Search results for "FOT"
showing 10 items of 1161 documents
Sulfotransferase-mediated mutagenicity of 1-hydroxymethylpyrene and 4H-cyclopenta[def]chrysen-4-ol and its enhancement by chloride anions.
1993
1-Hydroxymethylpyrene (HMP), a primary benzylic alcohol, and 4H-cyclopenta[def]chrysen-4-ol (OH-CPC), a secondary benzylic alcohol, were investigated for mutagenicity in Salmonella typhimurium (reversion of the his- strain TA98) in the presence of various xenobiotic-metabolizing systems. In the direct test, HMP was inactive and OH-CPC was very weakly active. In the presence of NADPH-fortified postmitochondrial fraction from rat liver (S9/NADPH), no activation of OH-CPC was observed, whereas strong mutagenic effects were elicited by HMP. In the presence of cytosol and 3'-phosphoadenosine-5'-phosphosulfate (PAPS), both alcohols were activated to potent mutagens. For equal mutagenic effects, a…
Triggering the generation of an iron(IV)-oxo compound and its reactivity toward sulfides by RuII photocatalysis
2014
The preparation of [FeIV(O)(MePy2tacn)]2+ (2, MePy2tacn = N-methyl-N,N-bis(2-picolyl)-1,4,7-triazacyclononane) by reaction of [FeII(MePy2tacn)(solvent)]2+ (1) and PhIO in CH3CN and its full characterization are described. This compound can also be prepared photochemically from its iron(II) precursor by irradiation at 447 nm in the presence of catalytic amounts of [Ru II(bpy)3]2+ as photosensitizer and a sacrificial electron acceptor (Na2S2O8). Remarkably, the rate of the reaction of the photochemically prepared compound 2 toward sulfides increases 150-fold under irradiation, and 2 is partially regenerated after the sulfide has been consumed; hence, the process can be repeated several times.…
Dependency of the in vitro stabilization of differentiated functions in liver parenchymal cells on the type of cell line used for co-culture.
1992
The differentiation status in cultures of primary rat liver parenchymal cells was determined by measuring the activities of various xenobiotic metabolizing enzymes. Most enzyme activities dropped rather rapidly in monocultures of parenchymal cells. The protein content and the activities of cytosolic epoxide hydrolase, glutathione S-transferase, and alpha-naphthol UDP-glucuronosyl transferase were, however, well stabilized in 7-day-old co-cultures of parenchymal cells with two different lines of rat liver nonparenchymal epithelial cells (NEC1 and NEC2). Phenol sulfotransferase and microsomal epoxide hydrolase activity were reduced in this coculture system after 7 days to about 30 and 20% of …
Sulfītu noteikšana vīnā un augļu sulā ar eksprestestu metodi
2015
Sulfītjonu noteikšana vīnā un augļu sulās ar eksprestestu metodi. Muktupāvels A., darba vadītājs LU ĶF docents Ģībietis J. Bakalaura darbs, 35 lappuses, 14 attēli, 9 tabulas, 19 literatūras avoti, 3 pielikumi. Latviešu valodā. Darbā pētīta para-rosanalīna-formaldehīda spektrofotometriskās metodes izmantošana sulfītu noteikšanai vīnā un augļu sulās. Izstrādāta para-rosanalīna-formaldehīda ekspresmetode sulfītu kvantitatīvajai noteikšanai vīnā un augļu sulās, izmantojot teststrēmeles. Analizēts sulfītu daudzums vairākos vīna un augļu sulu paraugos. Iegūtie rezultāti salīdzināti ar rezultātiem, kas iegūti ar standartmetodi.
Directly probing the chirality of Majorana edge states
2021
We propose to directly probe the chirality of Majorana edge states in 2D topological superconductors using polarization selective photon absorption. When shining circularly polarized light on a 2D topological superconductor in disk geometry, the photons can excite quasiparticles only when the polarization of the light matches the chirality of the Majorana edge states required by the angular momentum conservation. Hence, one can obtain the chirality of the Majorana edge states by measuring the photon absorption rate. We show that the polarization selective photon absorption can also serve as smoking gun evidence of the chiral Majorana edge mode.
Meža cūku (Sus scrofa) līķu loma Āfrikas cūku mēra izplatībā: eksperiments dabā
2017
Darba mērķis ir noskaidrot, kādas sugas, cik bieži un daudz dabiskos apstākļos barojas ar meža cūku līķiem. Dzīvniekus fiksēja ar divām Spypoint 8MP Game Camera with Wireless Photo Trans up to 250 Feet un sešām Ltl Acorn 6210 MC automātiskajām dzīvnieku fotokamerām divos parauglaukumos – mežā ar kokiem aizklātā vietā un atklātā vietā meža ielokā. Pētījums veikts sadarbībā ar Vides risinājumu institūtu Cēsu novada Vaives pagastā. Darbā dati analizēti laika posmā no 2016. gada augusta līdz 2017. gada martam. Pēc fotokameru failu analizēšanas secināja, ka visbiežāk ar meža cūkas līķi barojās šādas sugas: krauklis, žagata, meža cūka un rudā lapsa. Novēroja, ka ar meža cūkas līķi barojās meža cū…
Direct assessment of the sensitivity drift of SQM sensors installed outdoors
2021
Long-term monitoring of the evolution of the artificial night sky brightness is a key tool for developing science-informed public policies and assessing the efficacy of light pollution mitigation measures. Detecting the underlying artificial brightness trend is a challenging task, since the typical night sky brightness signal shows a large variability with characteristic time scales ranging from seconds to years. In order to effectively isolate the weak signature of the effect of interest, determining the potential long term drifts of the radiance sensing systems is crucial. If these drifts can be adequately characterized, the raw measurements could be easily corrected for them and transfor…
Punktveida defektu īpašības bārija itrija fluorīda kristālā
2016
Darba ietvaros veikti punktveida defektu pētījumi BaY2F8 kristālā, izmantojot elektronu paramagnētiskās rezonanses (EPR) un optiskās spektroskopijas metodes. Ar optisko metožu palīdzību iegūti luminiscences spektri un noteikts, ka paraugs satur erbija, disprozija un praziodīma aktivatorus. Līdz šim BaY2F8 nav plaši pētīts ar magnētiskās rezonanses spektroskopijas metodēm un šajā darbā ir iegūts jauns rezultāts. Paraugam veiktajos EPR spektru leņķisko atkarību mērījumos istabas (295 K) un šķidrā slāpekļa (77 K) temperatūrās redzams liels līniju skaits plašā intervālā, kas liecina par gadolīnija jonu klātbūtni kristālā.
Educación patrimonial y fotografía estereoscópica: intervención didácti
2019
La inserción de la tecnología digital para el trabajo del patrimonio material e inmaterial puede convertirse en una herramienta creativa que refuerce el papel del maestro/a como agente educador del patrimonio local (en la línea de lo sugerido en el Plan Nacional de Educación y Patrimonio (PNEyP)). Además, este tipo de recursos permiten el desarrollo de herramientas que mejoran la interpretación de los entornos patrimoniales y los acercan al alumnado. En esta propuesta de innovación se expone una intervención didáctica original realizada con discentes de sexto de Educación Primaria en el entorno del Castell de Marinyén (Benifairó de la Valldigna, Valencia) por medio de la utilización de la f…
Termo- e foto- degradazione di nano compositi a base di nylon 11
2016
Negli ultimi anni la poliammide 11 (PA11) ha suscitato un notevole interesse in svariati settori industriali industriali.Per ottimizzare la comprensione dei meccanismi che governano la termo e foto ossidazione della PA11, sono stati studiati mediante Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) , cromatografia ad esclusione sterica (SEC) e viscosimetria, i processi di degradazione termo e foto-ossidativi che interessano il PA11 ed in particolare i nanocompositi formulati con Cloisite30B