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Processive enzymes like polymerases or ribosomes are often studied in bulk experiments by monitoring time-dependent signals, such as fluorescence time traces. However, due to biomolecular process stochasticity, ensemble signals may lack the distinct features of single-molecule signals. Here, we demonstrate that, under certain conditions, bulk signals from processive reactions can be decomposed to unveil hidden information about individual reaction steps. Using mRNA translation as a case study, we show that decomposing a noisy ensemble signal generated by the translation of mRNAs with more than a few codons is an ill-posed problem, addressable through Tikhonov regularization. We apply our method to the fluorescence signatures of in-vitro translated LepB mRNA and determine codon-position dependent translation rates and corresponding state-specific fluorescence intensities. We find a significant change in fluorescence intensity after the fourth and the fifth peptide bond formation, and show that both codon position and encoded amino acid have an effect on the elongation rate. This demonstrates that our approach enhances the information content extracted from bulk experiments, thereby expanding the range of these time- and cost-efficient methods.

Optical coherence tomography (OCT), a non-contact, non-destructive imaging technique, is becoming a popular tool in phytophotonics, helping to address research questions in plant biology and horticulture. However, the stationary nature of typical OCT systems compromises its non-destructive advantage since plants often need to be dissected for an analysis with a laboratory OCT system. Here we present a portable, low-cost OCT system that enables in-situ measurements of plants. We outline technical challenges encountered during the development and showcase initial measurements of different plant tissues. Copyright 2024 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.

Oxidative stress is a cause for numerous diseases and aging processes. Thus, researchers are keen to tune the level of intracellular stress and to learn from that. An unusual approach is presented here. The methodology involves multifunctional surfactants. Although their molecular design is nonbiological—a fullerenol head group attached covalently to pi-conjugated dyes—the surfactants possess superior biocompatibility. Using an intrinsic fluorescence signal as a probe, it is shown that the amphiphiles become incorporated into the Caco-2 cells. There, they are able to exhibit additional functions. The compound reduces cellular stress in dark reaction pathways. The antagonistic property is activated under irradiation, the photocatalytic production of reactive oxygen species (ROS), resulting in cell damage. The feature is activated even by near-infrared light (NIR-light) via a two-photon process. The properties as molecular semiconductors lead to a trojan horse situation and allows the programming of the spatial distribution of cytotoxicity.

Hyperspectral imaging is a key technology for monitoring agricultural crops and vegetation. It can be used for health estimation and the early detection of disease symptoms in plants. This can help to reduce the use of pesticides by allowing targeted and early intervention. Cost-efficient hyperspectral imaging systems are necessary to meet the increasing demand for monitoring techniques for agricultural products. These systems usually suffer from sub-optimal image quality. Here we present a digital aberration correction for hyperspectral image data. Copyright 2023 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.

Plant in vitro culture techniques comprise important fundamental methods of modern plant research, propagation and breeding. Innovative scientific approaches to further develop the cultivation process, therefore, have the potential of far-reaching impact on many different areas. In particular, automation can increase efficiency of in vitro propagation, a domain currently con-strained by intensive manual labor. Automated phenotyping of plant in vitro culture bears the potential to extend the evaluation of in vitro plants from manual destructive endpoint measurements to continuous and objective digital quantification of plant traits. Consequently, this can lead to a better understanding of crucial developmental processes and will help to clarify the emergence of physiological disorders of plant in vitro cultures. The aim of this dissertation was to investigate and exemplify the potential of optical sensing methods and machine learning in plant in vitro culture from an interdisciplinary point of view. A novel robotic phenotyping system for automated, non-destructive, multi-dimensional in situ detection of plant traits based on low-cost sensor technology was con-ceptualized, developed and tested. Various sensor technologies, including an RGB camera, a laser distance sensor, a micro spectrometer, and a thermal camera, were applied partly for the first time under these challenging conditions and evaluated with respect to the resulting data quality and feasibility. In addition to the development of new dynamic, semi-automated data processing pipelines, the automatic acquisition of multisensory data across an entire subculture passage of plant in vitro cultures was demonstrated. This allowed novel time series images of different developmental processes of plant in vitro cultures and the emergence of physiological disorders to be captured in situ for the first time. The digital determination of relevant parameters such as projected plant area, average canopy height, and maxi, Die pflanzliche In-vitro-Kultur umfasst wichtige grundlegende Methoden der modernen Pflanzenforschung, -vermehrung und -züchtung. Innovative wissenschaftliche Ansätze zur Wei-terentwicklung des Kultivierungsprozess können daher weitreichenden Einfluss auf viele unter-schiedliche Bereiche haben. Insbesondere die Automatisierung kann die Effizienz der In-vitro-Vermehrung steigern, die derzeit durch die intensive manuelle Arbeit beschränkt wird. Automa-tisierte Phänotypisierung von In-vitro-Kulturen ermöglicht es, die Erfassung von manuellen de-struktiven Endpunktmessungen auf eine kontinuierliche, objektive und digitale Quantifizierung der Pflanzenmerkmale auszuweiten. Dies kann zu einem besseren Verständnis entscheidender Entwicklungsprozesse führen und die Entstehung physiologischer Störungen zu klären. Ziel dieser Dissertation war es, das Potential optischer Erfassungsmethoden und des maschinellen Lernens für die pflanzliche In-vitro-Kultur unter interdisziplinären Gesichtspunk-ten zu untersuchen und exemplarisch aufzuzeigen. Ein neuartiger Phänotypisierungsroboter zur automatisierten, zerstörungsfreien, mehrdimensionalen In-situ-Erfassung von Pflanzenmerkmalen wurde auf Basis kostengünstiger Sensortechnik entwickelt. Unterschiedliche Sensortechnologien, darunter eine RGB-Kamera, ein Laser-Distanzsensor, ein Mikrospektrometer und eine Wärmebildkamera, wurden teils zum ersten Mal unter diesen schwierigen Bedingungen eingesetzt und im Hinblick auf die resultierende Datenqualität und Realisierbarkeit bewertet. Neben der Entwicklung dynamischer, halbautomatischer Datenverarbeitungspipelines, wurde die automatische Erfassung multisensorischer Daten über eine gesamte Subkulturpassage der In-vitro-Kulturen demonstriert. Dadurch konnte erstmals Zeitrafferaufnahmen verschiedener Ent-wicklungsprozesse von pflanzlichen In-vitro-Kulturen und das Auftreten von physiologischen Störungen in situ erfasst werden. Die digitale Bestimmung relevanter Kenngrößen wie der proji-zierten P

Laryngeal OCT imaging is challenging due to anatomy-dependent vocal cord position and motion artifacts caused by movements of patient and physician. We present a MHz OCT laryngoscope with variable working distance

Using Brillouin light scattering spectroscopy as a non-destructive, label-free method to determine the effects on leave biomechanics after inoculation of Diplocarpon rosea in two different resistive rose genotypes.

FD-OCT systems with non-uniform wavenumber sampling require calibration and resampling routines to achieve optimal axial resolution. We present a simple calibration procedure and provide all necessary algorithmic components for wavenumber resampling.