Search results for "FOT"
showing 10 items of 1161 documents
Efficient Monolithic Perovskite/Perovskite Tandem Solar Cells
2016
Thin-film solar cells suffer from various types of recombination, of which leakage current usually dominates at lower voltages. Herein, we demonstrate first a three-order reduction of the shunt loss mechanism in planar methylammonium lead iodide perovskite solar cells by replacing the commonly used hole transport layer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with a better hole-selective polyarylamine. As a result, these cells exhibit superior operation under reduced light conditions, which we demonstrate for the extreme case of moonlight irradiance, at which open-circuit voltages of 530 mV can still be obtained. By the shunt removal we also observe the VOC to dro…
A newin vitroapproach for the simultaneous determination of phase I and phase II enzymatic activities of human hepatocyte preparations
2007
Primary hepatocytes are still the best qualified in vitro system to anticipate drug metabolism in man. Recent advances in hepatocytes cryopreservation have notably increased their use not only for drug metabolism studies, but also for other applications such as cell transplantation. Evaluation of the drug-metabolizing competence of each hepatocytes preparation is needed. To date, the metabolic characterization of hepatocytes preparations relies on the assessment of phase I activities and the role of phase II enzymes receives little attention. A novel approach for the rapid assessment of the metabolic functionality of hepatocytes has been developed. A five-probe cocktail was used to simultan…
Stable Expression of Heterologous Sulfotransferase in V79 Cells: Activation of Primary and Secondary Benzylic Alcohols
1994
Abstract A sulfotransferase (ST) capable of activating 1-hydroxymethylpyrene (HMP) and 9-hydroxymethylanthracene (HMA) to mutagens was purified from rat liver. This enzyme appeared to be identical with hydroxysteroid STa, whose cDNA was cloned and stably expressed in Chinese hamster V79 cells. Several primary and secondary benzylic alcohols derived from polycyclic aromatic hydrocarbons induced gene mutations, sister chromatid exchanges (SCE) and/or cytotoxicity in these cells.
Enzymic Control of Reactive Metabolites from Aromatic Carcinogens
1980
Mutation and transformation in C3H 10T 1/2 mouse fibroblasts were coordinately induced by 4-nitroquinoline N-oxide and identically modulated by caffeine strongly suggesting mutation as one necessary step in the sequence of events ultimately leading to transformation. The enzymic control of reactive metabolites derived from aromatic carcinogens was then investigated using bacterial mutagenicity as an analytical tool. It was shown that the correlation of bacterial mutagenicity with carcinogenicity of BP and four major metabolites was substantially better when these compounds were activated by intact hepatocytes as compared to commonly used broken cell preparations which suggests that the rela…
Strutture del “congelamento” nel cinema
2009
Jauna veida cinka oksīda/poliakrilnitrila nanokabeļu struktūras un optisko īpašību saistība
2015
Darbā tika pētīti jauna veida nanokabeļi, kuru apvalku veido cinka oksīda slānis, bet serdi poliakrilnitrils (ZnO/PAN). Paraugi tika izgatavoti apvienojot elektrovērpšanas un atomāru slāņu uzklāšanas (ASU) metodes, kas ļāva iegūt jaunu materiālu ar lielu virsmas/tilpuma attiecību. ZnO/PAN nanokabeļu struktūra tika pētīta ar rentgenstaru difrakcijas, skenējošās elektronu mikroskopijas, infrasarkanās Furjē spektroskopijas un transmisijas elektronu mikroskopijas metodēm. Tika pētīta nanokabeļu fotoluminiscences īpašību atkarība no ZnO slāņa biezuma robežās no 20 līdz 5 nm. Darbā tiks izskaidrotas paraugus raksturojošo parametru izmaiņas atkarībā no novērotajām jauna veida materiāla struktūras …
Sigma 1 receptora gēna izslēgšanas ietekme uz adipozo audu stromas šūnu diferenciāciju
2020
Cilmes šūnu iegūšanas avoti, diferenciācijas potenciāli un kas to ietekmē, un to izmantošana terapeitiskos nolūkos ir liels diskusiju un izpētes objekts. Viens no variantiem ir no taukaudiem iegūtās stromas šūnas, kuras ir multipotentas cilmes šūnas, kurām ir pierādīta spēja diferencēties pa osteogēno līniju, kā arī adipogēnu, hondrogēnu un miogēnu šūnu tipiem un citiem. Tiek apskatīti faktori, kas var ietekmēt to diferenciāciju. Šī darba mērķis bija gūt labāku ieskatu uz Sigma 1 receptora gēna izslēgšanas jeb inaktivēšanas ietekmi uz adipozo audu stromas šūnu diferenciāciju. Maģistra darba uzdevumi bija papildināt iemaņas darbā šūnu kultūru laboratorijā un apskatīt pieejamo literatūru par …
Pomelie e melanzane
2022
Il saggio descrive il progetto fotografico di Sandro Scalia, riletto anche attraverso una raccolta di immagini, affiancato da un apparato di didascalie e una scheda biografica, che hanno come soggetto la città e i suoi patrimoni. In Ascolto il tuo cuore, città, Alberto Savinio adopera un «lungo e tranquillo conversare», che è anche un «passeggiare» per le strade della sua Milano, in un movimento lento che sembra accordarsi all’incedere del passo e della narrazione. Pagina dopo pagina le parole, le frasi, i capitoli si vanno componendo, e con loro si vanno costruendo le immagini di quella «città tutta pietra in apparenza e dura», quanto «morbida di giardini “interni”» (Savinio, 1984). Nel ra…
METAPOLIS. La stasi della presenza nelle solitudini dello spazio
2018
Il saggio analizza il lavoro fotografico di Michele Di Donato “Metapolis” realizzato nei centri di Tratalias, Murano e Burano. L’analisi mette in evidenza la prospettiva antropologica adottata dall’artista. “Metapolis”, infatti, si presenta come un particolare racconto sulla solitudine dell’uomo contemporaneo attraverso una visione dello spazio urbano metafisico dove la quiete, la solitudine, l’indeterminatezza, l’assenza, sono condizioni che, in particolari momenti, magnetizzano certi luoghi investendoli di un senso altro e incomprensibile, di una figurazione misteriosa e onirica.