Ever feel like your on a sinking ship? Just one of those days where everything seems to be going wrong, the weather, work, writing…
Wait – I’m not here to write about exististential crises. I want to write about sinking ships. And bubbles.
The Bermuda triangle seems to be one of those unresolved mysteries. In this triangle-shaped area near Florida, an unusual high number of ships have reportedly sunk to the bottom. Is it due to paranormal activity? Aliens? Magic?
It might just be due to methane bubbles – there are flatulent cows at the bottom of the North Atlantic Ocean.
Just kidding. There are no cows there.
There are large areas of methane hydrates. This natural gas cause periodic methane eruption, causing bubbly regions in the ocean. And it turns out that bubbles can cause ships to sink.
Bubbles cause the average density of the water to decrease, and when this is too low (lower than that of the floating object), an object that would normally float, would sink. It sounds a bit like the opposite of a fluidized bed, where a solid is turned liquid, making things float on sand.
Methane bubbles are one of the possible reasons for the mysterious disappearance of boats in the Bermuda Triangle. Though violent weather and dramatic, exaggerated reporting are probably more to blame.
However, let’s not send any cows to the bottom of the ocean, just in case.
Quand le doigt montre le ciel, l’imbécile regarde le doigt.
For those who don’t speak French, or have never watched the fantastical modern fairy tale that is Amélie [in that case, stop reading and go watch it], this translates to: “When a finger is pointing up to the sky, only a fool looks at the finger.”
It’s not just fools; most animals would look at your finger and not the object that is being pointed at. Apparently, it is a rare trait to understand what pointing means.
Even though it is often considered rude to point – I surely remember being told that it was – it turns out that pointing is something very human.
What’t the point?
According to Michael Tomasello (Duke University), it all starts at the young age of 9 months.
Sometime between being 9 and 12 months old, infants start pointing at things that they want or find interesting. While it is possible for some animals (we’ll get to that later) to look at the pointed-to object, infants understand that there is more to it.
There are different reasons to point. You can point to things that you want, like a cookie or a toy. You can point to things that you find interesting, like a dog or a toy. You can point to things that remind you of a shared experience, like a train or a toy. I guess I really like toys.
At a very young age, infants understand that pointing can be used to draw attention to something. The fact that pointing starts exhibiting itself at such a young age is an indication that it is – at least for some part – an evolved trait rather than learned. By creating a connection, and shared experiences, with another person, you start automatically pointing to things that refer to that shared experience – even before language is developed.
No matter where you travel, what language you speak, how old you are, pointing is universal. We understand that something pointed at is a request to share attention.
Get to the point
So toddlers know that when we point at something, we want them to look at it. While it is possible to teach chimpanzees – our closest cousins in the animal kingdom – to look at the object that is pointed at and to use pointing as a means to communicate, it takes a lot of conditioning. Most chimps fail the “pointing test”.
Dogs, however, pass easily. It seems that living with humans for centuries (millennia even), has led to dogs evolving to understand what pointing means.
Dogs have long been the prime example of understanding what pointing means. Our second-favorite-pet, however, was long considered to be untrainable and aloof. Until recently, when new studies have shown that cats can pass the pointing test – if they care to participate…
But cats that have a good connection with their owner, and spend a lot of play time with them, often have the ability to not be the fool, and look at the object rather than the finger. It seems that again, shared experiences is crucial for pointing to work.
In any case, next time someone tells you that it’s rude to point, tell them that it’s human to point.
Next week is time for the local Jazz Festival, and to prepare I switch my background music back to Miles’ iconic album. In addition, I have been made aware that I seem to be making blue my go-to color. On a slightly related note, it turns out that blue is a very hard color to make.
I spy, with my little eye, something blue…
It seems weird that blue would be hard to make. It’s so prominent in nature. The sky is blue. The ocean is blue. Blue jays are blue. Blue eyes are blue.
But as it turns out, blue pigment is very rare. Butterflies and birds with a blue color aren’t blue because their wings or feathers contain blue pigment, but because of nanostructures that reflect and diffract light in such a way that interference amplifies blue wavelengths, while cancelling out the others.
A blue pigment however, absorbs all wavelengths except blue. Light absorption occurs when a photon supplies an electron with enough energy to jump to a higher energy band. As red light has the lowest energy, only electrons with a narrow energy gap can be excited. Only a few molecules have the right structure for this to happen. Absorption of red light is crucial for a blue pigment, and therefore it’s a rare thing.
Out of the blue
Because of their natural rarity, the design of synthetic blue pigments is of high interest for science and industry. The bluest blue was created by accident, by Mas Subramanian, a solid state chemist who wanted to create a material with the combination of electronic and magnetic properties for microchips. One of his ideas didn’t lead to anything particularly useful for fast computers, but it was very blue.
The blue dream
Where did this quest for blue originate? Blue is most people’s favorite color; it symbolizes depth, stability and serenity; and as it is the color of the sky and the sea, painters love it. True blue flowers are non-existent (violets are purple, people), even though horticulturists and scientists have tried endlessly. And even though blue food is unconsciously associated with toxins and spoilt food, some scientists’ life goal is to create true blue food coloring, rather than current food coloring that seems more green.
While artists, foodies, and flower lovers dream of the truest blue, I’ll go back to some sweet tunes and feeling slightly melancholic. I mean… Blue.
It goes without saying that 3D printing is cool*. The ability to think up any three dimensional structure, design it in a 3D design software and have it materialize blows my mind. Granted, I’m making it sound like it’s a very easy and fast process and I know that’s often not the case, but I also know that for a lot of engineering and physics laboratories, the ability to relatively quickly print a model or prototype for anything is extremely useful. In addition, it’s an amazing educational resource. You can print model organs, molecular structures, planets, … and have something physical to show or throw around during a science demo.
Just to name a few reasons why 3D printing is cool.
What is possible even cooler is the potential of printing tissues and organs. And now, for the first time according to a group of researchers in Tel Aviv, it has happened: a complete 3D heart was printed.
They started with some cells isolated from a sheet of fatty tissuefrom a human patient. These cells were reprogrammed to what’s called pluripotent stem cells. Pluripotent stem cells have the potential to give rise to many different cell types , depending on the biochemical cues they get – for example by changing the formulation of the culture media, which contains nutrients, hormones and other components to “feed” the cells.
In this case, the cells were driven towards being heart muscle cells and blood vessel cells. By mixing these cells with a personalized hydrogel, consisting of collagen (remember, from the reindeer eyes?) and glycoproteins (proteins have a sugar molecule connected to it), the researchers created a “bioink”, a material that could be used to print cardiac tissue in the same way a 3D printer prints 3D structures using a plastic “ink”.
While the 3D printed heart – currently around the size of a rabbit’s heart – cannot beat yet, the possibility to be able to print custom organs, starting from a patient’s own cells and therefore eliminating an immune response, is of major importance for medical applications. To enable heart function, the heart cells would have to be taught how to contract in an organized manner, and create a beating heart.
Beating has already been achieved in heart organoids. Organoids are little mini-organs grown in a petri dish, that mimic the organization and function of an organ in a living organism. The difference between 3D printed organs and organoids, is that organoids are allowed to form their own structure and cell types, driven by the media cocktail they are given, while 3D printing positions already differentiated cells in a 3D scaffold. Heart organoids, starting from one or a few reprogrammed cells, grow into structured groups of cells that spontaneously start beating.
These organoids, however, don’t really mimic the structure of the heart unless you “force” structure by growing these mini-hearts in a mold, basically geometrically confining the cells to form a predefined structure.
A model of a pumping heart was developed last year, creating an in vitro biomimetic system that could help with drug discovery and studying cardiac diseases. While it doesn’t look as much as a heart as the 3D printed one developed by the Israeli research group, it’s still pretty amazing to watch this little blob of tissue beating under electrical stimulation:
In any case, I hope to see a combined version of all of the above: a 3D printed, functional heart. Nevertheless, this first (though debatable if they actually were the first) 3D printed heart is pretty awesome and has a lot of potential applications in medicine and clinical research. Not to mention that it looks pretty cool:
Noor N., Shapira A., Edri R., Gal I., Wertheim L., Dvir T. 3D Printing of Personalized Thick and Perfusable Cardiac Patches and Hearts. Adv. Sci. (2019), 1900344. https://doi.org/10.1002/advs.201900344
Ma Z., Wang J., Loskill P., Heubsch N., Koo S., Svedlund F.L., Marks N.C., Hua E.W., Grigoropoulos C.P., Conklin B.R., Healy K.E. Self-organizing human cardiac microchambers mediated by geometric confinement. Nat. Comm. 6 (2015), 7413. https://doi.org/10.1038/ncomms8413
Li R.A., Keung A., Cashman T.J., Backeris P.C., Johnson B.V., Bardot E.S., Wong A.O.T., Chan P.K.W., Chan C.W.Y, Costa K.D. Bioengineering an electro-mechanically functional miniature ventricular heart chamber from human pluripotent stem cells.Biomaterials 163 (2018), 116-127. https://doi.org/10.1016/j.biomaterials.2018.02.024
*Sudden realization that most (if not all) of this blog is me saying “Hey, did you hear about this science thing, it’s really cool!!”
A few weeks ago, I went to a public lecture – attractively named “Wine Down with Science” – organized by UW Medicine and I’ve been trying to tell people about it ever since.
The first problem is that the topic of the talk is one of those words that I’ll always just struggle to pronounce on the first go:
I went to the event not knowing what it was going to be about. I was already sold when I read it was a public lecture about some ground breaking research; any excuse to listen to science in a more informal setting. Turned out, it was good of me to go, because it was sort of about biophysics and biophysics is sort of my jam.
So what is the *insert long word here again*?
Proprioception you mean? According to the event announcement, the lecture title was: Out of Your Mind: The Inner Workings of Your Mysterious Sixth Sense. So proprioception is about seeing dead people?
Nope. In reality, proprioception is our ability to be aware the position and movement of our body and its parts. Not having proprioceptive abilities is one of the reasons that man-mimicking robots fail at a lot of seemingly basic tasks. They have no internal feedback system to tell them how their parts are positioned or moving with respect to each other, making benign tasks hard to do.
With proprioception, we know exactly how are body is positioned: whether our arms are bent, our feet are flexed, our eyelids are closed (okay, there are other ways to tell). And that without having to look those body parts. There are some known cases of people losing their sense of proprioception and it causes paralysis (if you have 10 minutes to spare, you should really check out this video about a man who lost his sense of proprioception but taught himself to walk using visual cues instead).
How can we study this proprioception thing?
This is where it gets even cooler. The lecturer – John Tuthill – explained how in his lab, they use a clever combination of lasers, genetic tools, virtual reality, and fruit-fly-treadmills to understand how proprioception works.
By making a fruit fly run on a floating ball, and surrounding it with screens, they can trick the fly into thinking it’s strolling somewhere outside and track the neuron activity during movement. Using a laser, they can turn off the proprioceptive neurons very locally (using something called optogenetics, but that’s for some other time). For example, if by blocking proprioception in one of the fly’s legs, i.e. stopping communication between the leg and the central nervous system, they temporarily paralyze that leg. After turning the laser back off, the fly trods on as if nothing has happened.
First of all, part of science is just understanding how things work. Knowledge for knowledge’s sake. But there are also some useful applications of this knowledge, such as helping people with movement disorders. And helping robot-designers to not make robots that seemingly stupidly fall over.
This talk was by John Tuthill, PhD, Assistant Professor of Physiology and Biophysics. His work is really cool. Go check it out.
Occasionally, a colleague passes by my desk and says something along the lines of “Hey, did you know that *insert fun – usually science-related – fact here*?”
The other day, this exact thing happened:
“Hey, did you know that reindeer’s eyes turn blue in the winter?”
The question was prompted by the magnificent drawing of an octomoose (name pending) on the white board in our office. How the octomoose came about, is not that interesting a story, but I would want to share with you that we held a poll to determine the name of the 8-tentacled creature. My vote was for moctopus. I did not win (6 vs 3 votes).
So now that winter has come to an end, let’s talk about those weird reindeer eyes.
Discerningly, the first suggestions google search gave me when I typed in “reindeer eyes” was “reindeer eyes recipes”, which is just creepy; though actually clicking through reassured me that it was about chocolates and cookies (phew).
The struggle did not end there. The next page I found had a photo of a “summer reindeer eye” vs a “winter reindeer eye”:
Jackpot? Nope. The photo was photoshopped (quite obviously). Sigh. This is turning out to be a lesson in fact checking.
However, I was not chasing a myth. It’s still true that reindeer’s eyes change color from gold in the summer to blue in the winter. Proof of this is in a scientific paper (hurray for backtracking to the source) which features some very creepy photos of reindeer eyeballs:
The explanation to why this happens seems to lie in the reflective layer that sits behind the retina: the Tapetum lucidum. A lot of mammals have this layer; you might have noticed it when shining a light in your cat’s eyes (and survived to tell the tale). This extra layer helps animals see when it’s all twilight-y. It reflects light that passes through the retina, causing the light to pass through the retina twice, giving the light-detecting cells of the retina a second chance to detect any photos. When you see that yellow glow in your cat’s eyes, it’s the light reflecting right back at you off their Tapetum lucidum.
The next bit of eye knowledge you need to understand the changing reindeer eye color is the fact that pupils widen and shrink depending on how much light is available. Dilated pupils allow more light to enter the eye, and hence more photons can be detected by the light-sensing cells in the retina.
In the arctic winter – basically 3 months of darkness – the reindeer’s pupils are continuously dilated. The constant effort to keep the irises open, constricts the small vessels that usually drain fluid out of the eyes. This in turn causes a pressure buildup within the eye, which compresses the Tapetum lucidum.
The Tapetum lucidum is mostly made up of a protein called collagen. This fibrous protein is a hydrogel, an ordered mesh of fibers that absorb and retain fluid. However, when this mesh is compressed, the fluid is squeezed out (like when you squeeze a sponge) and the orderly rows of collagen fibers become more tightly packed. The type of light that is reflected by the Tapetum depends on the spacing between these fibers. When they are “normally” spaced, like in the summer, longer wavelength light (yellow) is reflected, giving the Tapetum a golden color. When tighter packed, blue wavelengths (which are shorter) are reflected, giving the reindeer blue eyes.
In short, in the months of darkness, reindeer’s pupils are permanently dilated, leading to swollen eye, leading to compression of the collagen fibers, changing the color that is reflected by the Tapetum.
Research is still ongoing, because even though the mechanism behind eye-color-change has been explained, the effect on eye function is still unclear. Perhaps this change in eye color changes the sensitivity of the eyes. And why do other arctic animals, who also live through months of perpetual darkness, not have this cool change in eye color?
However, one thing is for sure, Rudolph’s red nose cannot be explained by science. Yet.
The original source: Stokkan, Folkow, Dukes, Nevue, Hogg, Siefken, Dakin & Jeffery. 2013. Shifting mirrors: adaptive changes in retinal reflections to winter darkness in Arctic reindeer. Proc Roy Soc B http://dx.doi.org/10.1098/rspb.2013.2451
A few months ago, my friend Vale asked me to collaborate with her on a project. I remember it going something along the lines of:*
Vale: “So, I’m working on this project and was wondering if you wanted to be part of it.”
Me: “Yeah, of course.”
Me: “Wait, what is the project?”
Say “yes” and ask questions later
Though probably not valid for every situation, I knew that in this case, I would be fine to say yes before knowing what I’d said yes to. If you’ve read any of my other stuff, you know that I’ve done various “scicomm”** projects like developing a “Build a LEGO-microscope” workshop and organizing a lecture series called “The Science of SciFi”. These were both in collaboration with Vale (and occasionally other people). She’s also the one who got me into Bright Club!
It seems that we work well together. And working together on a new project (without even knowing what it was), sounded like a lot of fun.
By now, I (obviously) know what the project is. It all started with #inktober, an art challenge that challenges illustrators to draw something using the medium of ink every day for a whole month (can you guess which?). Vale took up that challenge, and made it even more of a challenge by deciding to bundle her illustrations in a book.
Every drawing is based on a scientist*** that she considers a personal inspiration and is linked to a word from the prompt list. She’d post the result with a short explanation of why she chose that scientist for that prompt. Sometimes they were pretty obvious (at least to me, of course “stretch” is about D’Arcy Thompson!), some rather funny.
And then I come in.
Inspired by her drawing, I write a short text to go along with it. Sometimes it’s an anecdote. Sometimes it’s a quote. Sometimes it’s a short story about the scientist’s life. I try to make it as informative, engaging, unique and fun as I can.
It’s kind of awkward for me to sit here and write about a book I’m involved in, trying to get it made, aka trying to get the campaign funded. Like really, really awkward. So I’ll only do it once****:
Every little helps. Pledging helps, obviously, but spreading the word does too. If you like science, engineering, and math; and if you like amazing art; and if you like stories (and if maybe you also like us)… please share our project and help us make this book a reality!
Both Vale and I have found inspiration in these scientists, and we have found inspiration working on this book together. Hopefully, it will inspire you too.
*end of sappy book promo – I’ll be back next week with the usual science, nerdiness and hopefully some “Eureka!”s*
*Severely paraphrasing. This was months ago. I might have also dreamt it but on the other hand, this project is happening so I guess that means the conversation happened too.
** or “science communication”, which is the umbrella term I use for STEM-related outreach, workshops, talks, and other similar activities.
*** in the broad sense of the word. They could be mathematicians, or engineers, or inventors. Creative STEM-people if you will.
**** on this blog, to be clear. My other social media channels will be swamped! Like, I actually really care about this project and am super excited and want to see it happen!
All of the art work shown in this post is by Valentina, and within the #inkingscience project.
It’s been the topic of a weighted discussion for quite some time, but today it has been decided: “Le Grand K” will no longer be used to define a kilogram.
“Le Grand K” is not a big box of Special K, but a platinum-iridium cylinder stored by the International Bureau of Weights and Measures in an underground vault in Paris that has defined a kilogram of mass since 1889. There are a few official copies, and many more copies, so each country has their own kilogram to calibrate to.
Last Friday (November 16th) the kilogram has been redefined so it no longer depends on a material object. Because a material object can be scratched, chipped or destroyed. Or stolen. Or accidentally thrown into the bin. And it can degrade – in fact, “Le Grand K” weighs about 50 µg lighter than its six official copies. You don’t really want to gold – ahem, I mean platinum-iridium – standard for weight to change in weight, right?
So now the kilogram will be defined based on a universal, unchangeable constant. Much better, I think you would agree. The constant of choice here is the Plank’s constant, a number that converts the macroscopic wavelength of light to the energy of individual constants of light. Representatives from 58 countries universally agreed on this new definition, so from next year, the kilogram will be constant forever.
The ampere (electrical current), the kelvin (temperature) and the mole (amount of chemical substance) have also been redefined. That means that all seven units in the International System of Units (S.I.) will be defined by universal constants:
unit of length
Originally defined as a 10-millionth of the distance between the North Pole and the Equator along the meridian through Paris, later as the distance between two scratches on a bar of platinum-iridium metal
Since 1983 defined as the distance traveled by a light beam in vacuum in 1/299,792,458th of a second, with 299,792,458 m/s being the universally constant speed of light.
unit of mass
Initially defined in terms of one liter of water, but since as a small ~47 cm3 cylinder stored in a basement in Paris.
Now redefined in terms of the Plank constant h = 6.62607015×10−34 J*s (J = kg*m2*s−2)
unit of time
Originally defined as 1/86,400th of a day
Since 1967 it has been defined as the time it takes an atom of cesium-133 to vibrate 9,192,631,770 times
unit of electrical current
Originally defined as a tenth of the electromagnetic current flowing through a 1 cm arc of a circle with a 1 cm radius creating a field of one oersted in the center
Now redefined in terms of the fixed numerical value of the elementary charge e (1.6602176634×10−19 C with C = A*s and second defined as above)
unit of temperature
The centigrade scale was originally defined by assigning the freezing and boiling point of water as 0 °C and 100 °C respectively. Note: absolute zero is the lowest temperature (0K = -273.16 °C)
Now redefined in terms of the Boltzmann constant k = 1.380649×10−23 J⋅K−1
unit to describe the amount of substance
Since 1967 defined as the amount of substance which has as many elementary particles as there are atoms in 0.012 kg of carbon-12.
Now one mole substance contains exactly 6.02214076 × 10^23 particles. This constant is known as Avogadro’s number*
unit to describe the intensity of light
Originally taken as the luminous intensity of a whale blubber candle in the late 19th century.
Since 1979 the light intensity of a monochromatic source that emits radiation with a frequency 5.4 x 1014 hertz and has a radiant intensity of 1/683 watt per steradian in a given direction **
So that was “this week in science.” I’ll leave y’all with a related joke:
I’ve felt bad all week. Well, not really all week. And not really bad. I’ve felt a teeny bit guilty for joking that economic sciences is not really a “science”. The “soft” sciences (social sciences, economic sciences, psychology, to name a few) are too often ridiculed by practitioners of the “harder” sciences. I’ve done it too. Last week in fact, as I’ve just said.
Most of the “soft” scientists I know don’t really mind too much (yes, I have soft science friends, I *can’t* be an elitist), and they laugh along. But still, I wanted to bring a bit of nuance and perhaps a tiny apology,
especially since this years’ Nobel Prize for Economic Science was awarded for integrating climate change an technological innovations into long-run macroeconomic analysis. Two subjects that are kind-of STEM-related.
Therefore, no matter how you might be willing to rank them, something can be considered science (from the Latin word scientia – “knowledge”) if the scientific method is applied.
What’s this scientific method?
The scientific method is a way to approach a problem or question by following this – or any similar – flowchart: *
Very briefly and with an example, these are the steps you’d follow:
Observation This can be anything you observe. Example: People seem a lot friendlier here in [town A]. When I pass people on the street, people smile at me more than they did when I was in [town B].**
Question From that observation, you can formulate a well-defined question, a problem you would like to know the answer to. Science is simply the pursuit of knowledge, you know. Example: Are people more friendly in [town A] than in [town B]? (if friendly is defined as “smiling at people on the street”)
Hypothesis You probably have a little bit of data (from your observations) that allow you to formulate the answer you would expect. This possible answer is something you can test: is what you assumed true or false? Example: People in [town A] smile more on to passers-by than in [town B]
Experiment Now it is time to collect your data. Example: I’d go to [town A], walk around in the center for – say – 30 minutes and count how many people I pass on the street (and actually make eye contact with) and how many people smiled at me. I’d then do the same for [town B].
When you have collected all your data, sit down and perform some analysis. Usually, statistics are the thing to apply. Example: I’d calculate the ratio of smiling people in each town, let’s say 17 out of 59 (29%) of people smiled at me in [town A], while 34 out of 81 (42%) people smiled in [town B].
Conclusion Example: I reject my hypothesis; people in [town A] are not friendlier than people in [town B]. This last step is checking if my hypothesis was correct (it wasn’t). Rejecting the hypothesis means I can go back and change my hypothesis and start again. If my hypothesis was correct, yay – I’ve done science!
Well, in reality, there is even more to it (both for rejecting and accepting an hypothesis).
In this example, there are many faults. Was my definition of “friendliness” correct? Were there factors I didn’t account for, like a bit of spinach between my teeth that caused more people to smile (or laugh) at me? More importantly, if I repeat the experiment, do I get the same result***? Was my experiment well designed; maybe there are better ways to test this same hypothesis?
Back and forth and back and forth and back and forth again.
Science is a very iterative process. Hypotheses are constantly being reformulated and retested. It is actually impossible to be 100% a hypothesis is true. The real science is when you try every which way to disprove your hypothesis. It is after a lot of back and forth and iteration, that a theory about something can be formulated. But you should know that in the scientific lingo, a theory has nothing to do with guesswork. It is the result of several repeats of observations and experiments that are generally accepted as reliable accounts of the world around us. ****
Scientist vs. engineer
I’d also like to note that science and engineering are quite different things. A scientist wants to know how things work while an engineer kind of just wants to make things work.
For example: engineers built the large hadron collider; scientists use it to study elementary particles.
Though it should be said that a lot of scientists have a bit of engineering in them, and vice versa.
* Listen to Niel Degrasse Tyson explain the scientific method using a whipped analogy below.
** I just know that this is just because I look funny.
*** Typically, at least three repeats showing the same conclusion are necessary to accept a hypothesis.