As any other very curious kid, I had a deep interest for science when I was young. However, when it came the time to really choose a professional career (15-17 years old, in 2003-2005), I had a hard time choosing what I would like to do for a living. I guess this is because I always had a genuine appreciation for all fields. I thought about becoming a musician, a mechatronics engineer, an agronomic engineer, a biologist, a chemist, and even a web designer. But none of these options hit the bull's eye. In 2005, when I was 17 years old (about to choose an undergraduate course and university to pursue), the field of stem cells, genetics (remember the Dolly sheep?), and nanotechnology (robotics and miniaturization) were absolutely present in all the news. Somehow, we were all convinced that the solution to most of human beings' problems would be, in principle,  solved by scientists that would work in those fields in the near future. Obviously, I wanted to somehow study directly all of that. But how? At that time, multidisciplinary careers basically did not exist.

 Luckily, a piece of a very eye-catching news article in the Brazilian newspaper Folha de São Paulo carried the following headline on August 30, 2005, "New bachelor's course at USP intends to form 'super-scientist'". The article referred to the recently approved Bachelor's program in Physical and Biomolecular Sciences, which would be inaugurated the following year at the São Carlos Institute of Physics (IFSC/USP). "The post-graduation in Biomolecular Physics already existed in the Institute and, for this reason, when the undergraduate course in the same modality was inaugurated, we already had a well-prepared faculty", recalls Ana Paula Ulian Araújo, former course coordinator. 

My high school administration printed and hung the newspaper article on the school walls. My physics teacher, absolutely enthusiastic about it, came to his class and shared the news. Why even he was enthusiastic about it? Maybe that was because the idea of such a Bachelor's course was definitely novel and very ambitious for an undergraduate program in one of the most competitive Brazilian Universities - the University of São Paulo (USP). The syllabus of the course was intrinsically multi-and-interdisciplinary, mixing fields such as Physics, Mathematics, Biology, Chemistry, and Computer science. The Bachelor's course coordinator, Prof. Dr. Otávio H. Thiemann, who was interviewed in the article, explicitly said: "Those who choose physical and biomolecular sciences are going to have a solid foundation in physics, in chemistry, in mathematics, and in molecular biology," And added: "But we will also show an entrepreneurial aspect to the course." According to the professor, in general, researchers are trained to develop studies and publish them. "Thinking about products is not trivial. And it is possible to create patents and microenterprises. We will give the first taste of how to do this," he said.

To pass the entrance exam (vestibular) and to begin this novel and ambitious undergraduate course in 2006 would not be easy. In order to study at USP, one would have to pass the most competitive national public exam (FUVEST), which is very challenging. I knew it, and, in fact, everybody in Brazil knows it. Most of the students don't pass the first trial to enter at USP at any given undergraduate course. The University of São Paulo has oftentimes been considered the best university in Latin America (QS World University Rankings) for many years in a roll, and guess what? It is 100% public/free. By that, I mean that students don't pay any extra cents to study - there are no annual administration charges like other public universities in Europe and the USA. Super attractive, no? So, after a few trials, I passed the exam, and I was accepted to start the 3rd class (2008) of "Biomol". I was quite convinced that such a bachelor's program would be the best fit for me. And that is how my academic career started.

• [2008-2012]: The Bachelor's program in Physical and Biomolecular Sciences (IFSC/USP)

In 2008 I began the Physical and Biomolecular Sciences Bachelor’s program at the Instituto de Física de São Carlos (IFSC/USP). This is a full-time, very challenging, and interdisciplinary program. The Biomolecular Sciences students take exactly the same classes and exams as other physics, engineering, chemistry, and mathematics undergraduate students. At the USP campus in São Carlos city, we were basically one of the first students to have genetics and molecular biology-related courses at the undergraduate level... maybe we were even one of the first in the country to take these courses in a Bachelor's program. Typical topics on advanced biomolecular courses were only given at the MSc or PhD degree level in general.  Anyway, during my first year at the USP, I realized that it would be crucial to start planning my academic career in the long term - to be prepared for a Ph.D degree. To make a long story short, the whole Bachelor's program aims at developing a strong background in physics first in order to apply this knowledge to investigate biological systems in a more quantitative way later. Most of the "Biomol" students choose the path of X-ray crystallography, NMR, or EPR spectroscopy, and they use these approaches together with some biochemistry tools to probe biomolecular structure and function. But, I got fascinated by visible optics and microscopy.  Thus, I decided to develop a strong and broad background in advanced optics first, to subsequently use this knowledge to investigate biomolecular and cellular systems later. Just to mention, we all took courses like: Quantum Mechanics, Electromagnetism, Statistical Physics, Methods on Mathematical Physics, Optical Physics, Biochemistry I & II, Medicinal Chemistry, Enzyme Technology, Protein Engineering and Modeling, Molecular and Cellular Biology I & II, Microbiology, Structural Molecular Biology, Computational Molecular Biology, Introduction to Computing, Introduction to Electronics, among others...  Besides, most of the "Biomol" students (including myself) managed the little available extra time to perform many extracurricular activities, including part-time undergraduate research, as explained in the following paragraphs.

• Undergraduate extracurricular activities: undergraduate research, international internship, awards, leadership experiences, and organization of academic and social events 

It is worth highlighting some parallel activities I took during this full-time Bachelor’s program. I was chosen by my colleagues to be the student representative in the IFSC’s General Council in 2010. In the same year and also in 2011, I was a member of two organizing committees for IFSC’s academic events (workshops involving both undergraduate and graduate research students: the SEMAFIS and the SIFSC I). In 2012, I was awarded a research studentship by USP to carry out a 2-month international internship at the Center for Nanoscience and Technology (CNST/IIT at the Politecnico di Milano, in Italy), under the supervision of Prof. Dr. Guglielmo Lanzani and Dr. Sai Santosh Kumar Raavi (current professor at the University of Hyderabad, India), in order to get experience with Time-Resolved Ultrafast Spectroscopy. Although it was a very short internship with limited funding, it was such a fantastic experience for me for many reasons: it was my first professional experience abroad, and I had to deal with a different language. I learned a lot of English vocabulary, but also a bit of Italian. Obviously, I began my professional networking at the international level there. In Milan, I met many people, including one of my current close friends, Dr. Sameer Guduru, who at that time was doing his PhD there. Curiously, four years later (2016), I reencountered him in Marseille (France), when I was doing my PhD, and he was doing his postdoc. Besides,  at the Politecnico di Milano (Italy), I made my first talk to an English-speaking audience (group meeting) and Dr. Santosh taught me a few concepts and optical instrumentation tricks during that time. 

Besides, from 2008 to 2013, I attended many academic events (above 20),  completed a full English course, developed my part-time undergraduate research in ultrafast spectroscopy of ultrathin films of semiconducting polymers (see below), and finally graduated in Biomolecular Physics.

1st research project:  probing femtosecond energy transfer on polymeric nanofilm photosynthetic models with controlled bandgap structures.

In Brazil, undergraduate research is called Iniciação Cientítica (IC) (literally translates to "scientific initiation"), and it is a part-time internship you choose to do in a given lab (optional extracurricular activity). Sometimes the Principal Investigator (PI) of a given lab has already the IC scholarship to afford, or sometimes the student comes to a PI and then they apply for funding together. Sometimes the student carries out the IC without any funding. At that time, I was highly interested in optics and nanotechnology. One day, a close friend of mine pointed to me a new IC advertisement hanging on the computation room wall. It was about a PI looking for an IC candidate to apply together for IC research funding in ultrafast optics applied to organic nanofilms. Perfect. The PI was Prof. Dr. Paulo B. Miranda, and he wanted an intern to help his PhD student build up an ultrafast time-resolved experiment. Then, I came to his office at "Prof. Bernhard Gross Polymer's group" at IFSC/USP, and we applied for (and got) the most competitive Brazilian scholarships for undergraduate research (FAPESP and CNPq). For more details, check the Research link.

 It is worth highlighting that my undergraduate work received 2 awards in scientific events: a national one (20th SIICUSP. given by USP) and an international prize (the best poster presentation at II USP Conference on Nanotechnology in 2012, given by The American Chemical Society, ACS). Furthermore, my undergraduate work was selected for oral presentation at the International Congress ICMAT 2013 in Singapore (presented by my supervisor). 

• [2013-2015]: Master's research on nonlinear optical spectroscopy applied to biomimetic membranes (IFSC/USP)

2nd research project:  unraveling the antimicrobial molecular mechanism of action of chitosan biopolymer on biomimetic membrane models.

After my Bachelor's graduation in 2012, I spent around 3 months studying possible topics for my Master's research. At that time, I was interested in nonlinear optics, because this field was fundamental to many powerful techniques that people could use to investigate biological systems, including myself in the future. In particular, most of the IFSC/USP researchers working with optics were somehow working with nonlinear optics, including Prof. Paulo B. Miranda. Besides, I had already in mind the research path I would like to follow: somehow I would like to use optical experiments to investigate more realistic and complex biological systems in the long term. So, the discussion and planning of my Master's project with Prof. Paulo B. Miranda took that into account - to be an intermediate step between an abstract concept model (organic nanofilms) of photosyntetic system to systematic investigation of a real cell or tissue structure/function (possibly, in the near future PhD).  Then, I wrote down my own Master's research project, and I presented a complete Master's research project to him. After a few important meetings, we made the right corrections, and we successfully got a Master's research funding (CNPq and later FAPESP). My Master’s research project aimed at understanding the molecular mechanism of action of polymeric antimicrobials (Chitosan and PAH) on cell membrane models (biomimetic Langmuir Monolayers) using SFG Spectroscopy – a surface-specific nonlinear vibrational spectroscopy.  In particular, Chitosan is a well-known antimicrobial biopolymer, with many attractive properties and applications.  Chitosan is a polymeric material with rich literature. The scientific community has already synthesized and used chitosan and its derivatives in many different antimicrobial applications (clothing, coatings, solutions, etc). In addition, one may even find in the literature that chitosan could be used in a promising combination with other antimicrobial molecules or even photosensitizers as a drug-delivery agent, yielding a synergistic effect against pathogens. Nonetheless, its molecular mechanism of interaction perturbing biological membranes remained elusive at the molecular level. Interestingly, chitosan and its derivatives are effective against bacteria, fungi, and even viruses, but do not cause any harm to human cells.  Thus, it is biocompatible with human cells. More information about this work can be seen in the Research section of this website. Besides, during the same period, a collaborative paper about semifluorinated thiols organization in Langmuir monolayers, held mainly by the postdoc fellow Dr. Diogo Volpati has been published during my Master's research experience.  

• The interest in fluorescence-based techniques: fluorescence super-resolution microscopy and single-molecule approaches

My interest for fluorescence approaches such as super-resolution microscopy began in 2013, after those meetings with Prof. Miranda about my Master's project. At a given moment, I naively asked my supervisor if he knew someone outside Brazil who has been working with state-of-the-art optics applied to "real" biological systems (as opposed to biomolecular models). Then, he presented me with a paper about STORM super-resolution microscopy from his Berkeley doctorate colleague, Prof. Dr. Xiaowei Zhuang, that has been working at Harvard University in the USA. After that, I began reading articles about super-resolution and related single-molecule topics, and I realized that fluorescence approaches can be incredibly powerful - even more than I was awared of. Thus, during my Master's study, I began to search for Ph.D. Programs in the field of fluorescence super-resolution microscopy and single-molecule techniques that investigate biomolecular structure and interactions at the nanoscale. 

• PhD applications worldwide and temporary work after obtaining my Master's degree in Biomolecular Physics

On the 4th of August of 2015, I defended my dissertation and obtained my Master's degree in Applied Physics: Biomolecular Physics. After that, I applied for a  Ph.D. program in a few places outside Brazil, and also for the grant "Science Without Borders (SWB)", a Brazilian funding program for academic internationalization.  Meanwhile I was waiting for the SWB outcome,  I got a short-term (3-month) scholarship from FAFQ (Fundação de Apoio à Física e à Química), a municipal-level scientific funding (from São Carlos city, in SP) to perform a university-enterprise (USP - FIT electronics) collaborative research about ink-jet printing of organic electronics materials and devices (nanotechnology field). At a given week, I was awarded the Science Without Borders grant, and because of that, a few universities (some were Top 5 in the QS world university rankings) were actually conditionally accepting me to start my PhD abroad (i.e., if I had my own grant). Unfortunately, on the same week that I got the grant, the Brazilian Government cut a significant amount of the science budget, including for the SWB program. I and many others lost the grant. Very luckily, due to the intense networking before getting the SWB grant, I got in touch with many different people in other fantastic equally competitive labs, including some that were working in France. There, they were needing someone like me, with a multidisciplinary profile, and they had their own funding: the CNRS (The French National Centre for Scientific Research).

• [2016-2020]: Ph.D. research experience - Polarized fluorescence super-resolution microscopy (Institut Fresnel, Marseille, France).

I got a video interview with Dr. Sophie Brasselet and Dr. Manos Mavrakis from the Institut Fresnel at the Aix-Marseille University (IF-AMU, Marseille, France), where they detailed the idea of the Ph.D. project. I got amazed. The project title was “Structural organization of cytoskeletal filaments probed by polarized super-resolution microscopy”. The basic idea was that I had to build up a polarization-resolved optical microscope with quantitative super-resolution capabilities and use that to study the actin filament structural organization of cancer cells.  It was clearly an ambitious project because I would be actively doing the sample preparation to tackle biological questions in parallel to assembling and optimizing the novel optical setup according to the needs of the biological questions we were trying to address. In the end, I got accepted and I came to Institut Fresnel. 

Fig 14 - Part of the experimental setup for 2 polarization resolved fluorescence microscopy experiments: polar-spinning disk (ensemble measurements) and 4polar-STORM (single-molecule measurements.

3rd research project:  structural organization of cytoskeletal filaments probed by polarimetric super-resolution microscopy

I started my Ph.D. by duplicating the current state-of-the-art polarized fluorescence microscopy setup (a polar-spinning disk setup) that was built on another campus in Marseille by a former PhD student in the lab, Dr. Xiao WANG. Technically speaking, this setup was a fast angle-resolved linear dichroism setup (ARLD), in which one could rotate the linear polarization of the excitation beam with an Electro-Optical Modulator (Pockels cell), and use a spinning-disk unit (multiplexed confocal scheme) to excite and collect light from the sample. The idea was to build up this ensemble setup close to the novel setup I would build up during the PhD (a polarized single-molecule and super-resolution microscopy setup). To work with both side-by-side during the PhD would be very important to make comparisons. We could optimize the experimental conditions and perform investigations on actin filament organization from ensemble to single-molecule level. Thus, I built up both setups on the same microscope stage, and made countless experiments. Experiments ranged from sample preparation optimization and hypothesis-driven tests (labeling quality, cell culture conditions tests, fixation protocols, coverslip coating & patterning studies, perturbation experiments, etc) to optical performance tests and some computational quantitative imaging performance evaluations before reaching the final and conclusive experiments. The novel polarized super-resolution microscopy setup that I built up was, in simple technical terms, a STORM microscopy (Stochastic Optical Reconstruction Microscopy) in which the anisotropic polarized fluorescence emission by single-fluorophores could be projected (measured) simultaneously onto 4 analyzer channels (0°, 45°, 90°, and 135°).  We coined the technique as 4polar-STORM (Nat Commun 13, 301 (2022)). With this technique, we showed that we can get not only reach the typical 20µm optical resolution (like STORM does), but also quantitatively measure the single-molecule orientation and wobbling (angular flexibility due to stochastic thermal movements) in a robust way in 2D. Besides, we showed that we could qualitatively access the 3D orientation of single-fluorophores because the axial component of fluorophore dipoles affects the wobbling readout that we probe. Thanks to that, we could statistically quantify orientations of single-molecule and their flexibility range in subdiffraction regions of biological fixed cell samples. Therefore we were able to investigate complex supramolecular structures made by actin filaments (e.g. lamellipodial organization, stress fiber alignment, etc) under different conditions. This work opened a whole new avenue for quantitative imaging studies in cell and molecular biology. At the end of my Ph.D., I came back to Brazil just before covid-19 pandemic to write my thesis. Due to covid-19 pandemic outbreak, I defended my thesis online on the 30th of November 2020, obtaining my lifelong goal of obtaining a Ph.D. degree in Biophysics. Yay!

• [2021]: The covid-19 pandemics and the search for the first postdoc position 

After the Ph.D. defense, I went on vacation for a few months - at home, like everybody during pandemics.  Then, I contacted Prof. André A. de Thomaz, from IFGW (UNICAMP, Brazil), a young researcher specialist in the field of super-resolution fluorescence microscopy, that had previously worked with Prof. Dr. Paul Selvin (University of Illinois Urbana-Champaign, USA). Prof. André has a strong collaboration with the biology department of UNICAMP university, in particular with Prof. Aline M. Santos in the field of cardiomyopathies. Since their research topic was not that far from the one of my PhD, we decided to apply together for a postdoc grant. It took a few months to write the project, and another few months to receive the first feedback from our grant proposal. However, even before receiving a feedback from reviewers, the Brazilian Government decided to cut 87% of the whole science budget. This happened, in the middle of 2021, when the whole world had many uncertainties due COVID-19 variants. I knew that even in normal conditions getting a postdoc grant was already challenging at that time. So, after that unprecedented science budget cut, it would surely affect the outcome of most of the applicants. From this point on, I decided to not focus in staying in Brazil anymore, and began to apply to places abroad. And that's how I got my first postdoc position at Lab. Kastler Brossel (LKB), at École Normale Supérieure (ENS/PSL), Paris, France, under the supervision of Prof. Dr. Sylvain Gigan.

• [2022 - 2023]: First Postdoctoral position - Laboratoire Kastler Brossel (LKB) - Université PSL/École Normale Supérieure (ENS), Univ. Sorbonne, and Collège de France, Paris, France.

Prof. Dr. Sylvain Gigan was looking for someone to substitute his postdoctoral fellow Dr. Claudio Moretti, who moved out of academia and went back to Italy. Dr. Claudio was working in the framework of a project grant that Dr. Sylvain and other collaborators got from the Human Frontier of Science Program (HFSP). Three scientific centers from different countries got together to push the frontier of neuroscience imaging: France (Sylvain Gigan), Italy (Serena Bovetti), and Austria (Dustin Penn). The idea of the postdoc project is to develop a novel modality of microendoscopy to be applied on freely behaving mice to investigate neuronal activity during an instinctive learning process. Close to the physics lab, Dr. Cathie Ventalon, who is an expert in fiber bundle applied to freely behaving mice experiments from the neuroscience section of the Institut de Biologie d'École Normale Supérieure (IBENS/ENS), joined Sylvain as a close collaborator in the HFSP project. Both were looking for someone to resume the optical development part of the HFSP project (the French team). I was very lucky to contact them at the right time and got accepted as a postdoctoral researcher (CNRS). 

Between 2022 and 2023, I worked as a postdoc researcher at the prestigious École Normale Supérieure (ENS) at both Laboratoire Kastler Brossel (LKB/ENS , PSL , Univ. Sorbonne,  Collège de France, CNRS) and IBENS (ENS) in Paris. There, we strived to demonstrate in vitro how one could improve fiber photometry methods (deep brain microendoscopy) in demixing ensemble fluorescence activity readouts into their individual (single-source) time traces using a Non-Negative Matrix Factorization (NMF) algorithm.

• [2022 - 2023]: Living in a UNESCO Heritage Site - La Fondation Maison du Brésil - at the Cité Internationale Universitaire de Paris (CIUP). A building designed by two great architects: Lúcio Costa and Le Corbusier.

Finding a good place to live in Paris is one of the most challenging things to solve when you arrive in Paris. The rent price is incredible high for such small places and often far from the public transport sites. Luckily, my academic network recommended me to apply for a room at the Maison du Brésil at the Cité Universitaire and I got accepted. There is no doubt that this place is one of the best places for an expat student to be in Paris, due to its fairly good cost/benefit ratio in terms of price, localization,  and surrounding environment. La Fondation Maison du Brésil is a building that can hosts approximately 100 academics (students, researchers or visiting professors) for a short period, and about 80% of the room are dedicate to Brazilians. The other 20% are other academics from other countries, mainly from the other "houses" of CIUP.

During my stay in Maison du Brésil I realized that most of the students were as lost as I was during my Ph.D. in Marseille. Oftentimes a new person arrived in the building, and this person was asking the same questions about French administration. The lack of clear and reliable guidelines on how to solve administrative challenges in France made me reflect a lot on how much time is wasted with it, with so many intricated details and badly explained bureaucracy. That motivated me to create a website inspired by Wikipedia to help newcomers with reliable information on how to solve the most common administrative challenges when one arrives in France. Therefore, after discussing a lot with the temporary director of Maison du Brésil, I decided to invest my spare time in a volunteer work and I created the Wiki MdB: the online guide for Brazilian academics in France: http://www.wikimdb.fr . 

• [2024 - Now]: Achieving a tenured position: Research Engineer at the INSTITUT CURIE - INSERM - Centre de Recherche à Paris

After approximately a year and a half working in between the Physics (LKB/ENS) and Biology (IBENS/ENS) departments of the traditional École Normale Supérieure (ENS) in Paris, a beautiful in vitro proof-of-principle demonstration of a new fiber photometry method was done during such a fruitful collaborative environment. I also had the joyful experience of supervising two very smart ENS L3 students (Maurice DEBRAY and Enora BRÉMONT) for a few months during my postdoc in Paris. Hopefully, our results will be useful for the scientific community and stimulate more research in the field! Fingers crossed!

Such successful research experience allowed me to start applying for permanent job positions in France in the middle of 2023. Some of these positions were recommended by people I previously met in France. Probably, I would never get to know about them by myself. That is the importance of good communication, consistent networking, and friendships. After a few weeks of intense preparation for the 10-minute oral presentation in English and 20-minute interview in French, I passed in a public concourse of the INSERM (French National Institute of Health and Medical Research) to be a Research Engineer at the Institut Curie in Paris (yuhull!).  I'm joining Dr. Luger Johannes' team in fundamental science research on cancer disease and cell biology. (see Fig 24) 

That is a whole new beginning - a brand new cycle! Let's see what this new experience will bring!  Fingers crossed! Cheers!