Author Archives: Carla Kidd

About Carla Kidd

I have a PhD in physical chemistry and am currently a postdoctoral scholar in atmospheric chemistry at the University of California, Irvine. I'm from the UK and moved to the USA with my husband in 2011. My work is definitely a challenge but life in the sunshine makes it a lot easier! I am on the whole a very positive person, an absolute necessity in a research environment where for the majority of the time nothing works, or you have no idea what anything means (maybe that's just me?). My friends would probably say I can be a bit 'spikey'. I call it passion. Let's just say there are a few things that drive me absolutely crazy. Maybe I'll share some of these with you at some point.

Can I be an astronaut when I grow up?

After seeing the video of Chris Hadfield, the Canadian astronaut singing David Bowie’s Space Oddity from the International Space Station I came across several funny videos of him describing life aboard the space station, from how you sleep, wash your hands, and even puke in space! It struck me that the Canadian Space Agency is doing an amazing job at harnessing the power of social media and hopefully this is inspiring the next generation to push the boundaries and get interested in science and technology (or to be astronauts, why not?!).

Hard to imagine that being an astronaut is an actual job!  Despite the fact that I’m sure I wouldn’t have the necessary smarts or character (I am also too short, phew!), I just can’t imagine ever being brave enough.  I wonder if kids still dream of being one? Or if the scaling back of NASA’s manned missions and the Moon landings and space race turning to distant memories has dulled the dream? Perhaps the next phase of commercial space flight will revive the excitement.

Image credit: NASA/JPL-Caltech/MSSS

Image credit: NASA/JPL-Caltech/MSSS

This got me to thinking about what will be our Moon landing? Man on Mars perhaps? Seems hard to imagine doesn’t it?  But imagine if it was possible. When I first heard that there were adverts looking for people interested in a one-way trip to Mars I was a little confused.  I understood that the possibility of a return journey was just too much of a challenge, but couldn’t believe any company (or agency) would be so upfront about the prospect of dropping some people off on Mars and then presumably handing them a suicide pill if they managed to get there alive.  I morbidly began thinking about who would apply…surely only people literally on a death wish.  They maybe wouldn’t be the best crew you could hope for!

But, that was my misunderstanding.  It turns out there is a serious plan.  Mars One, is a private company planning a manned mission to Mars by 2023.  It seems they are serious, over 80,000 people have already applied!  Imagine if you will, a seven month outward journey.  Seven months!  No water for washing, very closely confined with three other comrades.  Seven months! Then you land, just you four, and make your way to the pre-assembled (by machines) living quarters.  Imagine how crazy that would be.  The plan would then be that the original four will be joined in subsequent missions by more astronauts/immigrants in the years to follow, bringing more technology and materials necessary for expansion with them.  And so the colony grows…

Image credit: Mars One

Image credit: Mars One

The astronaut selection process is due to start this year, with them undergoing extensive Earth based testing over the several years between selection and launch.  Perhaps a sign of the times, but the plan is that the whole shebang will be televised, from astronaut selection, Earth based training, launch, transit, to landing and beyond.  As the company is a private enterprise, this will no doubt form a large part of the revenue required for the project.  Extraterrestrial reality TV.  This makes me slightly uncomfortable, especially when you think about the extreme challenges and dangers that would accompany this mission.  But I have to say I would definitely watch and I’m interested to see how this will all pan out.  Would I go?  Hell’s no!

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Nanobot twofers for cancer treatment

'nano nano!'

‘nano nano!’

In case you don’t watch as much bad TV as me, you may not know what a ‘twofer’ is. As the great Jessica Simpson says ‘everybody loves a twofer’ – a twofer being something that has two uses, for the price of one. She was of course referring to a top that is also a dress, or trousers that unzip as shorts…but this is about a medical marvel, a twofer that might just save you life one day.

Recently pulblished in the Journal of the American chemical society is a research paper describing the development of a rattle-structured multifunctional up-conversion core/porous silica shell nanotheranostic. Wow, that’s a mouthful! From now on lets call them twofer nanobots  – now let me break them down for you!

TEM images showing the core/shell structure

The nanobots are tiny balls of exotic rare earth mixtures made to be of a uniform size around 25 nanometers (human hair would be 60,000 nanometers) with a hole in the centre (core).

Next, a little gadolinium (Gd) is added before the balls are coated with a silica coating until they are around 50 nanometers in size. Each of these parts has an important part to play…

There are at the moment two major methods to treat cancer; (1) chemotherapy, where a drug is used to destroy the tumor and; (2) radiotherapy where x-rays are used to similar effect.

There are problems associated with both; chemotherapy requires high doses which causes a lot of pain as well as damage to non-cancerous cells. Some tumors such as hypoxic tumors can also have a very high tolerance to radiation.

What if you could transport the chemotherapy drug into the tumor directly? This would reduce the dose and damage to healthy cells. What if you could find a way to make hypoxic tumors respond to radiotherapy? What if, along with this you could also image the tumor?

Enter the nanbot twofer! No, wait now its a threefer (chemo, radio, imaging) are there no end to nanobots talents?!

The core is used to transport chemotherapy drugs into the tumor, the gadolinium allows the nanobot to be seen inside the tumor so you can image alongside treatment, the same drugs can be also be used as a radiosensitizer to improve the effectiveness of the radiotherapy. The silica shell is added to improve biocompatibility, so that it isn’t rejected by the body, and to make sure the nanobots dont clump together.

So that’s chemotherapy, radiotherapy and imaging in one smart nanobot, take that cancer!

I’ll take my science with a side of sun, sea and surf…

Sometimes you need to reset, to remember that you actually do enjoy your job, and take time out for inspiration.  This was one of those days…

2013-04-19 14.30.07

On a gorgeously sunny Friday, we got to go on an atmospheric chemistry themed lab tour of UC San Diego and the The Scripps Institution of Oceanography and it was pretty much the best (work) day ever!

Our day started in the Bertram lab, learning about experimental techniques for measuring reactions on sea salt aerosols.  Another cool experiment involved measuring how good different aerosols are at forming clouds – acting as cloud condensation nuclei.  They also described some of the challenges of getting ready for a field campaign such as the CARES campaign, or the GOAMAZON campaign.  These campaigns are organized years in advance and the deadlines are very strictly adhered to so once a commitment has been made by a group to participate, they absolutely must be ready on time.  This often involves building and testing new instruments, I know plenty about the pressures of working to deadlines but this stuff is on another level.

Then to the Thiemens lab, led by the super cool prof Thiemens – if you ever get a chance to attend one of his talks/lectures, you won’t be disappointed.  They work on very painstaking analysis of chemicals and rocks using radioactive isotope analysis.  As a result they are able to work out where things came from and how long they have been around.  They have made measurements  in the Arctic, the Antarctic, the Himalayas, even on meteorites from Mars and moon rocks.  We also heard  a little about Snowball Earth, something I had never heard of but I’m adding it to my reading list.

2013-04-19 11.15.28

An ATOFMS in the Prather lab UCSD

The Prather lab was full of the most kick ass machines – several aerosol mass spectrometers (ATOFMS) which the group actually developed and built themselves.  Take my word for it, this is pretty amazing.  They are using them to analyse aerosols in laboratory experiments and putting them on aeroplanes to monitor the real atmosphere.  They are even using one of them to look for markers in cancerous cells.  I loved that they all have names, like Shirley, Jake and Elwood!

What else? What else? Oh yes, the best part (don’t tell anyone but i’m thinking of changing career and becoming a deck hand), the Scripps Institute Hydraulics lab and Pier.  The lab contains a wind wave channel which is a 45 m long and 2.5 m wide channel filled with water.  At one end is a giant paddle that creates waves and at the other end is a massive fan that generates the equivalent of a mini hurricane to break the waves.  Luckily for us, the director of the institute was there and he cranked it up for us.  As you watch through the glass sides you see wave after perfect wave breaking right in front of you.  The wave channel is used to study in a controlled environment, what happens when waves breaks, from physics (how the energy of the wave is spent) to the chemistry (hooking up with UCSD chemistry scientists to measure what and how sea salt particles and gases such as carbon dioxide are exchanged with the air above the sea).  They also use it to test their very expensive equipment, before unleashing it, and quite possibly losing it, in a real storm in the middle of the ocean.

Last was the Scri2013-04-19 14.26.33pps pier, the perfect last stop.  Equipped with an array of weather monitoring systems and boats for sampling out at sea.  The icing on the cake, a leopard shark basking beneath us and a seal joining in with the surfers.  Good job UCSD, but talk about setting the bar high!

Make it rain up in here

Coming from the UK, I have an unhealthy fascination with the weather.  The never ending, will it – won’t it rain tomorrow? Will we get a day off school if it floods? Might it snow? Will we get snowed in? Talking about this is practically a national pastime, if weather worrying were an Olympic sport, we’d get gold every time.

Snowy Glynhir

Despite this early ‘training’ I only recently learned a little about how rain and snow actually forms.  An important lesson is that water can’t condense onto itself  to form rain droplets or snow flakes.  There needs to be a seed particle present and these seeds are known as aerosols.  An aerosol being a particle of one phase (such as a solid or liquid) suspended in a different phase (such as a gas).  So our seed particles are solid or liquid particles suspended in air.  The air we breathe is full of these aerosol particles.  There are thousands of types of aerosol in air, coming from both natural and man-made sources.  Examples might be tiny dust particles, sand, sea salt, bacteria, tree and plant emissions, car exhaust fumes to name but a few.

Aerosols are very difficult to study and understand because there are so many types of aerosols in the air, and they are constantly changing over time.  Despite the challenges, there is a lot of research being done on atmospheric aerosols because they are very important factors in climate change and our health.  But, back to rain and snow…

It isn’t just temperature that dictates whether clouds form as snow or rain.  Specific seed particles are good for making one or the other.  Dust particles from deserts for example, are known to be very good at nucleating ice (making snow).  Experiments in laboratories can be used to mimic the conditions leading to cloud formation and this is how a lot is learned about the snow or rain forming potential of different aerosols.  But, there are also plenty of field experiments where rain or snow is collected – on the ground or by flying aircraft through the clouds and collecting samples – and the non-water components analyzed to determine what the seeds were.

A good example is the CalWater field campaign which studied aerosol impacts on clouds and precipitation over the course of 3 consecutive winters In the Sierra Nevada.  They found that during all major storms desert dust and biological residues were the most common seed particles.  Using a variety of techniques including chemistry experiments on the ground, satellite data tracking the aerosols, measurements from aircraft in the clouds and detailed weather tracking the scientists were able to trace the dust and biological aerosols leading to increased snowfall to deserts in the Middle East, the Sahara in Africa and even as far afield as China*.  It’s amazing to think that dust storms in Asia can affect the weather thousands of miles away.  I wonder who we can blame for all the rain in Wales?

image

Photos courtesy of Katy Jenkins of Glynhir Mansion (Proof that it doesn’t just rain in Wales)

For more info on CalWater see:

http://www.esrl.noaa.gov/psd/calwater/overview/calwater1.html

*Science 339, 1572, 2013

Here Boy!

image    You know how it is when someone says that they won’t believe in evolution because you can’t show it happening? That really drives me nuts! There is so much evidence out there, you know they really mean that they don’t want to believe in evolution no matter what. Very well, there is nothing I can do for you.

But, for those who are interested, I find the domestication of the dog a fascinating example.  It really is evolution happening practically before our eyes. Ok, over the last tens of thousands of years, but that’s just the blink of an eye. So dogs as we know them, in all their variety evolved from wolves. It’s probably more correct to say that modern dogs and wolves share a common ancestor but I’m not an evolutionary biologist so I’m going to simplify things and say they evolved from wolves. And that recent experiments by some very clever geneticists have shown that dog domestication and the human diet are closely related.

It isn’t clear exactly when dogs as we know them came to be.  There have been bones found, of dog like creatures as old as 30,000 years.  Genetics tell us they have been around for at least 10,000 years and remains of dogs and humans together have been found and aged in this timeframe also.

There are a couple of theories of how dogs began.  There must have been a strong driving force to drive this evolution from wolf to puggle.  One possibility is that early humans captured wolf pups and used them for guarding and hunting.  It would figure that the humans would get on best with the friendlier of these captured wolves (rather them than me) and if the friendlier more docile wolves were encouraged to breed then you have the beginnings of a new wolf breed which has a better temperament than it’s ancestors. Another theory (I like this one best but should stress this is not my area of expertise) is that when humans changed there lifestyle from a hunter-gatherer nomad to settling in permanent sites, wolves would have had an extra, previously unheard of food source…the dump.

At this time, the dawn of the agricultural revolution, humans had a diet change which involved eating more starch, from the veggies and grains we were learning to grow.  Some of these would find their way to the community dump and some smart wolves would be there with open mouths.  Hanging out at the dump would after all be much more fun than catching dinner yourselves.  It is possible that these ‘scavenger wolves’ are the ancestors of modern dogs, again, the less aggressive and more able to live with humans they were, the better off they would be.  Driving the selection of all the features of Fido that we love so much.

Back to those clever scientists.  They were able to study the entire genetic code for 14 different dog breeds and compare this with the code from wolves.  This is no mean feat because wolves and dogs are genetically speaking, so similar.  Remember we are 97% genetically similar to mice*.  They found some pretty remarkable things.  First, that dogs and wolves differ in the genes responsible for behavior and thinking.  I know that sound obvious, but to actually see it in the genes is amazing, at least in my humble opinion.  Second and most important, they found that genes responsible for the ability to digest starch is only present in domestic dogs and not in wolves.  Which seems to support the idea that domestication and the agricultural revolution are linked.  It’s also very interesting that human and dogs both had a parallel genetic change or evolution when starchy foods became more available.  We go back a long way, us and the mutts.

* I made this number up, but I’m sure it’s something like this

Reference: Axelsson et al., Nature. 495. 360. 201

Loyal Bees get a Bonus Buzz

Photo courtesy of Katy Jenkins (The Glynhir Estate)

    A new study shows that certain plants are able to tailor the chemistry of their nectar to increase their attractiveness to honeybees. Plants have a wealth of chemical weapons at their disposal. The arsenal is usually used to fight off hungry insects but new research shows that they can also use chemistry to attract pollinators like the busy bee. In this case, caffeine is the chemical of choice. Caffeine was detected in the nectar from several varieties of Coffea and Citrus. These plants are also known to produce more fruit and seeds when pollinated by bees rather than another pollinator.

The scientists were able to train the bees (I’m imagining a bee bootcamp) to respond to a cue using a reward system. The bees were rewarded with sugar syrup or sugar syrup and caffeine. They found that the bees responded better to the caffeinated syrup, that they preferred it. Even better, the bees memory of where the caffeine was got better with time. The caffeine dose had improved their memory.

The weird thing is, bees don’t even like the taste of caffeine! In high doses, it repels the bees, higher still it would kill them. So the plants are able to tailor the mixture just so, to give the bees a nice buzz but not to drive them away, or worse… What do the plants gain from this? Bee loyalty of course. Making the bees more likely to visit that plant variety over another and improving its chance of survival. As for us, we know that caffeine in low doses is good for a boost but it also improves memory too.  I’m off for a brew.

Reference: Wright et al., Science. 339. 1202. 2013. 

Photo courtesy of Katy Jenkins (The Glynhir Estate)