Search results for "Modulator"
showing 10 items of 210 documents
Spatial light modulator phase mask implementation of wavefront encoded 3D computational-optical microscopy
2015
Spatial light modulator (SLM) implementation of wavefront encoding enables various types of engineered pointspread functions (PSFs), including the generalized-cubic and squared-cubic phase mask wavefront encoded (WFE) PSFs, shown to reduce the impact of sample-induced spherical aberration in fluorescence microscopy. This investigation validates dynamic experimental parameter variation of these WFE-PSFs. We find that particular design parameter bounds exist, within which the divergence of computed and experimental WFE-PSFs is of the same order of magnitude as that of computed and experimental conventional PSFs, such that model-based approaches for solving the inverse imaging problem can be a…
Superresolved common-path phase-shifting digital inline holographic microscopy using a spatial light modulator.
2012
Common-path phase-shifting lensless holographic microscopy has been recently proposed as a novel approach capable of high numerical aperture imaging in a lensless digital inline holographic microscopy layout [Opt. Lett.35, 3919 (2010)]. Here we present proof-of-concept validation for improving the resolution limit imposed by diffraction in such a setup. This is accomplished by shifting the phase lens displayed at the spatial light modulator, which moves the illumination point source to different off-axis positions. For each off-axis position, a set of inline phase-shifted holograms are recorded by the digital sensor and stored at the computer’s memory for later digital postprocessing. As a …
Quantitative Phase Imaging in Microscopy Using a Spatial Light Modulator
2010
In this chapter, we present a new method capable of recovery of the quantitative phase information of microscopic samples. Essentially, a spatial light modulator (SLM) and digital image processing are the basics to extract the sample’s phase distribution. The SLM produces a set of misfocused images of the input sample at the CCD plane by displaying a set of lenses with different power at the SLM device. The recorded images are then numerically processed to retrieve phase information. Computations are based on the wave propagation equation and lead to a complex amplitude image containing information of both amplitude and phase distributions of the input sample diffracted wave front. The prop…
Ultra-high repetition all optical picosecond pulsed sources : applications in optical telecommunications
2013
This thesis presents the work carried out on the realization of fibered 40-GHz picosecond optical pulse sources in the telecommunications C-band. In the first part, we present a numerical and experimental study of the generation of 40-GHz pulse trains thanks to the nonlinear compression of an initial beat-signal by multiple Four-Wave Mixing process. Enhanced temporal stability is achieved by generating the sinusoidal beating thanks to a Mach-Zehnder modulator driven at its zero-transmission working point. In order to improve the quality of the generated pulses, we also demonstrate the suppression of stimulated Brillouin back-scattering by inserting several optical isolators into the compres…
Tackling Performance Challenges in Organic Photovoltaics: An Overview about Compatibilizers
2020
Organic Photovoltaics (OPVs) based on Bulk Heterojunction (BHJ) blends are a mature technology. Having started their intensive development two decades ago, their low cost, processability and flexibility rapidly funneled the interest of the scientific community, searching for new solutions to expand solar photovoltaics market and promote sustainable development. However, their robust implementation is hampered by some issues, concerning the choice of the donor/acceptor materials, the device thermal/photo-stability, and, last but not least, their morphology. Indeed, the morphological profile of BHJs has a strong impact over charge generation, collection, and recombination processes; control o…
Inhibitory control of duodenal contractility by adenosine in mice
2009
A proctolin-like peptide is regulated after baculovirus infection and mediates in caterpillar locomotion and digestion
2022
Baculoviruses constitute a large group of invertebrate DNA viruses, predominantly infecting larvae of the insect order Lepidoptera. During a baculovirus infection, the virus spreads throughout the insect body producing a systemic infection in multiple larval tissues, included the central nervous system (CNS). As a main component of the CNS, neuropeptides are small protein-like molecules functioning as neurohormones, neurotransmitters, or neuromodulators. These peptides are involved in regulating animal physiology and behavior and could be altered after baculovirus infection. In this study, we have investigated the effect of Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) infection …
Penicillium lanoso-viride AMP dezamināzi atpazīstošo receptoru klāsta detektēšana perifēro asiņu mononukleārajās šūnās
2016
Šajā darbā salīdzināta Penicillium lanoso-viride sintezētās AMPD un citu sēņu izcelsmes imūnmodulatoru un standartvielu iedarbība uz iekaisuma reakcijās iesaistītu molekulu gēnu ekspresiju un sekrēciju asins imūnsistēmas šūnās, un, balstoties uz rezultātos iegūto informāciju, veikta AMPD atpazīstošo PRR analīze. Ar RT-PCR metodi veiktās analīzes uzrāda, ka AMPD stimulētās asins imūnajās šūnās ir paaugstināta iekaisuma citokīnu, kā arī TLR4 signālceļā iesaistīto molekulu gēnu ekspresija, kas norāda uz tās iekaisumu veicinošo ietekmi. Ar receptoru bloķēšanas un ELISA proteīnu koncentrācijas noteikšanas metodes palīdzību noskaidrots, ka AMPD savu imūnmodulatoro darbību asins mononukleārajās šū…
Penicillium lanoso - viride AMP dezamināzes ietekme uz citokīnu izmaiņām pēc lielu devu I.V. ievadīšanas pelēm
2017
Adenilāta dezamināze (AMPD) ir glikoproteīns, kas ir dabisks sēņu izcelsmes imūnmodulators. To producē mikroskopiska sēnīte Penicillium lanoso - viride. Iepriekšējie pētījumi parādīja, ka attīrīts imūnmodulators AMPD uzrāda in vitro un in vivo aktivitāti, tai skaitā pozitīvu ietekmi uz brūču dzīšanu grauzējiem. Maģistra darba pētījumā tika izvērtēta ietekme uz citokīnu, limfocītu, neitrofilu un temperatūras izmaiņām pēc AMPD lielu devu i.v. ievadīšanas ICR peļu tēviņiem. Iegūtie rezultāti norāda uz AMPD īslaicīgu imūnstimulējošo iedarbību, pastiprināti inducējot citokīnu sekrēciju, limfocītu un neitrofilu skaita izmaiņas 4h pēc AMPD i.v. ievadīšanas pelēm. AMPD drošības profils ir optimāls,…
Dabīgu imūnmodulatoru kvalitātes kontroles metožu izvērtējums un stimulējošās iedarbības salīdzinājums ar baktēriju endotoksīnu
2016
Darba mērķis bija raksturot dabīga imūnmodulatora AMP dezamināzes aktivitāti saturoša glikoproteīnu kompleksa (AMPD) darbību in vitro un novērtēt, vai šī iedarbība nav saistīta ar iespējamo endotoksīna (LPS) piesārņojumu. Tika izvērtētas AMPD attīrīšanas metodes, salīdzināta AMPD, LPS un lentināna ietekme uz iekaisuma citokīnu sekrēciju mononukleārajās šūnās, kā arī uz dermas fibroblastu proliferāciju. AMPD frakcijas sastāvs un polisaharīda daļas iespējami strukturālā līdzība ar LPS sarežģīja kvalitātes kontroli. Tāpat kā LPS, AMPD stimulēja TNF un IL-6 produkciju un veicināja dermas fibroblastu proliferāciju ar imūnšūnu sekretēto proteīnu starpniecību. LPS neitralizēšanai izmantojamās met…