Conference Agenda

The progression of fibrosis is frequently related to a failed healing process, and it may affect many tissues and organs causing severe consequences including post-infarct heart insufficiency, post-injury limb paralysis, cirrhosis, nephropathy, retinopathy, failure of implanted devices and even resistance to chemotherapy in solid tumours. Experimental models, both in vitro and in vivo, are widely used for studies of basic pathophysiology, and for pre-clinical testing of pharmacological therapies counteracting fibrosis. However, conventional models are not able to realistically reproduce the revascularization aspect of the inflammatory reaction that leads to the generation of fibrotic tissue. In this talk, I will present the most advanced frontier in this sector, represented by the new concept of an "organism-on-a-chip". This is a hybrid model, in which an organ-on-a-chip is implanted sub-cute in a living organism, such as a mouse or an embryonated avian egg, thus eliciting a foreign-body reaction with the formation of a fibrotic microenvironment. In an organism-on-a-chip, the fibrotic reaction can be guided in terms of extra-cellular stiffness and vascularity, using microscopic scaffolds incorporated in the implanted chip. The fibrotic microenvironment can then be imaged longitudinally, in high resolution, with the added advantage of significantly reducing animal sacrifice.

We present how to develop virtual microcylinder- or microsphere-assisted surface topography measurement instruments. As the most critical part, the interaction between light, microcylinder and measurement object is considered based on the finite element method (FEM). Results are obtained for microcylinder-assisted conventional, interference, and confocal microscopes without necessity to repeat the time-consuming FEM simulations for each sensor.

Topographical as well as microscopic imaging of nanoscale surfaces plays a pivotal role across various disciplines. Nevertheless, achieving fast, label-free, and accurate characterization of laterally expanded structures below the diffraction limit remains challenging. Recent studies highlight the use of microsphere assistance for resolution improvement. Confocal microscopy, augmented by microspheres, enables the imaging of small structures that were previously inaccessible. This is experimentally compared with microsphere-assisted microscopy (MAM) to underline the decisive role of the confocal effect.

Nearfield spectroscopy is crucial for characterizing micro- and nanostructures and it often requires hyperspectral imaging, where at each spatial point a full spectrum is recorded. Due to its combination with an atomic force microscope, nearfield hyperspectral imaging is serial in nature and results in long acquisition times and stability challenges, also restricting its industrial use. In this work, we employ a subsampling strategy combined with low-rank matrix reconstruction in a commercial nearfield spectroscopy system to significantly shorten measurement acquisition times.

Optical vortices, characterized by their helical phase topology and ability to carry orbital angular momentum, have found diverse applications in metrology. In this work, we present novel metrology systems utilizing vortex beams. The adaptation of optical vortex microscopy for rough surface measurement using fluorescent nanomarkers, and experimental setup for retardation measurement are described. Retardation measurement has been successfully applied to the calibration of spatial light modulator and can be adapted for measurement of circular dichroism. In developed methods the information on retardation or local surface height is restored from self-interference spread function of optical vortex beams carrying opposite topological charges, called Double-Helix Point Spread Function (DH PSF). The use of neural networks, enhancing measurement accuracy and enabling advanced data analysis for data processing, is described.