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Tag Archives: photons
Ambizione fellowship and an open PhD position
I’m glad to share that I am going to start my own junior research group at the University of Zurich in March 2023! As an Ambizione fellow, I will receive funding for my own salary, some equipment, consumables and a … Continue reading
Simple geometrical optics to understand and design point-scanning microscopes
Custom-built microscopes have become more and more sophisticated over the last years to provide a larger FOV, better resolution through some flavor of adaptive optics or simply more neurons simultaneously. Professional optical engineers are hired to design the ideal lens … Continue reading
Large-scale calcium imaging & noise levels
Calcium imaging based on two-photon scanning microscopy is a standard method to record the activity of neurons in the living brain. Due to the point-scanning approach, sampling speed is limited and the dwell time on a single neuron reduces with … Continue reading
Posted in Calcium Imaging, Data analysis, Imaging, Microscopy, Neuronal activity
Tagged Calcium Imaging, Data analysis, Microscopy, photons, Scanning
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Fast scanning, triplet states and photon yield
In point-scanning microscopy like two-photon or confocal microscopy, a focused laser beam is scanned across the field of view and thereby sequentially recovers an image of the object. In this blog post, I will discuss the idea that scanning faster … Continue reading
Posted in Calcium Imaging, Imaging, Microscopy, Neuronal activity
Tagged Calcium Imaging, Microscopy, photons, Scanning, zebrafish
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A practical guide for adaptive optics
There is no standard curriculum to learn practical procedures about microscopy: how to align a setup, how to identify misalignments, how to identify broken parts, where to buy components, how to check their performance, and much more. How to learn … Continue reading
Review: An artificial ground truth for calcium imaging
Selected paper: Charles, Song, Tank et al., Neural Anatomy and Optical Microscopy Simulation (NAOMi) for evaluating calcium imaging methods, bioRxiv (2019). What is the paper about? Calcium imaging is a central method to observe neuronal activity in the brain of … Continue reading
Posted in Calcium Imaging, Data analysis, Imaging, Microscopy, Neuronal activity, Reviews
Tagged Data analysis, Microscopy, photons, PSF, Scanning
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The cell-attached soundtrack of calcium imaging
Old-school electrophysiologists like to listen to the ephys signals during experiments. For example, this allows to precisely hear when the patch pipette approaches a target neuron. The technique is discussed in the Axon Guide: “Audio Monitor: Friend or Foe?”. The … Continue reading
Posted in Calcium Imaging, electrophysiology, Imaging, Neuronal activity, zebrafish
Tagged electrophysiology, Microscopy, photons, zebrafish
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Post-publication review: Somato-dendritic coupling of L5 neurons in V1
It requires more than a quick look at the abstract and the figures to fully understand a research paper and its limitations. One way to get there is to write a summary or critical review of a paper. In a contribution to … Continue reading
Posted in Calcium Imaging, electrophysiology, Microscopy, Reviews
Tagged Dendrites, electrophysiology, photons, theoretical neuroscience
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Photon yield and pulse dispersion
This case report describes how a two-photon microscope was found to come with a fluorescence yield that was lower than expected; how the underlying cause was found out in a systematic manner; and how the problem was solved. All approaches and solutions are specific for the microscope under question. However, I hope that this report (1) will inspire other people who are troubleshooting or optimizing their microscopes, (2) will help other people better understand two-photon microscopes and the relevance of technical details. Continue reading
Whole-cell patch clamp, part 4: look and feel
In previous blog posts, I have been discussing some aspects of whole-cell patch clamp recordings ([1], [2], [3], [4]). Today, I will show some instructive videos that I recorded during experiments. I’m hoping that they will convey the look and feel … Continue reading
Posted in Calcium Imaging, electrophysiology, Imaging, Microscopy, Neuronal activity, zebrafish
Tagged electrophysiology, Microscopy, photons, zebrafish
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A blog about neurophysiology 