Search results for " Fluorescence"
showing 10 items of 1097 documents
Research data supporting 'Short hydrogen bonds enhance nonaromatic protein-related fluorescence'
2021
Raw data for experimental figures. Files contain .cif (crystallographic information file) for XRD data of the L-pyro-amm structure. .xlsx file containing spectra for absorption of L-glutamine, L-pyroglutamine and L-pyro-amm. .xlsx file contains spectra for fluorescence excitation and emission collected over 8 days for L-glutamine conversion to L-pyro-amm.
Ligand-Centred Fluorescence and Electronic Relaxation Cascade at Vibrational Time Scales in Transition-Metal Complexes
2015
Using femtosecond-resolved photoluminescence up-conversion, we report the observation of the fluorescence of the high-lying ligand-centered (LC) electronic state upon 266 nm excitation of an iridium complex, Ir(ppy)(3), with a lifetime of 70 +/- 10 fs. It is accompanied by a simultaneous emission of all lower-lying electronic states, except the lowest triplet metal-to-ligand charge-transfer ((MLCT)-M-3) state that shows a rise on the same time scale. Thus, we observe the departure, the intermediate steps, and the arrival of the relaxation cascade spanning similar to 1.6 eV from the (LC)-L-1 state to the lowest 3MLCT state, which then yields the long-lived luminescence of the molecule. This …
Briofītu inducētās izturības pētījumi ar hlorofila a fluorescences analīzes metodi
2015
Darbā aprakstīti briofītu pielāgošanās mehānismi sarežģītiem dzīves apstākļiem. Mērķis bija noskaidrot, vai nepārtrauktā hlorofila a fluorescence ir izmantojama, lai noteiktu briofītu inducēto izturību. Pētījums sastāv no divām daļām. Lai noteiktu briofītu izžūšanas izturību un iespēju izmantot hlorofila a fluorescences metodi tās novērtēšanai, ievāktas trīs sugas, kurām veikta fluorescences analīze paraugu izžūšanas laikā. Lai noteiktu briofītu fluorescences rādītājus briofītiem dažādās temperatūrās, ievāktas 4 sugas. Darbā secināts, ka nepārtraukto hlorofila a fluorescenci ir iespējams izmantot, lai noteiktu briofītu inducēto izturību. Iegūtie fluorescences dati norāda uz izmaiņām briofīt…
Influence of Nanoparticle Exposure on Nervous System Development in Zebrafish Studied by Means of Light Sheet Fluorescence Microscopy
2016
Zebrafish has a remarkable similarity in the molecular signaling processes, cellular structure, anatomy and physiology to other higher order vertebrates, making it an excellent vertebrate model organism (1). Recently, zebrafish has been used for neurotoxicity screening of numerous nanomaterials with a focus on the developmental effects due to the possibility of in vivo visualization of specific neurons and axon tracts by injecting dyes in live animals as well in fixed ones (2). Here we propose Light Sheet Fluorescence Microscopy (LSFM) (3) (4) to perform neurotoxicity studies, in order to study the nervous system architecture and to image 3D structures in the brain of live larvae during the…
A Novel Fast Volumetric Light Sheet Microscopy
2016
Fast noninvasive three-dimensional (3D) imaging is crucial for the quantitative understanding of highly dynamic biological processes. Over the last decades, several fluorescence microscopy techniques have been developed in order to provide a faster and deeper imaging of thick biological samples [1]. Within this framework, Light Sheet Fluorescence Microscopy (LSFM) has emerged as a powerful imaging tool for 3D imaging of thick samples ranging from single cells to entire animals [2,3].However, to obtain a 3D reconstruction either sample or microscope parts usually need to be moved limiting the acquisition speed and inducing possible interferences in volume recording. To solve this problem, he…
Apoptotic-like Leishmania exploit the host´s autophagy machinery to reduce T-cell-mediated parasite elimination
2015
Apoptosis is a well-defined cellular process in which a cell dies, characterized by cell shrinkage and DNA fragmentation. In parasites like Leishmania, the process of apoptosis-like cell death has been described. Moreover upon infection, the apoptotic-like population is essential for disease development, in part by silencing host phagocytes. Nevertheless, the exact mechanism of how apoptosis in unicellular organisms may support infectivity remains unclear. Therefore we investigated the fate of apoptotic-like Leishmania parasites in human host macrophages. Our data showed--in contrast to viable parasites--that apoptotic-like parasites enter an LC3(+), autophagy-like compartment. The compartm…
Rb atomu leņķiskā momenta šķērsorientācijas eksperimentāli pētījumi ārējā magnētiskajā laukā, ierosinot D1 līnijas supersīkstruktūras pārejas
2020
Šajā darbā tiek pētīta rubīdija leņķiskā momenta izkārtošanas pāreja šķērsorientācijā, ko rada Rb D_1 līnijas supersīkstruktūras līmeņu mijiedarbība ar gaismu magnētiskajā laukā. Šis efekts tika konstatēts eksperimentāli, mērot divu atsevišķu, pretēji cirkulāri polarizētu lāzera inducētās fluorescences komponenšu signālu starpības. Tika iegūtas šo signālu atkarības no lāzera frekvences un intensitātes. Iegūtie eksperimentālie dati tika salīdzināti ar teorētiskajiem, kas iegūti, izmantojot LU Lāzeru Centrā attīstītu teorētisko modeli. Papildus tam tika analizēti eksperimentālo signālu veidošanās un to formas cēloņi, kā arī to saistība ar supersīkstruktūras magnētisko apakšlīmeņu pāreju uzved…
Micro-X-Ray Fluorescence and the Old Masters Non-destructive in situ characterisation of the varnish of historical Low Countries stringed musical ins…
2012
Applied Physics A, 107
Zein as biodegradable material for effective delivery of alkaline phosphatase and substrates in biokits and biosensors
2016
A biodegradable material, zein, is proposed as a reagent delivery platform for biokits and biosensors based on alkaline phosphatase (ALP) activity/inhibition in the presence of phosphatase substrates. The immobilization and release of both the substrate and/or the active ALP, in a biodegradable and low-cost material such as zein, a prolamin from maize, and in combination with glycerol as plasticizer have been investigated. Three zein-based devices are proposed for several applications: (1) inorganic phosphorus estimation in water of different sources (river, lake, coastal water and tap water) with a detection limit of 0.2mg/L - compared to at least 1mg/L required by legislation, (2) estimat…
Fab fragments from a monoclonal antibody against a germ tube mannoprotein block the yeast-to-mycelium transition in Candida albicans.
1990
Fab fragments prepared from the immunoglobulin G monoclonal antibody (MAb) 4C12, which reacts with a determinant expressed on the hyphal extension of germ tubes of Candida albicans, inhibited germ tube formation, but intact MAb 4C12 did not. Indirect immunofluorescence showed a punctate binding pattern on cells incubated with Fab fragments but a confluent binding on cells incubated with intact MAb 4C12.