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A functional clock in only two dorsal clock neurons is sufficient to restore the basal circadian activity pattern of Drosophila melanogaster
No full textCircadian clocks form complex networks to orchestrate the behavior and physiology of animals. Elucidating the organization of these clock networks is critical to understanding how circadian clocks achieve robust timing. Clock neurons have been best characterized in the model organism Drosophila melanogaster. At the early stages of development, Drosophila has a clock network consisting of only nine neurons per hemisphere. This set of clock neurons consists of lateral and dorsal neurons and persists in the adult fly, in which the clock network is greatly expanded to a total of ~240 neurons. The function of the early-born lateral clock neurons is well established in the adult fly. They control morning and evening activity and are responsible for circadian rhythmicity under constant conditions. Only recent studies have begun to dissect the function of the dorsal clock neurons. Using clock rescue experiments, we show here that a functional clock in only four of them, the DN1a, is sufficient to restore a bimodal locomotor activity pattern and rhythmic activity under constant conditions in the adult fly. This is achieved by CCHa1 signaling most likely to the lateral morning neurons, which are considered the main pacemakers of the clock, and by glutamate signaling to the lateral evening neurons. Interestingly, all the neurons involved are part of the early-born clock network, strongly suggesting that a core clock is already formed during early development. This set of clock neurons appears sufficient in the adult fly to drive the basal circadian activity pattern
Temperature-induced shifts and temperature compensation in the tuning of motion-sensitive neurons of bumblebees
No full textSupplemental figures S1-S3 for Jaske et al.: Temperature-induced shifts and temperature compensation in the tuning of motion-sensitive neurons of bumblebees
Abstract
Bumblebees are poikilothermic insects, i.e., their body temperature generally follows the ambient temperature. However, within certain boundaries, bumblebees are able to increase their body temperature above the ambient temperature through shivering thermogenesis. Biophysical processes, including neuronal activity, depend on temperature. In the past, the influence of temperature on sensory systems and neuronal coding was investigated in different insect species. Most studies described a temperature dependency of neuronal responses. Yet, some behavioural processes require robust encoding of information. Here we investigated the influence of temperature on the tuning of wide-field motion-sensitive neurons in the central brain of bumblebees. Using multi-unit recordings, we examined neuronal tuning properties to translational motion by presenting moving gratings at two head temperature conditions. While the tuning of most neurons showed a temperature dependency, some neurons stayed unaffected within the tested temperature range. In a third group of neurons the tuning was not affected by temperature for one movement-direction of the stimulus, while the response to the opposite direction was temperature-dependent. These different response types might serve different behavioural functions. Neurons that are involved in the control of self-motion might require temperature dependent response properties, because bumblebees fly faster at higher temperatures and therefore experience faster optic flow. Other behaviours that rely on optic flow (e.g. measuring distance travelled) require a robust, temperature-independent encoding of optic flow information. Hence, neurons that respond largely independently of temperature are required for this task. Our findings suggest a function-dependent level of temperature compensation in different populations of motion-sensitive neurons
Dissertation Constantin Meyer: Planning Support System (Python-Notebooks)
No full textIm Rahmen der Dissertation "Zonierungsmodelle als Baustein Alpiner Raumordnung: Entwicklung planungsunterstützender multikriterieller GIS-Methoden im Hinblick auf eine potenzielle Weiterentwicklung des Bayerischen Alpenplans" an der Julius-Maximilians-Universität Würzburg wurde vom Verfasser ein Planning Support System (PSS) für die überörtliche Raumordnung im Bayerischen Alpenraum entwickelt. Das PSS hat zum Ziel, eine mögliche Weiterentwicklung des Bayerischen Alpenplans durch eine umfassende Berücksichtung fachlicher Kriterien in verschiedenen Themenbereichen zu unterstützen.Die Dissertation wurde durch die Förderung einer Promotionsstelle bei der Akademie für Raumentwicklung in der Leibniz-Gemeinschaft (ARL) ermöglicht
The magnetic domain structure of holmium films at low temperatures
No full textIn spite of the widespread use of rare-earth metals in magnetism, real space investigations of their magnetic domain structures remain scarce. Here we report on a systematic investigation on the structural and magnetic properties of Ho films by means of low-temperature spin-polarized scanning tunneling microscopy (SP-STM). The films are grown on W(110), resulting in well-ordered surfaces with stacking faults, glide dislocations, and double screw dislocations, all characteristic for epitaxial growth of hcp(0001) films on bcc(110) substrates. At low coverage up to ≈ 50 atomic layers (AL), the surface magnetic structure of the Ho(0001) films is found to be dominated by ferromagnetic in-plane domains magnetized along six equivalent high-symmetry axes. Significant pinning of domain walls to crystalline defects is observed. For Ho coverages exceeding 50 AL, additional out-of-plane magnetized stripe domains superimposed to the in-plane magnetization are observed. We relate these stripe domains to the dipolar stray field associated with the known helical magnetic cone structure of Ho which leads to an uncompensated magnetization component along the c axis, i.e., perpendicular to the surface. Domain wall analysis suggests Néel-capped Bloch-type walls with widths of w_60 ≈ 1.2 nm, w_120 ≈ 3 nm, and w_180 ≈ 4 nm for 60°, 120°, and 180° walls, respectively. Magnetic field-dependent measurements reveal that the stripe domains are annihilated by an out-of-plane field of μ_0*H = ±300 mT.We acknowledge financial support by the Deutsche Forschungsgemeinschaft (DFG, German ResearchFoundation) through Project No. 510676484 (GZ BO 1468/29-1) and under Germany’s Excellence Strategy through the Würzburg–Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter, ct.qmat (EXC 2147, Project No. 390858490).Please read the "README.txt" file for further information
Quantum Fisher information in a strange metal
No full textProcessed data (including ones used for generating the figures) from theoretical calculations in the manuscript: "Quantum Fisher information in a strange metal" on https://arxiv.org/abs/2403.12779. Please read the 'README.md' file.We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086). We also acknowledge funding from the Deutsche Forschungsgemeinschaft via Grant No. AS120/16-1, Project No. 493886
Initial Sample of Color Combinations for Emotion Expression with the Pepper Robot
No full textTo investigate the usage of colored light in human-robot interaction with the Pepper robot facilitating emotion recognition from bodily expressions, we used this sample of photographed light combinations illuminating the expressions to validate them reflecting the eight inner sub-emotions from Plutchik’s wheel of emotions. For each subemotion, we created three different light combinations based on related works using two Tapo smart lights – one as an ambient and one as a spot light. In total, 24 pictures of the bodily expressions combined with colored light were shot using constant angle and background. Participants assigned emotion labels to pictures included in this repository. For further information please refer to our works referenced in the metadata
Electron Transfer and Exchange Interaction in Mixed Valence Radical Anions, Radical Cations, and Neutral Diradicals Derived from Bridged Bis-Triarylmethyl Systems_DFT
No full textThis dataset contains DFT and TD-DFT output files on neutral diradicals, cationic mixed valence compound and anionic mixed valence compounds discussed in the publication "Electron Transfer and Exchange Interaction in Mixed Valence Radical Anions, Radical Cations, and Neutral Diradicals Derived from Bridged Bis-Triarylmethyl Systems"
Raw_Data_Publication_Jonas_Erhardt_2025
No full textRaw data used for the manuscript: 'Backscattering in Topological Edge States Despite Time-Reversal Symmetry'. Data folders are organized as figures appearing in the publication. Please read the corresponding 'README' file attached.We thank C. Li for helpful discussion. We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086). Gianni Profeta acknowledges financial support by the European Union – NextGenerationEU, Project code PE0000021 - CUP B53C22004060006 - “SUPERMOL”, “Network 4 Energy Sustainable Transition – NEST” and the European Union - NextGenerationEU under the Italian Ministry of University and Research (MUR) National Innovation Ecosystem grant ECS00000041 - VITALITY - CUP E13C22001060006.Contrary to the idealized notion of linear edge bands, the non-monotonic dispersions of realistic QSHI materials can host multiple Kramers pairs, reintroducing backscattering channels between them without violating time-reversal symmetry. Here, we investigate inter-Kramers pair backscattering in the non-linear edge bands of the QSHI indenene, highlighting a critical aspect of edge-state stability
Probing chiral symmetry with a topological domain wall sensor
No full textChiral symmetry is a fundamental property with profound implications for the characteristics of elementary particles, that implies a spectral symmetry (i.e. E -> -E ) in their dispersion relation. In condensed matter physics, chiral symmetry is often associated with superconductors or materials hosting Dirac fermions, such as graphene or topological insulators. In these contexts, chiral symmetry is an emergent low-energy property, accompanied by an emergent spectral symmetry. However, since the presence of spectral symmetry does not necessarily imply chiral symmetry, a key question arises: how can these two properties be experimentally differentiated? In this study, we demonstrate that a system with preserved spectral symmetry can reveal underlying broken chiral symmetry through the presence of topological defects. Our findings shows that these defects induce a spectral imbalance in the Landau level spectrum, providing direct evidence of symmetry alteration at topological domain walls. Using high-resolution scanning tunneling microscopy and spectroscopy, we demonstrate the intricate interplay between chiral and translational symmetry, which is broken at step edges in topological crystalline insulator PbSnSe. The chiral symmetry breaking leads to a shift in the guiding center coordinates of the Landau orbitals near the step edge, thus resulting in a distinct chiral flow of the spectral density of Landau levels. This study underscores the pivotal role of topological defects as sensitive probes for detecting hidden symmetries, offering insights into emergent phenomena with implications for fundamental physics.We acknowledges funding supported by Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through SFB 1170 Project No. 258499086 (project C02) and the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter – ct.qmat (EXC 2147, Project No. 390858490). T.N. acknowledges support from the Swiss National Science Foundation through a consolidator grant (iTQC, TMCG-2-213805). R.T. and T.N. acknowledge support from the FOR 5249 (QUAST) led by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), in Switzerland funded by the Swiss National Science Foundation (Project 200021E-198011). G.W. acknowledges funding from the University of Zurich postdoc grant FK-23-134. The work of J.K. and T.S. was supported by the Foundation for Polish Science project “MagTop” no. FENG.02.01-IP.05-0028/23, co-financed by the European Union from the funds of Priority 2 of the European Funds for a Smart Economy Program 2021–2027 (FENG)
Single-Photon Source in a Topological Cavity
No full textThe data repository can create the figures of the publication Jurkat et al. Single-Photon Source in a Topological Cavity. Nano Lett. 23, 820–826 (2023). All relevant information on the science can be found in the publication. In the publication we investigate the coupling of a single optically active semiconductor quantum dot to the zero-dimensional topological protected defect at the end of a Su-Shrieefer-Heeger chain, which is composed of a zig-zag chain of coupled microresonators. For more details, please refer to the original publication.The Wurzburg group acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)INST 93/1007-1 LAGG and INST 93/1025-1 FUGG and financial support under Germany’s Excellence StrategyEXC2147 “ct.qmat” (Project No. 390 858 490) and is grateful for support by the state of Bavaria. C.S. and S.K. acknowledge funding by the DFG within the projects SCHN1376 13.1 and KL3124 3.1 (El Pollo Loco). T.H.L. acknowledges funding by the German ministry for research and education (BMBF) through the Quantum Futur initiative Qecs (13N16272)