Testimonials

Programme

Mathematics

Sterre van Dijk is a first-year Mathematics student at Radboud University, and it turns out that it suits her perfectly. "You learn to think in a different way," she says. However, she almost didn’t choose mathematics.

Sterre was very good at Mathematics A in high school, but Mathematics B was hard. Her friends suggested studying Mathematics, but she was more inclined to choose Dutch language and culture.

Why was that?

 “For Mathematics A, I had incredibly good grades in my fourth year. My teacher did not say anything, however. It’s very simple: you can only choose Mathematics B if you have a 7,5 or higher, and I had a 7. So, I thought I’d study Dutch language and culture after school. That also seemed interesting. However, before my final exams, I had a great conversation with my mathematics teacher, who said, "Why not take a gap year and get a certificate for Mathematics B? After that you gain access to studying Mathematics. If anyone is good at math, it's you.’”

What did you do then? 

“I followed her advice and I’m still grateful for it. I obtained the Mathematics B certificate. During the gap year, I also worked at a homework tutoring institute. There, I saw how little attention was paid to students' capabilities. They mainly looked at grades, not at talents. I often interfered in those cases.”

Do students need such involvement, do you think? 

“Yes, because what mathematics teachers often say in high school is not enough. You can’t make a truly informed choice with that. As a first-year student, I’m also involved in domain guidance. We visit schools to explain what the mathematics programme involves. We can also share our own experiences. My advice to anyone considering this is: attend open days and try a trial study day. That way, you’ll really feel what it’s like and get an idea if it’s right for you.”

What is special about mathematics that attracts you so much? 

“You learn real problem-solving skills. You also learn to ask questions to analyse problems. Mathematics—especially the theoretical side—is very practical. The strange thing is, if they asked me a physics question about a cart on a slope, I’d often lose interest. But if you ask me something about vector spaces, you have my full attention. I understand how simple it actually is, and I can completely immerse myself in it. You really need time and perseverance for mathematics. I work every day from nine to five, because if I don’t, I fall behind.”

What will you do with mathematics in the future? 

“I once took a competency test at school, and it showed that I could be a good teacher. At that time, I didn’t see it at all. But now, after just a few months at university, I think it could be a good fit. I’m not sure if it will be at a high school or at a university of applied sciences, but teaching is something I could see myself doing.”

What challenges would you like to face?

“There are still countless fields in mathematics that are not yet explored. Professors are scratching their heads over them, such as algorithms. I would really like to dive into that and find a solution. You have to be brave to ask the right questions, and I’m definitely brave enough.”

Previous education

Mathematics

Programme

Mathematics

Stefanie Sonner was named the best young teacher of 2021 by the students and faculty of the Faculty of Science and the best mathematics teacher of 2021 by the mathematics students. The rotating trophy, in the form of a plaque with an inscription, stands in her office. "I see these awards as recognition of my educational efforts," she says with a modest smile.

Stefanie Sonner received her PhD in applied mathematics, focusing on the analysis of differential equations and their applications in biology, from Munich. She then worked as a lecturer and researcher in Bilbao, Kaiserslautern, and Graz. "I have now been associated with Radboud University for over four years."

As a lecturer, Stefanie Sonner gives lectures to both bachelor’s and master’s students in mathematics. She also supervises students in writing their theses. Additionally, she is a member of the Mathematics Program Committee, where she works on restructuring and streamlining the master’s program in mathematics. "Formally, 40 percent of my workweek is dedicated to teaching, 40 percent to research, and the remaining 20 percent to administrative tasks."

Multilingual Proficiency

Thanks to her academic career in various countries, Stefanie Sonner is proficient in multiple languages. In addition to her native German, she speaks Spanish, Portuguese, English, and Dutch at a high level. "I speak and write English at a professional level; it’s the language of science. My Dutch is quite good, although I sometimes struggle to find the right word."

The talent and mental flexibility that Stefanie Sonner has in language skills are also evident in her research work. "I conduct research in theoretical mathematics, but also in mathematical biology. In this field, I analyze models for biofilms and cell communication."

Biofilms, such as Dental Plaque

"Biofilms are groups of microorganisms that form a biological system, such as dental plaque. The growth of biofilms can be described by a mathematical model," explains Stefanie Sonner. "I analyze that model; does it show the correct behavior and does it explain what we see in experiments? It’s like solving a puzzle. Just working with a blackboard and chalk or pen and paper, thinking logically. It can take weeks, months, or even years; you never know in advance."

"Mathematicians are often inspired by a concrete application, but we aim to develop mathematical theories that are as general as possible and applicable to a wide range of problems."

Cell Communication

Stefanie Sonner collaborates with the Department of Cell Biology at Radboudumc on mathematical models for cell communication. "In such a system, many processes occur, and there are unmeasurable background processes. With a mathematical model, I try to map out what happens in the background. We use simulations to see if the model matches experimental observations. If it doesn’t, I have to adjust the model assumptions. This is an ongoing process in science."

Targeted Medication

"Practically, research into biofilms and cell biology aims to map out the key processes occurring in a cell or system. Only then you can direct the cell or system to desired behavior, or in medical terms, treat disease with targeted medication."

Previous education

PhD in Mathematics, University of Klagenfurt (Oostenrijk) en MSc in Applied Mathematics, University of Belgrade (Servië)

Programme

Mathematics

Country of previous education

Duitsland

Vanja is a lecturer in Applied Mathematics at Radboud University. She investigates the use of mathematical models to understand ultrasonic waves. 'Mathematics is like solving a puzzle.'

After completing her PhD in Austria and postdoctoral research in Munich, Vanja Nikolić joined Radboud University in Nijmegen in 2019. She is on a path to becoming an associate professor and teaches both undergraduate and postgraduate students. Her current research focuses on using mathematical models to understand ultrasonic waves. 'These waves, for example, assist doctors in viewing the body during prenatal ultrasounds. They can also be used for treating tumors, avoiding the need for surgery.'

Working with mathematical models 

Vanja works with mathematical models that describe various phenomena. 'I specialise in models that capture non-linear ultrasonic waves. Many colleagues primarily conduct research in laboratories in this field. We document what we observe in the lab on a computer. This enables us to explore basic principles in a simulation environment, which is also cost-effective.'

Non-linear waves 

Sound travels as a wave, similar to water waves. 'The sound you hear when I speak is almost identical to the sound I produce. This is an example of linear sound behaviour. However, non-linear waves can change shape as they propagate,' explains Vanja. 'Such interesting phenomena occur naturally in ultrasonic waves. They have very high frequencies, making them inaudible. These waves are utilised in various medical applications, both diagnostically and therapeutically. The most well-known example is creating images of the body, such as in prenatal care.'

Research into medical applications 

One of the intended applications of ultrasonic waves is cancer research, potentially eliminating the need for mammograms. Scientists from different disciplines are working on this. Another research area is their use in tumor therapy. 'Therapeutically, we can use ultrasonic waves to destroy tumors. Focused ultrasound can generate high pressure and heat tissue, reducing or destroying cancer cells,' Vanja explains. 'The advantage is that it is painless, non-invasive, and can be repeated frequently.'

Constantly generating new questions 

'My research constantly generates new questions about the underlying ultrasound models, especially in the context of the mentioned applications. There are always potential improvements to discover, which is one of the reasons we do this work. There are always questions to ask and answer.'

Solving mathematical puzzles 

'When I started, there were many mathematical challenges in our field. Some of those theoretical questions have been answered. I am proud of that,' says Vanja. 'An important milestone was that we can now capture how non-linear ultrasonic waves depend on the properties of the medium they travel through. We could demonstrate a certain continuity when waves travel through different media. In mathematics, answering open questions is always fascinating. It's like solving a puzzle. The reason we do this theoretical research is to create a comprehensive understanding of ultrasound. We want to generate a complete picture that will also assist other researchers and laboratories in the long term. We aim to establish something that contributes to a deeper understanding of the field.'

Increasing efficiency 

Obtaining a fundamental understanding of the underlying mathematical models is very important. Vanja: 'It contributes to more efficient use, enabling us to make computer simulations more reliable and efficient. It brings them closer to the real world.'

Inspiring and motivating students 

'Another beautiful aspect of my work is interacting with students and sparking their interest in mathematics. Engaging with students who conduct research and develop a passion for the subject is a wonderful part of my job.' Vanja concludes: 'And sometimes students come up with ideas that I hadn't thought of myself. I find that amazing!'

This interview was previously published on TechGelderland.nl.