiments fail on some level, but the learning comes from figuring out what went wrong. So near misses breed success. Failure also served as a catalyst for my writing career. The first time I applied for a writing internship in 2003, I was turned down– and completely devastated. If I hadn’t been sure that I wanted to do this, I might have given up then. I stiffened my resolve, got more clips, and moved on (and applied the next year). Resistance, failure, whatever you want to call it, serves as a gut-check. Does it mean that you need to make a turn and head in another direction? Or does it mean that you need to climb over or through the obstacle in your path?
Wandering through The Gates in Central Park in early 2005

Wandering through The Gates in Central Park in early 2005

So, here’s to five years– as a science writer and in NYC.  I’m excited to see what the next five bring.

Molecule of the Week: RNA

16 May
messenger RNA credit: Wikimedia Commons

messenger RNA credit: Wikimedia Commons

You have it, I have it. Many viruses are based on it. It’s RNA, which stands for ribonucleic acid. It’s DNA’s chemical cousin with just a few slight differences.

While DNA serves as life’s genetic blueprint. RNA is more of a multitasker. DNA stores information in a kind of vault, and the cell makes RNA-based copies that ferry that information to other parts of the cell to provide the program for making proteins, the true cellular workhorses.  RNA’s reactivity also makes it a little like proteins– it’s been shown to actually do chemical reactions.

So, why does RNA make the cut this week? Researchers have found a new way to put RNA together, which may help scientists figure out how life begins. (See the New York Times story here).

Because RNA has many talents, some scientists had proposed an RNA world, the idea that all life was originally based on RNA, that DNA and proteins developed later. But there was a problem. The segments that make up RNA (and DNA) are made from three building blocks. Researchers couldn’t figure out how two of those building blocks could have fit together on their own– there was no way for the reaction to happen without external help.

However, scientists have now realized that maybe they were trying to put the wrong pieces together. Instead of fitting together the three components (a ribose sugar, a base, and a phosphate group), they’ve found a new way to assemble the molecule, by breaking it up into different starting pieces.



Think of it like building with Legos. You build each piece on brick by brick. But in this case, two of the pieces just won’t fit together. Instead scientists broke the Lego pieces into smaller parts and found a way to make them all come together to make the right molecule.

It’s a great example of scientists taking a step back and thinking about an old problem in a new way.

Mammals to an extreme

13 May

I’ve been making the rounds of interesting New York City science events this week. Yesterday morning– along with a bunch of other journalists– I got a preview of the American Museum of Natural History‘s Extreme Mammals exhibition, which opens on Saturday, May 16.

Indricotherium © AMNH/D. Finnin

Indricotherium © AMNH/D. Finnin

Walking through the exhibit, it’s interesting to think about what we consider “normal” about mammals and how some of these examples, mostly fossils and model reconstructions, challenge that notion. The exhibit entrance is striking, a model of an ancient rhinoceros relative (Indricotherium), the largest-ever land mammal– so big that he’s the entry gate to the exhibit.

Batodonoides © AMNH/D. Finnin

Batodonoides © AMNH/D. Finnin

Next, of course, is the smallest– a model of a bumblebee bat– a little thumb size creature about the size of those little plastic animals that you sometimes see decorating the end of kids’ pencils or pens. Evolution may be random, but here it almost seems whimsical, like nature created a beautiful toy.

Sugar glider © AMNH/ R. Mickens

Sugar glider © AMNH/ R. Mickens

However, the cute centerpiece of the exhibits are live sugar gliders– little Australian marsupials that look a little like a cross between a squirrel and a bat– flaps of skin between their front and back legs serve as parachutes that allow them to glide.

It’s a fun exhibit with lots of interesting factoids about brain size, trunks, horns, and even scales– unexpected features on some unusual creatures. So, it’s worth a stop, and save time to watch the sugar gliders.