Humboldt Lecture Series at Tübingen University

The Humboldt Lecture Series gives Humboldt fellows who spend some time at Tübingen University the opportunity to present their work to a broader faculty. It thereby provides a platform to discuss the research of some of the most excellent researchers from all over the world in an interdisciplinary context. Additionally, the Humboldt Lecture Series is meant to be a meeting point for all international scholars at Tübingen University.

The Humboldt Lectures are jointly organised by Welcome Center of Tübingen University, the Humboldt Club and CIIS.

The lecture series is supported by Alexander von Humboldt Stiftung/Foundation.

10 November 2021, 6:30pm

Neue Aula, Großer Senat

Dr. Melissa Jane Johnston (Neuroscience): 'Tempus Fugit: Interval Timing in Crows'

Abstract
The ability to accurately perceive time is critical for many complex cognitive abilities in both human and non-human species, including birds. While some cognitive abilities relate to time in a broad sense, such as episodic memory (when an event happened) and future planning (allocat-ing time), others, such as decision-making, require the ability to flexibly apply temporal infor-mation for goal-directed behaviour, such as temporal discounting, sunk–cost, and delayed grati-fication. For these behaviours, decision-making often depends on internally monitoring time over a period of seconds or minutes, an ability known as “interval timing”. Several bird species demonstrate sophisticated interval timing in their decision-making behaviours, however investi-gation into the neural mechanisms in such species is severely lacking. A putative candidate re-gion for interval timing in birds is the associative endbrain area termed the ‘nidopallium cau-dolaterale’ (NCL) which has been linked to high-level cognition in birds and is thought to be the avian analogue of the mammalian prefrontal cortex. The goal of the current research is to ex-plore the behavioural and neuronal representations of interval timing in the NCL in crows (Cor-vus corone), a bird renowned for its impressive cognitive skills. The overarching hypothesis of the current proposal is that the distinctly developed avian endbrain without a layered pallium adopts similar physiological solutions as mammals to common computational problems in pro-cessing time intervals.

Bio
Melissa (Millie) Johnston did her Bachelor of Science majoring in psychology at the University of Otago (Dunedin, News Zealand) from 2011–2013. Staying at Otago, she then completed her Master of Science (2014–2015) and doctorate in the Department of Psychology (2016–2019). Her postgraduate research focused on various brain regions involved in higher order cognition (e.g., working memory) in pigeons. During her doctorate, she was awarded an Elman Poole Travelling Scholarship to support her during her research visit at Ruhr Universität Bochum where she worked with jackdaws. Since completing her doctorate, Millie has worked as a postdoctoral researcher and is now a Humboldt Fellow at Eberhard Karls Universität Tübingen, where she investigates timing behaviour in crows.

Dr. Horácio Santana Vieira (Physics): 'Perturbations, Heun Functions and Quasispectrum in Black Holes Physics'

Abstract
Theoretical studies concerning the physical processes which occur in the spacetime surrounding black holes and compact objects can help us to understand the physics of these interesting objects predicted by the theory of general relativity. Among them, we should mention the investigation of the Hawking radiation, Casimir effects, the scattering of particles and waves, quasinormal modes, quasibound states, dynamics and stability, and gravitational waves sources. The investigation of all these physical processes involves finding the solution of differential equations, such as the Klein-Gordon, Dirac, Maxwell, Teukolsky, Hamilton-Jacobi, geodesic, and field equations, in the backgrounds under consideration. The exact analytical solutions for these equations are often obtained by using a class of very general functions in mathematical physics, namely, the Heun functions, which during last decades, have gained increasing importance. This can be verified by the large number of applications they have in different areas of physics and mathematics. Usually, without the use of these functions, it is not possible, in general, to find an exact analytical solution valid in the entire spacetime.

Bio
As a Master and Ph.D. Student at Federal University of Paraíba (João Pessoa/Brazil), I focused my studies on the interaction of quantum systems with gravitational fields. As a Visiting Ph.D. Student at Tufts University (Medford/USA), I worked on the quantum fluctuations of the spacetime geometry and its signature in the gravitational waves. As a Humboldt Postdoctoral Fellow at University of Tübingen (Tübingen/Germany), I devoted my research to study the resonant frequencies related to the quasibound states of different quantum fields interacting with the gravitational fields generated by a class of black hole solutions. Therefore, my field of study is Physical Sciences, in which my main research line is Gravitational Physics and Cosmology, in particular Quantum Gravity and Quantum Cosmology, whose subfield of study is Theoretical and Mathematical Physics.

8 December 2021, 6:30pm

Neue Aula, Großer Senat

Dr. Cristóbal Pagán Cánovas (Linguistics): 'Modeling the Multimodal Flow of Human Communication: Big Data and Novel Quantitative Approaches'

Abstract
How should we model the daunting complexity of human communication? This talk explores new answers to this question through two ongoing studies, which I am developing with Professor Harald Baayen from Tübingen. The first is on the semantics of speech and gesture using generalized additive models, a statistical method particularly suitable for dealing with highly variable data, such as those of oral conversations. The data are extracted from the Red Hen Lab’s NewsScape Library, which allows us to analyze multiple videos of people uttering exactly the same words. The second study uses machine-learning techniques based on the idea of discriminative learning, in order to create a model that can associate chunks of an oral poetic performance with appropriate meanings, without introducing any knowledge about linguistic patterns such as words, phrases, or morphemes. The theoretical proposal that I am exploring suggests a holistic view of the communicative signal as a multimodal flow of low-level features (articulatory, gestural, acoustic, etc.) that anchor meaning directly on action, with no need of intermediate, discrete units in the mind.

Worried about the technicalities? Don’t be: I will strive to make this meaningful for Humanists with a minimal data science background, and vice versa.

Bio
Cristóbal Pagán Cánovas is a Ramón y Cajal Assistant Professor at the English Department, University of Murcia, an Alexander von Humboldt Fellow in Quantitative Linguistics, University of Tübingen, and a member of the International Distributed Little Red Hen Lab™. He works on cognition and poetics, conceptual integration, 4E cognition, time across language and the arts, oral poetry, and multimodal communication.

Dr. Sourabh Nampalliwar (Physics): 'Shining X-rays on the Nature of Gravity'

Abstract
Einstein’s theory has been the standard theory of gravity for nearly a century. However, it suffers from certain shortcomings which has motivated the search for alternatives to Einstein's theory. The possibility to test these alternatives around black holes has become possible very recently with advances in experimental techniques. In particular, X-rays from black hole neighborhoods carry a strong imprint of the nature of gravity around black holes. In this talk, I will first draw a simple picture of this experimental technique. Using this simple picture, I will then describe what we know so far about the nature of gravity around black holes and what we expect to find in the future.

Bio
I am a theoretical astrophysicist working mostly on black holes. I received my Ph.D. from the University of Texas in San Antonio, USA. Before joining the group in Tübingen, I was a postdoc in Shanghai. I explore different ways of looking at signals from black hole neighborhoods and using that signal to learn the nature of physical reality.

12 January 2022, 6:30pm

Neue Aula, Großer Senat

Dr. Nicolas De Maeyer (Theology): 'The Construction of Patristic Authority in the Middle Ages: the 'Sermones ad populum' of Augustine of Hippo'

Abstract
It is generally acknowledged that the writings of the Latin Church Fathers (4th-8th centuries) had a tremendous impact on the development of Christian society and European intellectual life during the Middle Ages. However, it is usually forgotten that the main vehicle for the transmission and reception of the Church Fathers’ thinking were not so much their doctrinal treatises (such as Augustine’s City of God or Gregory the Great’s Morals on the Book of Job) but rather the many thousands of sermons and homilies which they preached to their congregations during diverse liturgical occasions and which, once written down, started circulating in collections, disseminated via thousands of Medieval manuscripts. Unlike doctrinal treatises, which were read only by the intellectual elite of the time, sermons had a large and diversified audience, thus effectively serving as the ‘mass media’ of the Middle Ages.

This presentation analyses the Medieval transmission and reception of the sermons of Augustine of Hippo (354-430), in order to show how these texts shaped and influenced the image of Augustine as an authoritative writer and thinker in the Middle Ages. Several case studies will demonstrate how the circulation, adaptation, combination, and interpretation of Augustinian sermons in the manuscripts reflect and determine the Medieval reception of Augustine, while also illustrating the challenges that philologists encounter when they attempt to reconstruct the Medieval transmission of texts and ideas.

Bio
Nicolas De Maeyer studied Classical and German philology at the University of Leuven, and received his PhD in Latin Literature from the same university (2019), with a dissertation on the Venerable Bede’s Pauline commentary. He is currently postdoctoral researcher at the universities of Leuven and Tübingen, with a project on Augustine of Hippo’s Sermones de diuersis. His field of research is the transmission and reception of Patristic literature in Late Antiquity and the Middle Ages, with a particular focus on the works of Augustine of Hippo, (pseudo-)Augustinian sermons, Patristic florilegia, Latin homiliaries, and the reconstruction of Medieval libraries. For the Series Latina of the Corpus Christianorum (Brepols Publishers), he is preparing an edition of Bede’s Pauline commentary and of Augustine’s Sermones de diuersis.

Dr. Roberta Locatelli (Philosophy): The Puzzle of Colour and the Perspectival Nature of Perception

Abstract
Colours are puzzling. On the one hand, they strike us as properties of physical objects around us, objects that exist independently of us perceiving them. On the other hand, colours seem inextricably tied to perception: different species perceive them different—and what is it for something to be (let’s say) red, if not the fact that it appears that way to some perceiver? While both intuitions are individually compelling, they are in tension. Accordingly, most metaphysical accounts of colours resolve to accommodate only one of the two intuitions, while trying to convince us that it is okay to relinquish the other. The problem of colour seems so intractable because philosophy has for so long assumed that perception is like a transparent window onto the world. This poses unreasonable and unattainable constraints on what it is for a property to be objective, namely that it is conveyed to us without any ‘filter’. Replacing this assumption with a model of perception that takes seriously its perspectival nature holds the key to solving the puzzle of colour.

Bio
Roberta Locatelli is an Alexander von Humboldt Fellow at the philosophy department of the University of Tübingen. Before that, she was a postdoctoral DAAD PRIME Fellow at the same department. She earned her doctorate from the University of Warwick and the University Paris-1. She works in the philosophy of mind & psychology, with a specific focus on the philosophy of perception, and on the metaphysics of colour and other observational properties.

9 February 2022, 6:30pm

Neue Aula, Großer Senat

Dr. Carolina Carrasco Pulido (Biophysics): 'Studying DNA-Rad52 Interaction at the Single Molecule Level'

Abstract
Single-molecule biophysics combines molecular biology, physics and engineering sciences in an attempt to overcome the limitations from averaging in bulk assays. Single-molecule techniques provide useful molecular information related to structure, dynamics and function of proteins that is usually hidden in ensemble-averaged measurements. Some single-molecule techniques provide the unique ability to apply forces to DNA-protein complexes and analyze their mechanical response. Proper DNA repair is essential for cell survival and prevention of carcinogenesis. Therefore, cells possess robust mechanisms to repair DNA breaks that involve DNA manipulation by proteins. A key step of the homologous recombination mechanism is DNA annealing that is promoted by single-strand annealing proteins mediating the formation of base-pairs between complementary single-stranded DNA regions. To address how human Rad52 interacts with DNA to perform the annealing, I use a state-of-the-art Optical Tweezers setup where a single DNA molecule is mechanically stretched by performing force spectroscopy. We observed the formation of DNA-Rad52 filaments as highly stable structures where a binding mechanism by protein intercalation is proposed.

Bio
Carolina Carrasco studied Physics at the University of Granada. Because of her interest in the field of single-molecule biophysics, she moved to Madrid to obtain her PhD in Physics at the Universidad Autónoma de Madrid by studying the mechanical response of single viruses upon deformation with Atomic Force Microscopy. After that, she extended her expertise to the Magnetic Tweezers technique at the National Centre of Biotechnology (CNB-CSIC) at Madrid. Her research is focused on understanding DNA repair and replication by motor proteins at the single-molecule level. Understanding the molecular mechanisms of nanomachines is important for molecular biology and medicine because they are involved in cellular repair pathways of which defects are associated with human disease. Currently, she enjoys a Humboldt Fellowship for Experienced Researchers to study DNA-protein mechanisms by using Optical Tweezers at the Cellular Nanoscience Department in the ZMBP, Tübingen University.

Dr. Rodolfo Palomo-Briones (Geosciences): 'Production of Biofuels and Feedstocks with Anaerobic Microbiomes'

Abstract
Anaerobic technologies are a near carbon-neutral alternative for the production of fuels and chemical feedstocks of the future. Part of the interest in such technologies comes from the possibility of valorizing carbohydrate-rich residues such as lignocellulosic hydrolysates, wastewater, cheese whey, etc. On one hand, biofuels (e.g., biohydrogen) can be produced through the so-called dark fermentation, which leads to H2 and short-chain carboxylates production from carbohydrates. On the other hand, chain elongation could be coupled to the first process to take advantage of partially oxidized byproducts produced in dark fermentation to produce medium-chain carboxylates (MCC) with higher and wider market value. The direct use of carbohydrates to produce MCC is also possible. In any case, the complete comprehension of the processes and the strategies to control the microbial pathways is a pending task, especially in open culture microbiomes. In this talk, I will give an overview of the bioprocesses leading to H2 and MCC from carbohydrates, as well as the studied strategies to better understand and control them.

Bio
I studied Biochemical Engineering from 2006 to 2010 at the Instituto Tecnológico de Morelia (Morelia, Mexico). In 2010, I did an internship at the Laboratorio de Investigación en Procesos Avanzados de Tratamiento de Aguas (UNAM, Mexico), where I did my thesis on microbial fuel cells obtaining my bachelor degree in 2011. Afterward, I began my master studies at the Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), where I investigated the methanol biofiltration coupled to heterologous proteins production. Derived from that work, I obtained my master’s degree in 2013. From 2013 to 2014, I worked as an associate researcher in a project aiming to assess wastewater reuse in gold mining activities (San Luis Potosi, Mexico). Then, from 2015 to 2018, I conducted my doctoral studies at IPICYT about microbial communities in dark fermentative reactors. With such work, I obtained my doctoral degree in 2018. In 2021, I was granted a Georg Forster Research Fellowship to investigate the chain elongation process at the University of Tübingen.