In order to preserve the structure, and thus the function, of proteins and protein complexes, evolution must mutate amino-acids carefully, trying to introduce concerted changes (e.g. positive/negative charge contact turns into negative/positive charge contact). The simultaneous analysis of the sequences of the same protein from a multitude of organisms highlights where these correlated...
We introduce a numerical scheme to evolve functional elastic materials that can accomplish a specified mechanical task. In this scheme, the number of solutions, their spatial architectures and the correlations among them can be computed. As an example, we consider an "allosteric" task, which requires the material to respond specifically to a stimulus at a distant active site. We find that...
Bacteria and mitochondria share a common ancient evolutionary history, and their division processes involve a similar sequence of shape changes, before they pass through a singular point on their way to becoming two. Nonetheless, as bacteria and mitochondria divide, their composite envelopes are shaped by dramatically different constraints and forces. Bacteria control and maintain their size...
Conventional optical coherence tomography (OCT) employs a single illumination/detection channel to obtain 3D-data-sets of transparent or translucent samples. Our research focuses on the application of multiple channels for OCT in the field of ophthalmology, to help diagnose and monitor leading causes of blindness such as age-related macular degeneration, glaucoma or diabetic retinopathy. Using...
A confocal microscope equipped with a pixelated detector allows for taking images with high resolution and improved SNR. This concept has become known under the name Image Scanning Microscopy(ISM). ISM can be regarded a "multi-view" instrument, because each detector pixel provides an individual confocal image. We present the combination of ISM with generalized point spread function engineering...
Endoscopic imaging enables diagnosis and monitoring of many diseases in vivo, inaccessible to the technical means of standard imaging modalities in terms of spatial limitations. However, in the field of biomedical-optics the integration of focusing and scanning mechanisms into small endoscopes is very challenging. We therefore evaluated an endoscopic approach that may not require any lenses or...
Here practical and theoretical insights on tailoring complex fluids' properties by controlling formulation and flow-field interdependency are discussed. Viscoelastic properties depend on formulation and structure of micellar aggregates at equilibrium. The interplay between hydrophobicity and charge defines the conformation of additives, when they integrate into a micelle. Well-defined...
Mammalian gene transcription occurs stochastically in short bursts interspersed by silent intervals. However, the underlying processes and consequences on fluctuations in gene products are poorly understood. In our lab we combine time-lapse imaging of a short-lived transcriptional reporter with stochastic modeling to quantitatively characterize transcriptional bursting. While bursting kinetics...
Visco-elastic sheets have unique mechanical properties when it comes to understanding their deformation and topological changes. In the lab, we have studied the deformation of two biological visco-elastic sheets which have different spatial scales and characteristic visco-elastic times: lipid membranes, which are curved into membrane carriers in membrane transport, and epithelia, or cell...
Collective behaviour is found in wide variety of life-forms, from bacteria to humans, and it is an intriguing phenomenon with implications ranging from ecology and sociology to agriculture and artificial intelligence. I will discuss how tools from physics and machine learning can shed light on the origins and dynamics of collective motion. Specifically, I will present a model in terms of...
The use of proton therapy for cancer treatment shows a growing trend.
To direct the proton beam from all directions to the tumor in the patient, a rotatable gantry is used.
In this work we present the design of a superconducting bending magnet section for future light and compact iso-centric gantries. The coils will be wound with Nb3Sn Rutherford cables. Following the choice of a suitable...
Sharpened glass fiber – made probes attached to a quartz tuning fork exploiting the shear force–based feedback is the most popular in the field of SNOM. The use of tapping mode feedback could be preferable. Here we report such an approach realized via bent fiber probes. Detailed analysis of the vibration mode shows that an extreme caution is needed for the realization truly tapping mode. Bent...
Within the SAFIR collaboration, a high-rate PET-insert compatible with a pre-clinical 7T-MRI scanner is being developed. The SAFIR insert aims at enabling truly real-time dynamic tracer studies with unprecedented high temporal resolution of ~5s. The insert comprises 2.1x2.1x12mm3 crystals one-to-one coupled to SiPM arrays and fast-readout ASICs. At 500MBq activity, the detector is required to...
