BImplementation of photonic true time delay using high-order-mode dispersion compensating fibers

Abstract-We demonstrate the advantageous use of highly dispersive ( 450 ps nm km), high-order-mode (HOM) fiber modules for true time delay applications. Along with their low insertion loss, very low phase ripple (root mean square 0 3 over 0-20 GHz), and high immunity to nonlinear effects, the high dispersion values facilitate the construction of devices with relatively short fibers, resulting in improved tolerance of the radio frequency delay to thermal changes. The implications of multiple path interference effects in HOM modules are also studied and shown to be very small

Analysis of a true time delay photonic beamformer for transmission of a linear frequency-modulated waveform

Citation for published version (APA): Rotman, R., Raz, O., & Tur, M. (2005). Analysis of a true time delay photonic beamformer for tranmission of a linear frequency-modulated waveform. Journal of Lightwave Technology, 23(12) Please check the document version of this publication: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement: www.tue.nl/taverne Take down policy If you believe that this document breaches copyright please contact us at: [email protected] providing details and we will investigate your claim. Abstract-A generalized conversion matrix (GCM) and numerical analysis are used to study the distortions suffered by a linear frequency-modulated radio frequency (RF) pulse while propagating through photonic links to be used in wideband phased arrays. The analysis shows the effects of dispersion of all orders, coherent crosstalk and nonlinearity of the optical components on the RF pulse, and the high performance needed to achieve acceptable RF performance of the temporal (impulse) response. The effects of the electrical-to-optical (E/O) and optical-to-electrical (O/E) conversions are also considered. Using the GCM, the optical amplitude and phase fluctuations are converted into their RF counterparts, thereby reducing the optical problem into the wellunderstood RF domain. A photonic wavelength-controlled true delay device is experimentally shown to achieve good RF performance over a 4-GHz bandwidth, with predicted sidelobe levels below 30 dB

HUVEC were exposed to 0, 2 and 4 meshes for 2, 5 and 10 minutes.

<p>Extra-cellular vWF strings were labeled with anti-vWF antibodies (green) and cells' nuclei with DAPI (blue). Representative confocal images of mechanical pressure induced—vWF release from HUVEC for (A). x25 magnification and (B). x63 magnification, were imaged by confocal laser scanning microscopy. Bars represent 50 μm and 20 μm for x25 and x63 magnifications, respectively.</p

Filippo Pigafetta (Duarte Lopes) - 1591. Italienischer Text. Wiener Studien|Michael Boyms Bericht aus Mosambik - 1644|

<div><p>Short peripheral catheters are ubiquitous in today's healthcare environment enabling effective delivery of fluids and medications directly into a patient's vasculature. However, complications related to their use, such as short peripheral catheter thrombophlebitis (SPCT), affect up to 80% of hospitalized patients. While indwelling within the vein, the catheters exert prolonged constant pressure upon the endothelium which can trigger inflammation processes. We have developed and studied an in-vitro model of cultured endothelial cells subjected to mechanical compression of modular self-designed weights, and explored their inflammatory response by quantification of two key biomarkers- vWF and IL-8. Evaluation was performed by ELISA immunoassay and processing of vWF-labeled immunofluorescence images. We found that application of weights correspond to 272 Pa yielded increased release of vWF and IL-8 up to 150% and 250% respectively, comparing to the exertion of 136 Pa. Analyses of the immunofluorescence images revealed significantly longer and more extracellular vWF-strings as well as higher intensity stained-pixels in cells exposed to elevated pressures. The release of both factors found to be significantly dependent on the extent of the exerted pressure. The research shed a light on the relationship between induced mechanical compression and the pathogenesis of SPCT. Minimizing, let alone eliminating the contact between the catheter and the vein wall will mitigate the pressure acting on the endothelium, thereby reducing the secretion of inflammatory factors and lessen the incidence of SPCT.</p></div