Julia Santos

Mar

2022

On non-thermal desorption and baked goods

In the beginning of the month I have had the opportunity to visit the oldest city in the Netherlands, Nijmegen. Besides trying the exquisite local delicacy called marikenbrood, the supplementary purpose of the trip was to take part in experiments utilizing the Free-Electron Lasers for Infrared eXperiments (FELIX) laboratory. This facility is part of Radboud University and, as the name implies, provides free-electron lasers that can be employed to all sorts of research. In our case, we wanted to utilize it to explore photodesorption processes potentially taking place in interstellar space.

According to chemical models, interstellar molecules should be largely frozen out onto icy grains during the early stages of star and planet formation. In fact, species such as CO and CO2 should be completely depleted in the gas phase at such cold and dense environments. The detection of gaseous CO in dark clouds and the midplanes of protoplanetary disks thus implies that some sort of desorption must take place, efficiently transporting these molecules from the surface to the gas.

Given the low temperatures associated with these clouds (~10 K), thermal desorption should be negligible. There is simply not enough thermal energy available to desorb the chemical species from the sticky icy surfaces. Therefore, non-thermal processes are paramount to explain astronomical observations of many molecules. Many different pathways for these processes have been suggested so far. Some of them are:

Through photons impinging on the ice
Through the impact of cosmic rays, which can result in desorption either by direct heating of the ice or by exciting and ionizing species along its path that subsequently release chemical energy
As a result of exothermic reactions taking place in the ice

Both theoretical and laboratory approaches have been extensively applied to study non-thermal desorption, which has been a constant topic of discussion due to its important implications on the chemistry of shielded interstellar regions. However, there are still many questions to be answered regarding the specific mechanisms through which these processes take place. So it goes without saying that I am very excited to be able to perform experiments so different than what I routinely do, and to explore this particularly hot—or, should I say, non-hot—astrochemical topic!

Jan

2022

What I learned from the peer-review process (so far)

Positive referee reports are all alike; every negative report is negative in its own way.

Yesterday I submitted the first paper of my PhD. As I mentioned in my last blog post, it is about my first project as a doctorate student, on the formation pathways of methanol in interstellar ices. This was also my first experience with writing an article on laboratory astrophysics, which gave a fun experimental spin to my writing modus operandi.

But this is not the first time I go through the peer review process. Shortly after I finished my bachelors and started my masters, I submitted my first first-author paper on a project I had been working on as a continuation of my undergraduate thesis. At the time, I was so exhilarated by the fact that something I did was—hopefully—going to be part of the scientific literature that what came next could not be described as anything less than a bucket of cold water.

Among the three referee reports received, one did not recommend the paper for publication. Not only that, but its content displayed the quintessential negative-and-borderline-hostile criticism we have all heard scary stories about. My giddy anticipation was instantly converted into disappointment, and the positive feedback of the other two referees was not nearly enough to assuage my hurt feelings.

Despite the unpleasantness of the situation, one must persevere. After three more reviewing rounds—at this point largely fueled by a spiteful belligerence worthy of George Constanza—the paper was finally accepted for publication. The fight was over: we won!

Weeks passed peacefully until the final version was published. In the meantime, I had not but once read the manuscript in question (for the proofreading, which we all know it’s a different kind of reading). Then, once it was out, I read it again. And as I went through it, it became increasingly clear to me how the comments of the infamous referee helped to improve the work. It is not that I hadn’t noticed this while working on the reviews, but it was partially obscured by my understandably negative feelings about the report. Although it would have been appreciated if they had chosen a different tone, their contribution indeed elevated the paper.

This experience taught me an important lesson about humility, maturity, and patience. Humility to recognize when someone notices something you did not, maturity to deal with scientific criticism without taking that personally, and patience to let go of hurtful and unhelpful comments.

Since then, none of the other peer-reviewed articles I published resulted in such an involving story, for which I am very thankful. Naturally, I hope things can go smoothly with this next one too. But, if it doesn’t, I can look back at this text and remember the Big Picture.

Dec

2021

A quick look into my research

Regardless of wether in the broiling, effervescent December of Rio de Janeiro or the crisp and cosy dutch winter, I’m amazed to see how some universal end-of-the-year customs prevail. The nights illuminated by warm Christmas lights, the joyful anticipation for the year to come, and especially the mellow scents of roasted chestnuts, cinnamon and baked goods give a pleasant sense of belonging no matter the geographical location. That’s why in my mind December asks for pie, and especially apple pie. Thankfully, Sagan, the ingredients to make homemade apple pies can be easily acquired in any local market, and we do not need to first invent the universe. But—let me tell you this—that is something I would like to explore.

And with this sweet introduction I wanted so bad to put on paper I can segway into the actual topic of this post: my research work. Alfie’s last blog post inspired me to share a little bit more on the research I’ve been working recently and the main topic I want to tackle during my PhD. Or, at least, what my plans are for the near future, since three and a half years are simultaneously a heartbeat and an eternity when it comes to science.

Long story short, I am fascinated by the chemical lavishness associated with star- and planet-forming regions, and how their chemical inventory evolves in complexity, ultimately leading to the building-blocks of life. In my PhD, I want to explore this connection by studying in the laboratory the chemical reactions that happen in interstellar ices, and how those can lead to the formation of complex organics and prebiotic molecules.

Right now, we are finishing-up a project on the formation of methanol (CH3OH) in space. This molecule plays an important role in the chemical network of the interstellar medium, and that’s why it’s important to understand its chemistry in as much detail as possible. Accordingly, we have performed experiments in the ultra-high-vacuum setup SURFRESIDE3 in Leiden to create analogues of the interstellar ices rich in CO and to see how it interacts with hydrogen atoms to form methanol. In the end, we were able to employ a quantum-mechanics phenomenon called the kinetic isotope effect to assess the contribution from different chemical routes to forming CH3OH.

Nov

2021

Dez perguntas para uma astroquímica na Holanda

Recentemente, eu superei minha implicância (bem justificada, diga-se de passagem) com tudo relacionado à indústria da moda e resolvi assistir um dos famosos vídeos de 73 perguntas da Vogue. Escolhi a entrevista com a primorosa Olivia Colman, o que obviamente minimizou consideravelmente a probabilidade de ter sido uma experiência negativa. Gostei tanto, inclusive, que me veio a vontade de participar de algo semelhante. Como a minha nomeação ao Oscar, porém, ainda está sendo deliberada pela Academia, penso que quase uma centena de respostas beira o limite da empáfia.

Numa alternativa mais comedida, minha amiga e breve membro do InterCat, Luise Butzke, produziu um vídeo com apenas quinze perguntas sobre sua pesquisa e a vida na Dinamarca. Para dar continuidade à iniciativa da Luise, e para poder me ufanar inofensivamente do meu tópico de estudo — eu sou, no fim das contas, uma acadêmica — resolvi responder nesse post dez perguntas para uma astroquímica na Holanda:

1. Qual sua cidade natal?
Eu nasci e cresci no Rio de Janeiro, Brasil. Tenho “r” e “s” puxados e muita saudade de Matte Leão. Em tempo: é bixcoito.

2. O que você está fazendo em Leiden?
Estou aqui para fazer meu doutorado. Cheguei há mais ou menos quatro meses, então ainda tenho mais três anos e oito meses pela frente!

3. Sobre o que é o seu doutorado?
É sobre a formação de moléculas orgânicas complexas em gelos interestelares. Basicamente, eu simulo ambientes espaciais no laboratório e estudo as reações químicas que acontecem na fase sólida nesses ambientes super gelados.

4. Que tipos de experimentos você anda conduzindo ultimamente?
Recentemente eu finalizei o meu primeiro projeto do doutorado. Fiz uma série de experimentos para investigar as rotas de formação de metanol no espaço! Quando o artigo for aceito eu conto mais detalhes. 😉

5. Como tem sido essa experiência do doutorado?
Tem sido super estimulante. Eu sou completamente apaixonada por ciência e pelo meu tópico de estudo, então todo dia é como uma aventura para mim. Desde criança eu sempre quis ser cientista. É muito louco poder dizer que estou vivendo meu sonho de infância.

6. O que você mais gosta sobre sua área de pesquisa?
Eu gosto de pensar sobre como um ambiente tão vazio e hostil como o meio interestelar/circumstellar pode dar origem a essencialmente todo o inventário molecular que temos na Terra. E eu gosto de poder explorar essa química exótica em laboratório, colocando a mão da massa mesmo.

7. E o que você gosta sobre Leiden?
Eu gosto da atmosfera da cidade. É muito diferente do Rio e de São Paulo, onde eu morei antes. Aqui é bem mais tranquilo e com bem menos gente. Ainda assim, tem muita coisa pra fazer de lazer.

8. Algo inesperado sobre a vida na Holanda?
Uma coisa que já tinham me contado antes, mas que mesmo assim me surpreendeu foi que todo mundo aqui fala inglês. Realmente todo mundo! Eu comecei a aprender Holandês porque estudar línguas é um hobbie meu, mas é tranquilamente possível viver aqui só falando inglês.

9. O que mais você gosta de fazer em Leiden além da pesquisa?
Eu gosto bastante de visitar os museus que têm aqui por perto e de ir ao cinema. Semana passada estava tendo um festival de cinema na cidade e eu e meu namorado assistimos uns dez filmes! Temos até cartões fidelidade dos museus e cinemas.

Oct

2021

Back to in-person conferences 101

If you told the home-quarantined vitamin-D-deprived Julia of 6 months ago that in less than a year she would not only have finally been able to move abroad for her PhD, but also to attend in-person conferences again, she would have rolled her eyes obnoxiously. Nonetheless, here we are: in a plane heading back to the Netherlands after spending a week in the Elysian island of Capri for the 2020 European Conference on Laboratory Astrophysics. And it doesn’t end here! Just over two weeks ago there was the first annual InterCat retreat at the blissfully bucolic Sandbjerg Gods in Sønderborg, Denmark. But as we begin to finally grasp some resemblance of what the academic life used to be before the pandemic, so starts the ever-lasting human struggle to adapt to any new circumstances. After an intense period of extended scientific and social stimuli, there are a couple of thoughts I’d like to share about how to deal with the “new normal” of academic rendezvous—or rather, how to actually be able to enjoy them as they come.

Don’t be afraid to ask questions

Clicking on a button that says “raise hand” while sitting in your room wearing the quintessential virtual-conference attire of a nice top combined with the designated pair of joggers of the week is definitely not the same thing as actually putting a hand up after a talk in a room filled with more experienced and established colleagues. And while that has always been a struggle even before Covid, the transition from the former scenario to the latter can sometimes be fairly turbulent. So remember that you have as much right to be present in the conference as anyone else, and that your thoughts matter. Believe me, after you break the spell and ask a question for the first time, the next ones will get easier and easier.

Enjoy your venue!

Although this tip is definitely more of a no-brainer, it may serve as an important reminder to some busy bees out there. Cherish this opportunity uniquely offered by in-person meetings and get to know new places. After the conference at Capri, I took the weekend to visit the archeological ruins of Pompeii, one of the most enriching and memorable places I’ve ever seen. Even if you don’t have the weekend off, just exploring the surroundings of your hotel for an hour or two can already help assuage some of the pronounced wanderlust I’m sure most of you have been feeling for the past year and a half.

Talking about science is a great way to network, but doing otherwise can also be

One of the main challenges of on-line meetings is to provide the interchange of ideas and networking that play an important part in any conference. In person, we have the opportunity again to chat during coffee breaks and meals, and properly get to know each other. Even so, those conversations can sometimes become a daunting task, especially for my fellow introverts out there. If discussing a particular scientific topic is too outside your comfort zone, don’t be afraid to approach people by talking about something else.

The pandemic will be over – if you want it

The incredibly fast development of the vaccines for Covid-19 has completely changed the course of the disease worldwide. Now, many highly-vaccinated countries have been able to ease social-distancing guidelines and allow in-person meetings again. However, the pandemic is still ongoing, and we cannot afford to act as if otherwise. Simple measures such as properly wearing a face-mask when in crowded spaces and getting tested after the trip can save a life. Read that again.

Aug

2021

Summertime plans!

In his novel “The Picture of Dorian Gray”, Oscar Wilde encapsulated the burgeoning cynical movement of the late Victorian Era in the blatantly hedonistic character of Lord Henry. Throughout the entire book, we are faced with many of his dire ideas disguised as alleged ugly truths. However, since moving to Europe, I’ve found one sentence in particular to be surprisingly accurate. Days in the summer, indeed, are apt to linger—although I mean that in a much more literal sense than the character originally did. For someone who has only ever lived in tropical cities, the Dutch sunsets at 10:30 in the evening come with a very whimsical feeling of prolonged leisure. So, to reply to Alfie’s question in his last post, for the rest of the summer I plan on seizing the long canicular days and their serotonin-inducing capabilities.

This summer is also a very good opportunity for me to properly learn how to ride a bicycle, which I have been intentionally avoiding since my childhood. I have recently acquired a second-hand bike that will be my faithful squire on my commuting endeavors to the lab, and I plan on mastering its ways before summer ends. Or, at least, to be able to cycle straight while signaling a turn. Given the notorious cycling statistics of the Netherlands, I still have a long way to go before I can feel on the same level as the regular Dutch cyclist—but I have four years to practice, after all. Alfie, is it common to ride bikes to work in Denmark too?

Jul

2021

First weeks as a doctoral candidate

Since my last blog post, I’ve been dedicating my time to learn all the ins and outs of SURFRESIDE3. As I jokingly said to my daily supervisor at the end of the first week in the lab, “I feel like my brain is now twice the size it was five days ago”—and I mean that in the most positive, Seuss-esque possible way. I have also been seizing opportunities to explore the different facilities at the University, which are filled with historical value.

The laboratory astrochemistry field is dedicated to studying the chemistry of space by recreating its conditions in the lab. This usually involves achieving very low pressures (around 10^-9mbar or 10¹² times below atmospheric pressure), and temperatures. Interstellar dark clouds are typically at around 10 K, or approximately -260 °C, so low that we need cryogenic techniques to reach them. At SURFRESIDE3, we achieve that with a closed-cycle Helium cryocooler, which only rarely requires refilling with He gas. However, some experiments involve additional apparatus that also need to be routinely cooled down.

Coincidently this week, we ran out of liquid N₂in the lab, which resulted in the coolest (pun absolutely intended) visit to the Cryogenics Department at Leiden to refill our tank. On the way there, we made a stop at the display of the first system that succeeded in liquefying He, developed by Dr. Heike Onnes in his lab at Leiden University in the beginning of the 20^thcentury. I wonder if Alfie has visited some interesting facilities too!

Replica of the apparatus Onnes used to liquify Helium for the first time. It yielded a sardonic final amount of about one tea cup of liquid He.

It feels good to be back in a lab, conducting experiments and exploring the idiosyncratic ways chemistry works at such extreme conditions as one finds in interstellar clouds.

Jul

2021

How to prepare a move to another continent in less than one week— pandemic edition

A conspicuous part of being an early stage academic is the itinerant lifestyle often associated with it. Besides its fun and adventurous aspects, moving countries is also invariably a demanding task. For perfectionistic overthinkers like myself, the mere act of preparing the luggage can spiral into an excruciatingly elaborate reverie of highly improbable scenarios that make you second-guess your every choice of clothing. If you add a global pandemic on top of that, things can get particularly gruelling. Of course, those small hurdles are quickly forgotten the minute you finish settling into your new home. Nonetheless, the stress-inducing capabilities of a moving ordeal amidst a global health crisis should not be underestimated. If you find yourself having to go through something similar, fear not! I happen to have successfully (although not-so-seamlessly) experienced this same process, and am now on the other side. Since experience is the best teacher, I though it would be useful to list a couple of tips that I’ve learned while trying to organize my move in about one week.

1 – Diligently check the COVID-19 regulations to enter your destiny country.

Each country has developed its own set of regulations to prevent the spread of the coronavirus. Many places now require negative tests and/or mandatory quarantine periods upon arrival, even if you’re fully vaccinated. So, it is very important to keep yourself up to date with the travel requirements of your destiny country, and make sure to cover all necessary arrangements prior to your self-isolation period. Also check if the immigration requires any specific form or declaration, and make sure to bring extra copies.

2 – Make a painstakingly detailed list of everything you plan to take with you.

Arranging the luggage in this kind of situation can be fairly overwhelming, especially if you are required to self-isolate for a handful of days after you arrive. To ease the fear of forgetting that one plug adapter into which your laptop’s power cord fits, or that particularly comfortable pair of socks that are currently in the laundry basket, I advise you to do what every organisation-enthusiast like myself love to do: make lists. But take it to the next level. You should list every single thing you want to take with you, in as much detail as you can. Although it can feel like you’re being too precious at first, trust me: this will make the actual arranging of the luggage much more straightforward.

3 – Look for bureaus de change outside the airport

Admittedly, exchange offices at airports are fairly convenient: they are usually open 24h and can be easily found nearby international boarding gates. However, these amenities do not come without a (literal) cost. More often than not, the exchange fees in airport bureaus de change are heavily overpriced. If you don’t mind the extra trip, it may be worthwhile to look for alternative locations.

4 – Ask other compatriot expats what they think is essential to bring

Cultural differences are expected, and even desired, when moving to another country. It is part of the expat experience and makes the everyday life more exciting. However, sometimes there is no need to deprive yourself of that specific item that you grew accustomed to and that you can’t easily access in your new home. Before leaving Brazil, I asked people on Twitter what they wish they brought with them overseas and was very surprised with the volume of responses I got. Apparently, our much-appreciated “Havaianas” flip flops can be something of a luxury item abroad, based on the over 50 replies I received adamantly advising me to bring an extra pair.

May

2021

Day in the life of an incoming PhD candidate at home (with tips!)

Recently I’ve come across an old trend in YouTube called “day in the life”, which basically consists of people filming their entire day and sharing it online. Despite my initial skepticism of its appeal, I was successfully allured by the website’s algorithm and, before I noticed it, I had spent an imprudent amount of time watching those types of videos. Honestly, it was very interesting to see what the everyday looks like for different people from all parts of the world. Specially during these pandemic times, it seems worth it to document the secluded routines that we’ve somewhat gotten accustomed to. For these reasons, I decided to write a blog post about the Day in the Life of an incoming PhD candidate during self-isolation. I also included some tips that I try to incorporate into my routine to make it more stimulating.

I was born and raised in Rio de Janeiro, a city brimful of natural wonders such as the ravishing beaches it is so famous for. Consequently, I’ve grown accustomed to a certain level of naturally flamboyant landscapes without even noticing it. Two years ago, I moved to the metropolitan city of São Paulo to pursue my master’s degree, and found myself surprisingly longing the beautiful scenery I inadvertently took for granted. Now that I’ve finished my master’s and that most activities have gone online, I have been privileged enough to be again by the sea—and I’m making sure to cherish it. So my morning routine basically consists of a walk through the beach—sometimes longer, sometimes shorter, depending on the day. There’s something nice about feeling the sand beneath your feet that can really set the mood for the day. But I digress.

After my walk, it’s time to start the activities of the day. Normally I like to begin by reading some papers related to my research—either relevant reviews or a couple o recent publications. Something to make the brain start ticking. It also serves as a much-appreciated daily motivation boost. So, tip #1 is: do something each day to keep yourself motivated.

Shortly after that it’s usually time for some meetings. Since I’m living on a timezone 5 hours earlier than my institution, most of my meetings take place during the morning. As an archetypal early bird, I am perfectly comfortable with this schedule—but I can see how this could be a nuisance to some people. This leads us to tip #2: try to adjust your schedule to your own circadian rhythm.

After lunch break, I usually go through an afternoon slump, and so I like to do more engaging activities to try and compensate for it. Today, that meant spending a couple of hours working on some publications that are close to submission. Then, when I was done with the papers, I started preparing a presentation I am supposed to give to my colleagues in our next group meeting. I find that listening to classical music playlists while writing or preparing slides always adds a fun component to my work, so tip #3 is: remember to keep it fun.

In the evening I like to wind it down by doing some quick research on fundamental principles related to my project. The topic of today was the Temperature-Programmed-Desorption technique and its applications. If you have no clue what that is, Rijutha and Andrew made a very informative video on this technique, which you can watch here. So, tip #4 is: it is always worth going back to the basics.

Finally, it’s time to rest. For me that means watching TV shows or reading fiction books. Currently I’m finishing Oscar Wilde’s great masterpiece The Picture of Dorian Gray, and I’m truly loving it. I don’t know why it took me this long to finally read it, but I’m glad I did. The final—but not less important—tip is: don’t forget to take the time to do other things you enjoy.

May

2021

Starting a PhD from overseas: an introduction

The first piece of advice you will receive when planning to apply for a graduate degree is to never start your essays with cliché childhood reminiscences about your love for science and academia—however truthful they might be. Thankfully, I have already been accepted into a PhD program, and so I reserve the right to this little indulgence: since I can remember, natural sciences have always been my passion, and research has always been my purpose. Over the years, this very precocious—and, honestly, a little unsettling—certitude about what I wanted my whole career to be resulted in an accumulation of long hours imagining what my life would look like at each step of this journey. However, not even in my most dystopian Orwellian reveries could I have imagined that my PhD would start during the worst global-health crisis of the last century, and that I would just have to deal with it.

I applied for and was offered a position to work as a PhD candidate at Leiden University, as a member of the Laboratory for Astrophysics and as a part of Intercat. For my doctorate, I will be exploring the formation of complex organic molecules in space through laboratory experiments on interstellar ice analogues. Consequently, most of my time during the next four years will be spent either thinking about or conducting experiments on SURFRESIDE³, a really sophisticated setup that requires specialised training and, naturally, in-person handling of the machinery. Still in Brazil, I find myself unable to travel to the Netherlands due to the pandemic situation, and therefore I am faced with the challenge of trying to become acquainted with the setup without being able to actually handle it.

“Augean task” would be an understatement. There are no guidelines as to how to start any PhD from over 9000 km away, let alone a lab-oriented one. Besides an extensive reading list comprising most—if not every—work previously done with SURFRESIDE³, there is not really an obvious way to take profit of this restless waiting stage. We have to be creative. Last week, my daily supervisor took me on a virtual tour of the setup, using his laptop camera to guide me through the experiments he was conducting. It was surprisingly fruitful to be “present” while the first Reflection-Absorption Infrared spectra were obtained from the ice, which fuelled me with excitement for the rest of the week. After the meeting, I felt reassured that I was on the right track.

This pandemic is a burden that will forever remain in the memories of those who survive it. Being situated in one of the worst hotspots of Coronavirus in the world, and under the authority of less-than-ideal political figures that refuse to acknowledge reality, languish and apathy regrettably beckon. Still, small pleasurable moments such as my virtual rendezvous with SURFRESIDE³ are the breath of fresh air that can encourage us to keep looking forward. As Leo Tolstoy once said, life does not stop, and we indeed need to live. So we keep on living, and doing our best to navigate this pandemic while trying to get to the other side of the Atlantic—occasionally writing blog posts in the meantime.

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