Season 1- Season 3 

August 13, 2011

How to stare down the emperor (of all maladies)*

"Any important disease whose causality is murky, and for which treatment is ineffectual, tends to be awash in significance...The disease itself becomes a metaphor." Susan Sontag 

On Saturday, August 13, 2011, not long after the peak of the Perseids, David Stern gave a simple and elegant introduction to how normal cells lose some of their exquisitely fine tuned functions and go down the perilous path of cancer. Cancer is a complicated disease, defined in the OED as a "an uncontrolled proliferation of cells, typically with invasion and destruction of adjacent normal tissue."  Normal cells have robust machinery to cope with errors that might occur when a cell progresses through the multiple steps required for it to successfully replicate.  Indeed, with the constant onslaught of a variety of environmental insults as well as the choices we make in things as mundane as food and drink, and the lives we lead, the fact that there aren't more cases of cancer than the million cases that are reported each year in the US alone, is testament to the almost infallible repair machinery with which are cells our cells are equipped.  And it is this cellular repair machinery that also handles the majority of random errors that might occur, errors that could lead to mutations that could potentially lead to a cancer. It is important to note that majority of the million odd cases of cancer are not hereditary; hereditary cancers are estimated to be between 10-20% of all diagnosed cases.

Appreciating the genetic diversity of the human species, and the fact that cancers are a consequence of mutations in DNA, acquired mostly randomly and sometimes inherited, brings into greater clarity why it has been so difficult to "find a cure" for cancer. Unlike most other diseases, manifestation of cancer can vary tremendously between patients, even if the organ affected is identical.  On August 5 1937, the National Cancer Act established the National Cancer Institute to "to support promising research projects on the causes, prevention, diagnosis, and treatment of cancer; collecting, analyzing, and disseminating the results of cancer research conducted in the United States and elsewhere; and training and instruction in the diagnosis and treatment of cancer." Almost seventy-five years later, we have come a long way in diagnoses and treatments, but cancer will soon overtake heart disease as the leading cause of death in the US. This despite what Richard Nixon said in his State of the Union address in January 1971: "I will also ask for an appropriation of an extra $100 million to launch an intensive campaign to find a cure for cancer, and I will ask later for whatever additional funds can effectively be used. The time has come in America when the same kind of concentrated effort that split the atom and took man to the moon should be turned toward conquering this dread disease. Let us make a total national commitment to achieve this goal."

After introducing us to the basics of how cells replicate and the many ways this replication can go awry, David Stern took us through a brief history of how cancer therapies have      reached the point they are at today: from the traditional paradigm of surgery-chemotherapy-radiation, to examples of cancers like some breast cancers having benefited from research that has developed targeted therapies like Herceptin.  With this as a backdrop, he gave us a glimpse into what lies ahead for cancer treatments and cures, in the context of the uniqueness of each tumor.  Much of this is propelled by the enormous advances in technology that have now permitted sequencing  DNA from patient's genomes, allowing identification of mutations in the tumor DNA . This information then has the potential to allow for the design of specific therapies, which would hopefully also have fewer side effects that are typical of traditional therapies. 

“A good designer must rely on experience, on precise, logical thinking; and on pedantic exactness. No magic will do.” - Niklaus Wirth 

Thank you, David, for a window into the challenges and complexities underlying designing better treatments and cures for cancers.

*Apologies to Siddhartha Mukherjee. This cafe was an exercise in learning about the ways in which we could stare down this Emperor of All Maladies that Siddhartha Mukherjee has so eloquently written of.

May 16, 2011

If not for Henrietta Leavitt..

 ...we would not have "The Realm of the Nebulae", the 1935 Silliman lectures presented by Edwin Hubble at Yale University.  And were it not for those lectures where Hubble described his observations on the expansion of the universe, relying largely on Henrietta Leavitt's earlier findings, we would likely not have a telescope named Hubble.

Over the course of the most recent Tilde Café afternoon, Moshe Gai regaled attendees with the contributions of a number of scientists who have enabled us to gain fascinating insights into what comprises the cosmos. His narrative was extensive and absorbing, and abbreviating here will not do it justice.  Worth noting here though, is that those who had participated in previous cafe discussions on dark matter and dark energy got an excellent historic perspective of the fields.  The footage from the afternoon will be available by late May 16, 2011 at http://www.youtube.com/tildecafe. 

"Ms. Leavitt did view many plates

And studied the images’ traits;

She found a Cepheid variable

Later used by Edwin Hubble,

And now we get telescope updates."

Thank you Moshe, for an enjoyable afternoon.

April 16, 2011

Tripping up neurons at the recent Tilde Cafe discussion

Turns out that morphine, mint and chili peppers do share some things in common.  As Mortimer Snerd would have said, “Who’d have thunk?!”  Dr. Daniel Broom gave Tilde Café attendees who’d braved gusts of 40 mph winds and rain, a primer on how neurons respond to painful stimuli, and how this neuronal response is transmitted to the brain via electrical signals that travel at up to 22-23 mph.  To put this in some perspective, if a person 5 feet tall stubbed her toe, her brain would receive that information and she would respond, perhaps with a scream, in about a tenth of a second.  Which is just as well, because if it were a graver stimulus that her toe received, she would definitely need to respond very fast.  And this is where the role and perception of pain becomes important.  

 “A neuron who sensed some strain

Said "This is really a pain",

It said to its friend,

"This must really end",

So a message was sent to the brain.”

 -Anonymous

As became evident through what Dan shared with us, the ability to perceive pain is essentially an aspect of survival.  We were also introduced to two conditions of abnormal pain perception viz. hyperalgesia and allodynia, both of which are not entirely uncommon. Using response to temperature as an example of a pain pathway, we learnt that there is a family of proteins that are gatekeepers or channel guards located at one end of a neuron, and respond to temperature. These proteins are called ion channels and their main job is to maintain the correct balance of specific ions, i.e., chemical entities that carry a positive or negative charge, inside the neuron; an imbalance of ions results in the generation of an electrical charge which gets transmitted through the length of the neuron. Interestingly, there are defined ranges of temperature assigned to each family member; for example, TRPV1 (read as Trip Vee one) is an ion channel that responds to temperatures greater than 43 Celsius or 109 F – the temperature of a fairly hot shower. When exposed to the appropriate temperature, the ion channels physically reorient themselves permitting ions to pass through, resulting in an ionic imbalance which translates into a rapid electrical signal being transmitted to the brain, The Decider of what action to take!  

Neurons have specialized proteins that respond to specific stimuli. It quickly became clear that electrical conductance through the neurons to the brain is one of the key mechanisms underlying our ability to sense pain. The electrical signal is conveyed by the “first responder” neuron to specific areas in the spinal cord, from where another neuron picks up the electrical information and conveys it to the brain.  From there, a series of hand-offs of information occur, leading to one being actually cognizant of a noxious agent.  In general then, the gatekeeper proteins and their neighbours, are very important in pain perception and ensuing responses.  Morphine’s binding to specific proteins (opioid receptors; often located not very far from ion channels) on neurons allow pain perception to be blunted.  Similarly, menthol from mint, and capsacin from chili peppers also bind to specific proteins on neurons, affecting the ability of the proteins to act as effective gate-keepers, resulting in altered concentrations of charged chemical entities in the neuron, and generation of an electrical impulse that is conveyed to the brain for appropriate action by you!  

This synopsis does no justice at all to the content of the afternoon which you can access at http://www.youtube.com/user/tildecafe in the next day or so.  Thank you, Dan, for a very illuminating afternoon – and for the samples of Wasabi peas and Mentos too – for those did not attend, they were excellent examples of perceived temperature changes by way of other stimuli!  He did bring along some chili peppers too, but we took his word on the effect of capsacin, the substance that renders a pepper hot. Incidentally, the hottest chili pepper according to the Guinness Book of World Records is the Naga Viper Chili as of Feb.2011.

March 5, 2011

You can't take 3 from 2; 2 is less than 3* - an afternoon spent with Amanda Folsom

"I'll tell you once, 

and I'll tell you again. 

There's always a prime 

between n and 2n." 

— Paul Erdos

Professor Amanda Folsom drew Tilde Café attendees, only a few of whom had a robust background, into her world of pure mathematics.  And what a fascinating world that is!  True to her original assurance that she would not engage us in mathematical operations beyond simple addition and subtraction (and a touch of multiplication) that is taught in elementary school, she introduced us to concepts that few were familiar with.  And then proceeded to astonish us with how beguiling simple, yet inherently complicated/complex is the puzzle that has engaged mathematicians for almost a century. After showing us a short series of (small) numbers, she asked us to predict the next number and thus figure out a pattern; while all our answers held for at best the next number, it quickly became clear that the series was more complicated!  She then told us that the series we were looking at was that of partitions of numbers going sequentially from 1 to 8, and then using a $5 bill explained the concept of partitioning of numbers - how many ways can you arrive at the number 5 - seven ways.  The number of partitions of a number goes up dramatically, from 42 partitions for 10, to 190,569,292 partitions for the number 100!  Around 1918, Srinivas Ramanujan presented mathematicians with a formula to calculate the number of partitions an integer can have; however, he appended a cryptic comment that has been finally decoded by Professor Folsom and her colleagues. Their finding sheds a new light on how to look at partitioning. The February 2011 issue of Scientific American has an excellent article (http://www.scientificamerican.com/article.cfm?id=mathematics-ramanujan) about their findings which were presented at a specially convened symposium at Emory University on January 21, 2011. Tilde Café attendees were privileged to hear of these very new results directly from an author of research that presents a heretofore unappreciated fractal view of partitions. For those who are keen on reading the original paper, it is posted on the American Institute of Mathematics website (http://www.aimath.org/news/partition/folsom-kent-ono.pdf).  And the fact that Professor Folsom is at Yale is indeed a happy convergence of events, since the term “fractal” was coined by the late Benoit Mandelbrot who was in the Department of Mathematics at Yale.  He coined the term when he was at IBM’s Thomas J. Watson Research Center. 

I think everyone who attended Amanda’s café will look at numbers very differently henceforth – the patterns she described, including those that follow Benford’s Law! Check out a wonderful audio link on the applications of the pattern described by this law - http://www.radiolab.org/2009/nov/30/from-benford-to-erdos/. Thank you Amanda, for nudging our mathematical curiosity, and for helping us get a better appreciation of what keeps a pure mathematician excited. The excitement is indeed infectious as evidenced by the response from those present.

The footage of this café will be posted in the next couple of days. 

 *Apologies to Tom Lehrer, and BBC's TW3 - taken from his song "New Math".

January 23, 2011

Rosie, R2-D2, C3-P0 and 3Ds

“We are survival machines -- robot vehicles blindly programmed to preserve the selfish molecules known as genes.” -RICHARD DAWKINS, The Selfish Gene

The common thread in the title here is robots/robotics: Rosie (from the Jetsons), R2-D2 and C3-P0 (from Star Wars); however, 3Ds is really not a robot but the three “D”s that drive the field of robotics to some extent. If a task is Dangerous, Dirty or Dull, designing a robot may well be considered for it.  When Professor Aaron Dollar began his conversation with a large number of Tilde Café attendees, he asked, "if you had a robot, what would you like it to do?"  Interestingly, most of the responses fit into either the Dull, Dirty or Dangerous categories.  It was clear that our general understanding of robots and robotics is guided by the three Ds.  However, the potential of the field extends well beyond these three Ds.  And this is where Aaron Dollar’s research becomes really important.  One of his focuses is designing a prosthetic hand that has a soft-touch – a prosthetic hand that comes close to that of a human hand, and can handle tasks as diverse as picking up a delicate egg, to handling a rigid object.

Designing a hand that recapitulates a human hand requires taking into account multiple factors, such as the number of joints (more than 30), the extensive network of nerves and muscles that are profoundly efficient, ability to make accurate decisions based on object to be manipulated, and the weight and cost of the prostheses.  An exquisite integration of all these factors, to yield the desired prosthetic hand requires a knowledge of areas as diverse as material science, biomechanics and psychology. Indeed, by the end of the afternoon we had a greater appreciation of the amazing teamwork that is required in designing an efficient robot, and although robotics has made inroads in routine jobs like assembling cars, its application to refining prosthetics is still a young field.

If you visit the GRAB lab website - http://www.eng.yale.edu/grablab/ you will find links that tell you more about Aaron Dollar’s research.

Many thanks to Aaron Dollar for an enthralling afternoon, and to NOVA/PBS for their support of it. 

Please visit http://www.crisp.yale.edu/index.php/Education_Outreach#Connecticut_Making_Stuff_Outreach_Coalition for additional events planned through the CT Making Stuff Outreach Coalition.  

December 19, 2010

Of ratios, majors, minors, intervals and perception - a harmonious convergence of math, music and mind

The James Blackstone Library auditorium was reverberating with the sound of the monochord that Professor Ian Quinn had brought along to demonstrate some of the points he made during his discussion on Math, Music and Mind.  Upon asking how many people in attendance had heard of Pythagoras and the context in which we had heard of him, Ian told us about the central place that Pythagoras appears to have played not only in mathematics, but also in early western music.  Using his mathematical acuity, it appears that Pythagoras was able to transform music into mathematical equations.  This led to a realization that distinct mathematical ratios define consonant and dissonant musical groupings (major-minor configurations etc).  Interestingly, there were concomitant, independent and similar math-music correlations developing in India and China. However, a comparison of the principles underlying the contemporary versions of these three forms of music reveals distinct mathematical ratios, appreciation of whose aesthetic is profoundly impacted by acculturation.  Thus, although one can use mathematics to define musical intervals, the brain "embraces" those intervals it has been most exposed to.  Using a few bars of music recorded at different times between 1927 and 1999 in Alabama, Ian also demonstrated how over the passage of time, less than a century, nuances in music have been lost - in the 1927 recording, the tuning for the song was more fluid with musical ratios that appear less acceptable in contemporary western music; and this fluidity has been eroded resulting

in a more uniform and homogeneous product.  

Professor Quinn left everyone looking forward to another discussion on the topic, as music impacts almost every region of the brain - we barely scratched the surface on Saturday!  For those who would like to hear a panel discussion on music and the brain [Notes and Neurons], do check this link from the 2009 World Science Festival - http://www.worldsciencefestival.com/video/notes-neurons-full.  I would also like to point you to an excellent online magazine on mathematics, that has a collection of articles on music - http://plus.maths.org/content/taxonomy/term/251

Thank you Ian, for a really engrossing afternoon!  

"Music is the pleasure the human mind experiences from counting without being aware that it is counting." - Leibniz

November 14, 2010

"If black boxes survive air crashes — why don't they make the whole plane out of that stuff?"

— George Carlin

Now that was one question we did not ask Professor Sharvan Kumar at the recent café discussion!  Once again, in keeping with what seems to be a fairly well established pattern, after a dreadful week weather-wise starting with snow on Monday, Saturday was a clear crisp autumn day.  And following said pattern, we had a hard-core group of aircraft aficionados and inquiring minds in attendance, with other well intentioned folks falling prey to the lovely weather.  Jackie Garofano, the Education and Outreach Coordinator of the CRISP program that is spearheading the CT Making Stuff Coalition mentioned in my previous e-mail, talked about other programs being organized by the coalition.  She also brought along some informational material about the soon to be broadcast PBS special.  Those who missed this wonderful afternoon can catch it on the café website later this week. 

Many Tilde Café discussions also have had an uncanny connection to things in the news – a report on the largest marine virus – the  Cafeteria roenbergensisvirus was published two days after Dan DiMaio telling us about the world of viruses; a week after Paula Kavathas told us about communal harmony between humans and microbes, a paper was published on how diet can influence the genetic diversity and functionality of the human gut microbiome; close on the heels of Caroline Zeiss telling us about the platypus, the NY Times had an excellent article about the brainy Echidna.  This time it was the Airbus A380 and the Boeing 787 stories that were pertinent to Sharvan Kumar’s café discussion. 

With a quick background on the inside of a jet engine and the demands placed on it, Professor Kumar made clear the limits and limitations that impact refining jet engine parts.  An enormous amount of research goes into designing parts that are resilient to extreme conditions, particularly higher temperatures (more than 2000 Celsius), and materials science is the foundation of this research.  Higher speed engines run at higher temperatures and it has taken 35 years to design, create and refine functional parts that can withstand almost 100 Celsius higher temperatures than was possible in the 1960s.  The materials used are carefully calculated combinations of naturally occurring elements and these are subjected to rigorous testing before they can be employed in passenger aircraft.  Thanks to learning a little about aircraft engines and their design, we all left the afternoon with a much greater appreciation of what materials science is and the exciting opportunities and unrealized terrain that exists in this discipline of MAKING STUFF: Stronger, Smaller Cleaner, Smarter

I simply can’t send this e-mail out without:

A Caution to Everybody

Consider the auk; 

Becoming extinct because he forgot how to fly, and could only walk. 

Consider man, who may well become extinct 

Because he forgot how to walk and learned how to fly before he thinked. 

-Ogden Nash

Much thinking goes on in the design of jet engines, as we learnt from Professor Kumar, so our flight into the future is in good hands!  Thank you so much to all who attended.

And I quote here from an e-mail sent by Professor Kumar: “I was especially impressed by the audience who showed so much interest and stayed with me during the whole presentation and made the experience really memorable for me. If in any way possible (for example with an e-posting of speaker feedback), please extend my sincere thanks to every member of the audience that showed up, participated and made the overall experience so rich.”

October 23, 2010

The uncanny connection between wonderful weather and Tilde Café discussions continues – Branford had excellent autumn weather on Mole Day, when Professor Daniel DiMaio captivated café attendees with matters viral – the disease causing ones, not the (pseudo)eponymous computer viruses.  After learning about Mole Day and the significance of a mole –the unit, not the animal, we were introduced to the world of viruses.  Virology, the study of viruses, has a long history and virologists have been well represented in the canon of Nobel laureates.  Following providing us with a basic distinction between disease causing entities – bacteria, viruses and other parasites, with Dan’s encouragement attendees came up with a list of commonly known viruses. From that list we learnt that while viruses are indeed forces to contend with, the rabies virus has been the only virus known to date to be 100% lethal; moreover, the only diseases that have been completely wiped out have been of viral origin – small pox and rinderpest.

One might think that on a certain level, while inert outside a host, some viruses like the influenza virus are “clever” enough to continually change so that they can escape vigilant immune systems.  But it is not a matter of smartness (indeed, viruses don’t think!).  Rather, it is a consequence of rapidity of replication which therefore comes with a lack of “quality control,” leading to random changes in the virus.  These changes enable the virus to dodge the immune system, and sometimes, even carefully designed vaccines.  We also touched upon the reasons behind why certain viral diseases which were earlier restricted to tropical climes (e.g., Dengue fever) are now finding their way to cooler regions: climate change as well as globalization (both topics discussed in previous cafes).  By the way, the etymology of the word vaccine lies in the first treatment of small pox patients – another fascinating story we heard on Saturday.  A keen attendee asked Dan towards the close of the afternoon, how he could sleep at night with all the things that still need to be done and understood to secure us from these continually changing and newly discovered viruses!  This resulted in the uplifting closing remarks that studying viruses is of great consequence, for a number of reasons, not the least of which is that we now know that at least 15% (and perhaps we will find more) of cancers are because of viruses; further there is tantalizing evidence implicating viruses in age related neurodegenerative diseases such as Alzheimer’s, and even in obesity – of course much more research is required to verify these, and then yet more to find ways to stymie the involved viruses!

Thank you very much Dan, for an excellent and stimulating conversation on viruses.

September 18, 2010

"Unless someone like you cares a whole awful lot,

nothing is going to get better, it's not."

-The Lorax, by Dr. Suess

The earth receives almost 1.7X105 TW of radiation from the sun per year.  Most recent estimates indicate that in one year the planet consumes 16TW of energy.  More energy hits the earth from the sun in one hour that the whole world uses all year!  Plants use energy from the sun to carry out photosynthesis, and really they, and other chlorophyll containing species use the sun extremely efficiently.  In fact were it not for their efficiency, we wouldn’t have fossil fuels, and if we didn’t have fossil fuels, we wouldn’t have had the recent disastrous spills.  However, inefficient photosynthesis would mean lower levels of oxygen, and that would mean well, we wouldn’t really have been around in the first place to listen to Gary Brudvig talk about these and other important and fascinating issues that surround accessing alternate (non-fossil) fuel sources!  In the process we also learnt of the solar-powered sea slug:"It's the ultimate form of solar power: eat a plant, become photosynthetic"  - an example that is similar to what Paula Kavathas talked about back in March 2010. Gary also told us about the recent success of his research group (still unpublished) in designing a solar bioinspired fuel cell.   Although the current output was low, the experiment lays the foundation for pursuing this possibility, which is fundamentally trying to follow what Nature has refined in plants. Gary pointed us to many resources, links to which are posted in the Download/link to material from past discussions section.

Many thanks, to all who attended, to Common Grounds for providing food and beverages, to the Blackstone Library, and above all to Gary Brudvig for an energetic Tilde Café discussion!  The footage from the afternoon will be posted by the end of the coming week - please checkhttp://www.tildecafe.org/Home/video-of-past-cafes for updates. 

“I have no doubt that we will be successful in harnessing the sun's energy... If sunbeams were weapons of war, we would have had solar energy centuries ago.” – Sir George Porter 

July 10, 2010

A key to the dynamics of truth and empathy - Oxytocin

While the names may sound similar, it was very clear from Professor Meenakshi Alreja’s very illuminating presentation today, that the physiological effects of Oxytocin are unique and not at all like those of OxyContin.  Besides, oxytocin, about which she informed us today, is a hormone made up of nine amino acids; OxyContin is a prescription opioid analgesic – very different, indeed!

After introducing us to the fascinating observations and studies (done on prairie voles and meadow voles) that showed the importance of oxytocin in engendering a greater tendency to huddle and groom, Professor Alreja talked about work from her laboratory as well as from others’ that has attempted to narrow the sub-regions of the brain that respond to oxytocin, and the ensuing behavioural changes.  Based on results from experiments on human subjects, those receiving nasal sprays of oxytocin exhibit much higher trust and empathy than do subjects receiving placebo sprays.  Interestingly, in other experiments it was shown that stress levels of children are reduced when the child is hugged by a parent, or even hears the comforting voice of a parent on the phone.  Thus, not only does oxytocin play an important role in childbirth and nursing recognised for well over 50 years, it also plays a critical role in navigating social interactions and in creating favourable and trusting situations.  Finally, the therapeutic potential of oxytocin is being evaluated for the treatment of social disorders characteristic of autistic patients.  You can read a summary of this latter work at - http://www.sciencedaily.com/releases/2010/02/100216221350.htm 

Thank you, Meenakshi, for providing a window into the workings of a fascinating hormone, the effects of which certainly play a critical role in guiding interactions which we don't often think of as important.  And of course for patiently answering the many questions we all had of you.

April 25, 2010

Space is big

Space is Dark

It's hard to find

A place to park.

-Sidney Harris (American Scientist magazine, 1975)

In a small way, Tilde Café celebrated Hubble’s 20th birthday yesterday at the Branford Library, with Professor Priyamvada Natarajan’s description of her research which uses images collected by the Hubble telescope.  For those who were unable to attend, I hope the video that I will post later in the week will do justice to the excitement that her discussion generated.  Many of us have seen images from the Hubble over the years (please checkhttp://hubble.galaxyzoo.org/ for links to images), but few of us understood what they meant (certainly I didn't!).  

 That is not to say that an hour of excellent explanations by Priya, of some of the phenomena responsible for the resulting Hubble images is enough to make us even amateur cosmologists, but it certainly has primed me to make efforts to learn more about it!  It also helped that we had heard a little about dark matter and energy and dwarf galaxies from previous discussion leaders Marla Geha and Daniel McKinsey.  Hopefully the younger attendees of the cafe will consider the possibilities of studying astronomy, cosmology and physics when they go to college!

Priya has generously offered to answer questions you may have after hearing her speak – she can be reached via her website -http://www.astro.yale.edu/priya/

 Please check the café website for the video of the afternoon, later in the week.   In the meantime, you could also view a related presentation by Patricia Burchat a particle physicist, recorded for TED in February 2008 - http://www.ted.com/talks/patricia_burchat_leads_a_search_for_dark_energy.html

The next café will be on July 10, 2010.  Enjoy the rest of spring, and see you all in summer.

April 11, 2010

175 years and thousands of tortoises later, hope springs thanks to DNA sequencing technology and superb sleuthing!

“A tortoise, tired of being slow,

Impatient to get up and go,

Took off his large and heavy shell

And left it lying where it fell.”

-Richard Buckley

Well, it was the whalers back in the 1800s and pirates too, we learned on Saturday, who were responsible for picking up tortoises from islands in the Galapagos archipelago and then randomly throwing them overboard when the ships got too crowded.  This is one explanation for how subspecies from one island may have “arrived” on other islands.  Tracing their lineages and which island these tortoises originated from, has been spearheaded in large part by the work of the Gisella Caccone (http://www.yale.edu/caccone/research_current-conservation-genetics.html) the most recent discussion leader at the Tilde Café series. Her research is conducted in conjunction with Jeffrey Powell, also at Yale University. In 1835, Charles Darwin and the crew of the Beagle spent five weeks in the Galapagos archipelago when he detailed the expansive diversity on islands that were merely 30-50 miles apart.  The Galapagos Islands, named because of the shape (saddle-back) of many of the tortoise carpaces, are home to several endangered species.  Lonesome George, is the last living Galapagos tortoise found on Pinta Island in 1971.  He was transported subsequently to the Charles Darwin Research Centre on Santa Cruz Island where he currently resides.  There has been no success in propagating his line, but thanks to the work of Gisella’s research group, after analyzing the DNA from 27 tortoises on Isabela Island, one individual with almost 50% of its DNA being characteristic of Pinta Island tortoises, has been identified.  Although it is not a “pure breed”, these efforts when extended to the +2000 population of tortoises on the island will hopefully (and likely) identify other tortoises, increasing the chances to repopulate Pinta Island with its native tortoises.  Incidentally, the robust genetic profile of the Pinta subspecies was compiled by analyzing a number of tortoise samples stored in museum collections.  Similar efforts are underway to repopulate Floreana Island with its original tortoise: currently the pure breed is extinct, but Gisella’s research has revealed Floreana descendants on Isabela Island.  Using tried and tested methods of selection practiced by dog breeders and other animal breeders, it is conceivable that in the next 50-60 years Floreana Island tortoises will be resurrected; it is, as she called it, her Lazarus Project! Through this most recent presentation and the one on genetic ancestry in November 2009, we have seen the harnessing of an extremely powerful technology to trace the lineages of humans and tortoises, revealing histories that are fascinating, while also enabling the possibility to repair lost legacies. 

Thank you Gisella for an illuminating afternoon.

March 20, 2010

You are what you eat!

Happy Spring!

Not long after the moment of arrival of Spring, we met at the James Blackstone Libaray in Branford to learn more about how each of us is actually a host for communities of microbes.  That's right, we have nearly 1000 species of microbes living with us quite harmoniously in our intestines!  Without them, we'd be in big trouble.  Professor Paula Kavathas told us about microbes that are beneficial and harmful to humans, and introduced us to the rudiments of how our immune system is capable of distinguishing the two.   According to some estimates, microbes in our body outnumber our own cells by almost a factor of 10.  Among the other things she told us, we learned of the importance of pre-biotics and pro-biotics in maintianing health, right from birth.  And yes, while "you are what you eat", what you eat also influences that community residing in your gut!  One piece of information she gave us certainly left a mark  - how our bodies retain the ink from tattoos...it's all in the immune system!  

Thank you so much Paula, for a really informative afternoon.

For possible origins of the phrase "you are what you eat" - please go to http://www.phrases.org.uk/meanings/you%20are%20what%20you%20eat.html for some interesting information.

February 28, 2010

In search of balance

Those who came for yesterday’s Tilde Café discussion were lucky twice over – the roads were not overrun with snow; plus they had an opportunity to listen to and speak with Dr. Pachauri, Chair of the world’s leading authority on climate change, the IPCC. The afternoon started with a brief and excellent introduction on remarks made by Arrhenius back in 1906 (http://en.wikipedia.org/wiki/Svante_Arrhenius) related to greenhouse gases and their contribution to warming, and led to a discussion on the role of not only scientists, but all citizens to shoulder the responsibility in addressing the issue of climate change. This can be achieved by implementing something as simple and feasible as initiating discussions on what can be done locally. Using technology to our advantage and educating ourselves about climate change is another route to create a more cohesive and organized effort to effect changes that will at a minimum slow the course of climate change. The caveat here of course is that some technology can actually drive us faster down the path we seem to be hurtling through, so it is important that we also make wise choices in using technology! I think it is safe to say that the first step to tackling the issue is a civil, rational and responsible dialog that will lead to greater awareness.

I hope that those who have attended previous discussions, for example the ones led by Gordon Geballe on industrial ecology, Tom Pollard on evolution, Caroline Zeiss on the platypus, and by Michael Donoghue on biodiversity, will see a continuing thread between those afternoons and the most recent discussion. If you missed those, please check out the videos posted on the café website. For those who could not make it to the most recent conversation, I will be posting the video of the afternoon by the end of the week. Also, in the “links” section of the café website, I will post links to the IPCC Synthesis Report mentioned by Dr. Pachauri. Thank you all for coming and engaging in a very important topic of discussion.

Thank you Dr. Pachauri for giving us an hour of your busy afternoon!

February 22, 2010

From bits to qubits on a sunny February afternoon

Old Punxsutawney Phil did indeed tell us on February 2, 2010 that there’d be six more weeks of winter but we had a respite on Saturday, with positively lovely spring weather.  However, the warm weather could not attract those who wanted to learn about quantum computing from Professor Steven Girvin.  It was an excellent choice to come to Nellie Green’s for a bit to listen in.  Without confounding us with equations, Steve really simplified the complexity of qubits and other related terms for those of us who are not physicists.

He even introduced us to a couple of sentences in Swedish!  We learnt that there is not just an “on” and an “off” state, but also something "in between" in quantum mechanics, and how this can be exploited in the design of a quantum computer.  Steve is a theoretical physicist who collaborates with his experimental colleagues and together they have “created the first rudimentary solid-state quantum processor, taking another step toward the ultimate dream of building a quantum computer.” – (outlined in the article here http://www.sciencedaily.com/releases/2009/06/090628171949.htm).  It was sobering to learn that the temperatures required to conduct these experiments are so low, they are only found only in the Boomerang Nebula.

For those who attended, I hope you’ve done the homework assignment Steve gave us – derive how you need 2.25 peeks to find the queen from four cards placed face down!  This was an exercise to illustrate how the laws of quantum mechanics allow you to find the queen in one try, whereas classical mechanics requires an average of 2.25 tries.

Thank you Steve for the generosity of your time, and for a wonderfully informative afternoon.

January 23, 2010

Standing room only - whilst we learnt that humans share much more with monkeys than many would care to acknowledge!

A huge thank you to Professor Laurie Santos who came out to Branford and told a packed house about one aspect of her extremely fascinating research. The turnout was much higher than anticipated and every inch of occupiable space in Cranberries was taken; unfortunately several people could simply not be accommodated. Apologies to those who belong to the latter category. However, please note that as for the other cafe discussions, this one too was recorded and I will try to have the footage posted next week.

After giving us a quick background and examples of decision making observed in humans - babies to adults, Laurie described her research group's work in analyzing these processes in capuchin monkeys.  The monkeys were trained to use metal washers as "currency".  They could use the washers to "purchase" commodities (apples or grapes) in various combinations.  In each instance, it appeared that the monkeys were making purchase choices/decisions not unlike those that humans make in many financial transactions.  Monkeys and humans share a similar characteristic of loss aversion, no matter the absence of a clear logic in making these decisions; the choices therefore appear irrational.  Despite the fact that we are evolutionarily quite removed from capuchin monkeys, Laurie's research shows that we share some basic cognitive patterns that are not a function of acquiring language and other skills. I am certainly not doing justice to what she spoke, nor the interesting ensuing discussion, so I recommend you view the footage when I post it, if you were unable to attend the session.

Thank you once again Laurie.  Thanks also to all those who attended, and to the Spencers for opening Cranberries' doors to us.

Click this link to view the Alan Alda hosted PBS special "The Human Spark",  that Laurie referred to during the discussion - http://video.pbs.org/program/1356407145/

November 22, 2009

Not a WIMPy afternoon at all

Tilde Café discussions seem to be almost inextricably linked to good weather! And there is always a group of enthusiasts who come in from the fine weather for an indoor discussion on a wide range of topics. 

Daniel McKinsey from the Department of Physics, Yale University had the rapt attention of café attendees on the afternoon of Sunday November 22, 2009, when he told us a little about his research in the area of dark matter, in language that everyone could understand.  After giving us a thumbnail sketch describing various components and particles of the largest thing known to us - the Universe - and why there is something called dark matter, he told us about dark matter particles yet to be detected and defined, such as WIMPs and MACHOs – Weakly Interacting Massive Particles, and Massive Astrophysical Compact Halo Objects.  Apropos acronyms for such particles! 

We learned that as we navigate our daily routines we are constantly bombarded by all kinds of (mostly benign to life) particles - tens of thousands of them per second - all stronger than WIMPs. Consequently, to detect a signal from WIMPs, one has to go deep below the earth’s surface, in mines and caves where all the noise from particles above ground is negligible.  What’s more, detection of these particles requires design and development of very precise, sophisticated and exquisitely sensitive equipment, which eventually finds use above ground too, in fields like medicine and environmental science. The afternoon ended with an interesting scientific and perhaps even partly philosophical discussion about the center of the Universe, its expansion, and the fundamental questions about mass, matter and motion.

Thank you again Dan! 

November 3, 2009

Family jewels stored in the form of molecules**

Approximately two thousand founders!  That’s the likely number of humans responsible for the diversity we see in the six billion humans inhabiting earth today.  A sobering thought that Himla Soodyall left us with.  Himla was the first international discussion leader at the café and kept the group absorbed in a topic that brought together threads from previous café discussions led by Tom Pollard, Michael Donoghue, Caroline Zeiss and Nayan Chanda. 

In the space of an hour several topics pertinent to genetic ancestry were addressed – including where the oldest archaeological records of modern humans exist and how they correlate with the representation of the oldest living DNA samples; what information mitochondrial DNA can give us; the information that the Y chromosome can provide; reaction to the unexpected findings of one’s genetic ancestry (visit this link for a short video clip Himla showed us at the end of the afternoon, arising directly from her work); ongoing efforts to address the controversy regarding the fate of Neanderthals (the first draft sequence of the genetic map of a Neanderthal was completed in conjunction with 454 Life sciences right in our backyard in Branford!); was there any exchange of genetic information between modern humans and Neanderthals; and much more.

Thank you Himla!

** Taken from the lyrics of Double Talking Helix Blues by Joel and Ira Herskowitz - superb way to introduce DNA and concepts of hereditary etc to elementary school kids.

September 22, 2009

A big thank you to Nayan Chanda who engaged us with a fascinating story of how coffee made its way out of Africa and into the world, from the very area that we can trace the origin of modern humans. There were a few challenges we had to contend with at the start of the afternoon because of cameras and microphones (these will be obvious when you view the soon to be posted video clips); however, thanks to Nayan's superb reconstruction of the story of coffee's migration across the world it all came together very nicely.

His presentation was peppered with all kinds of wonderful information regarding coffee-related terms too, for example, few of us knew that the mocha you order in a coffee shop is named after a major early port in Yemen from where coffee was traded.  

Click here to download the five page handout that was distributed at the cafe.

Thanks very much, Nayan!

June 6, 2009

The Platypus

by Ogden Nash

I like the duck-billed platypus

Because it is anomalous.

I like the way it raises its family

Partly birdly, partly mammaly.

I like its independent attitude.

Let no one call it a duck-billed platitude.

I think this poem by Ogden Nash sums up quite nicely this afternoon's café!

Caroline Zeiss's description of where the platypus sits in the context of evolution of species and the several mass extinctions that have occurred over the life of the earth, reminded us of two earlier discussions: Tom Pollard's café on evolution, and Michael Donoghue's on biodiversity.  Over the course an hour of a lovely spring afternoon, she gave us very interesting information (her handout will be posted on the café website). For example, did you know that a baby platypus is called a "puggle"; or that there are three classes of mammals (i) marsupials like the kangaroo (ii) placentals - like us and the majority of mammals and (iii) monotremes - egg laying mammals like the platypus?  Among still other things she described, was the importance of the eye in tracing evolution. Makes you look at life on earth with a whole new perspective!

If you were unable to attend the café, you can check out the video when I post it on the café web site, most likely next week.  I will send out an e-mail to alert you.

Thank you all for your support over the first season of Tilde Café's discussion series. We will meet again on September 19, 2009.  I will send out an e-mail a few weeks before that, with a flyer attached.

Thank you again, Caroline, for a very enlightening afternoon.

May 9, 2009

Biodiversity and Global Changes

A big thank you to Michael Donoghue for a very engaging conversation on “Biodiversity and Global Changes.”  He shed light on many aspects of biodiversity that one often does not think about, not the least of which is the vast number of species that inhabit this planet and how fast they are disappearing.  Among the many things discussed were how humans are contributing to the loss of biodiversity and the tangible impacts of this loss.  We also talked about ways in which we could all help to reduce the rate of loss of species and how we could contribute to improving the environment and thus the habitat for native species.

For more information in this regard specific to Connecticut, Michael pointed out the following url:

http://beta20.ctearthnet.org/inquiry/cten_home_public.php

By the end of the afternoon, it seemed we had recognized a few common threads running through the café discussions.  The thread between the talks relating to ecology, evolution, antibiotics and biodiversity seemed to slowly take form.  There are other common threads, but I’ll let them weave themselves into the fabric of the café as we move forward.

The next café will be on June 6, 2009, with Caroline Zeiss discussing “The platypus: a vestige of the past.”  You will receive the flyer soon.  I will also let you know when the current café video is posted on the café website and when it will be available on BCTV.  All previous café recordings currently available on the café website.

In closing, a quote from E.O. Wilson: "The one process now going on that will take millions of years to correct is the loss of genetic and species diversity by the destruction of natural habitats. This is the folly our descendants are least likely to forgive us."

April 18, 2009

Dark Matter and Dwarf Galaxies

Although the weather has decided to compete with the science café of late, it did not succeed in luring away more than a few previous attendees this past Saturday!  There are always new faces too and this was no different when we learned a little about what constitutes dark matter and dwarf galaxies from Professor Marla Geha.  She opened a window for us that we barely knew existed and of course that resulted in many questions and an interesting discussion.  It is tempting for those of us who know nothing about this particular topic, to launch into a series of puns but I will desist!  

The afternoon was dedicated to a dear friend of mine, Kalpana Reddy, who passed away quite suddenly and through an extraordinary set of terrible circumstances, only 13 hours before the café.  She was an artist not a scientist, and yet I know she would have really enjoyed the discussion on dark matter and dwarf galaxies.  Indeed, this is what the Tilde science café strives to do - engage non-scientists and scientists alike.

March 28, 2009

I think those who came to the cafe this afternoon were lucky twice over -  the weather was absolutely wonderful with just a hint of a cool breeze and temperatures around 10 degrees Celsius; just right to come in to Sweet Bears for a cup of tea or coffee and an excellent presentation by Susan Baserga on "Antibiotics: past, present and future."

Among other very interesting things about antibiotics, we learnt that Yale New Haven Hospital (at the time Grace Hospital, I think) was the first to administer penicillin to a civilian!  Right in our backyard.

I suspect none of us who were there will ever forget Susan's "show-and-tell" of how proteins are made in cells, replete with hamburger buns as ribosomes, and Twizzlers, carrot sticks and celery as RNA, amino acids and peptides!  For those who missed the afternoon, I will send out an e-mail when I post the video clips and also when BCTV is ready to broadcast the afternoon.

Thank you so much Susan for a fantastically informative hour!

February 28, 2009

"Quantum Mechanics: does anyone get it?"

What a fantastic response from the community!  There was standing room only for Shankar's absolutely riveting conversation on quantum mechanics. This strengthens my conviction that more people than we realize are keen on hearing about science.  I was dissuaded by a number of people when I said I planned to have a representation of all the sciences at the cafe; "very few people will want to hear about physics" was not an uncommon response!  Clearly, based on the turnout yesterday, that was very far from reality.

Many thanks to Shankar for making time to come and talk to us about a topic that very few of us have an opportunity to hear or read about.

I know several people left the afternoon feeling better informed about what engages physicists!

January 24, 2009

"Darwin's 200th birthday: how evolution helps us understand life on earth."

Thanks to all of you who attended this afternoon's presentation by Tom Pollard.  For those who were unable to attend, if you like you can catch it on BCTV - starting January 30 (check program listings for details).  Tom has kindly shared the chapter on evolution from his recent cell biology textbook, and it is posted on the Tilde website as a downloadable PDF file.  I would encourage everyone to take a look at it.  Excellent stuff!  Also posted on the website is a MSWord file of the handout he distributed.

December 13, 2008

Industrial ecology is NOT an oxymoron!

Professor Gordon Geballe was the inaugural discussion leader for Tilde Cafe.  This was probably the first time anyone present had heard of Industrial Ecology. The title for the afternoon asked if it was an oxymoron, since one does not really associate industrialization with ecology.  However, through the course of the afternoon, we learnt about this growing discipline and how one can become involved in it locally.

I'd like to thank all of you once again for braving the cold and coming out to Sweet Bears Dessert Cafe this afternoon to participate in the inaugural science cafe in Branford.  For those of you who were unable to attend, we have recorded the afternoon's proceedings and they will be aired very soon on BCTV, Channel 19.  I will post the details on http://sites.google.com/site/tildecafe/.

Please take a moment to respond to the survey (click on the url below), as it will help me in creating a list of potential discussion leaders.

http://www.surveymonkey.com/s.aspx?sm=iKqAGyPtS2iLB_2b4fS8yb9w_3d_3d