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The Influence of Titania Electrode Modification with Lanthanide Ions Containing Thin Layer on the Performance of Dye-Sensitized Solar Cells
PublikacjaThe lanthanide and scandium groups ions (except Pm and Ac) have been used as dopants of TiO2 film in dye-sensitized solar cells. The X-ray diffraction spectra show that the modification has no influence on the structure of the electrode; however, the diffuse reflectance UV-Vis measurements exhibit significant changes in the electronic properties of modified electrodes. The appearance of energy barrier preventing photoexcited electron...
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The imidazoacridinone C-1311 induces p53-dependent senescence or p53-independent apoptosis and sensitizes cancer cells to radiation
PublikacjaC-1311 is a small molecule, which has shown promise in a number of preclinical and clinical studies. However, the biological response to C-1311 exposure is complicated and has been reported to involve a number of cell fates. Here, we investigated the molecular signaling which determines the response to C-1311 in both cancer and non-cancer cell lines. For the first time we demonstrate that the tumor suppressor, p53 plays a key role...
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Chromatographic analyses of Lavandula angustifolia and Rosmarinus officinalis extracts and their biological effects in mammalian cells and cell-free systems
PublikacjaKnowledge of biological properties of natural compounds allows to understand their therapeutic value, efficacy and security. We investigated: composition of Lavandula angustifolia (LA) and Rosmarinus officinalis (RO) extracts, their antioxidant capacity, cytotoxicity and genotoxicity, their DNA-protective potential against DNA damage induced in hamster V79 cells by several genotoxins or in plasmid DNA by Fe2+ ions and activity...
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Design and experimental validation of a single-stage PV string inverter with optimal number of interleaved buck-boost cells.
PublikacjaIncreasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number...
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Synthetic lipopeptides as potential topical therapeutics in wound and skin care: in vitro studies of permeation and skin cells behaviour
PublikacjaSeveral Gly-His-Lys analogues were obtained to investigate their antimicrobial properties. Three lipophilic analogues with the structure numbering 1b, 2b, 4b, exhibit significant effect against bacteria and were selected for in vitro evaluation of skin cells behaviour. In the present studies, an in vitro model of wound repair, proliferative cell staining, and tracking of living cells were used. Cell proliferation and cell migration,...
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The importance of anchoring ligands of binuclear sensitizers on electron transfer processes and photovoltaic action in dye-sensitized solar cells
PublikacjaThe relatively low photon-to-current conversion efficiency of dye-sensitized solar cells is their major drawback limiting widespread application. Light harvesting, followed by a series of electron transfer processes, is the critical step in photocurrent generation. An in-depth understanding and fine optimization of those processes are crucial to enhance cell performance. In this work, we synthesize two new bi-ruthenium sensitizers...
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Improvement of Oxygen Electrode Performance of Intermediate Temperature Solid Oxide Cells by Spray Pyrolysis Deposited Active Layers
PublikacjaIntermediate temperature solid oxide fuel cells oxygen electrodes are modified by active interfacial layers. Spray pyrolysis is used to produce thin (≈500 nm) layers of mixed ionic and electronic conductors: Sm0.5Sr0.5CoO3−δ (SSC), La0.6Sr0.4CoO3−δ (LSC), La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF), and Pr6O11 (PrOx) on the electrode–electrolyte interface. The influence of the annealing temperature on the electrode polarization (area specific...
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Synthesis of Titanium Dioxide via Surfactant-Assisted Microwave Method for Photocatalytic and Dye-Sensitized Solar Cells Applications
PublikacjaIn this study, titania nanoparticles were obtained using the microwave-assisted technique. Moreover, different surfactants (PEG (Mn = 400), Pluronic P123 and Triton X−100) were used during the synthesis in order to determine their impact on the crystallinity and morphology of the final products. Subsequently, techniques such as XRD, SEM and TEM (performed in high contrast and high-resolution mode), diffuse reflectance spectroscopy...
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Investigating the Effects of Geometrical Parameters of Re-Entrant Cells of Aluminum 7075-T651 Auxetic Structures on Fatigue Life
PublikacjaIn this study, the effects of two geometrical parameters of the re-entrant auxetic cells, namely, internal cell angle (θ) and H/L ratio in which H is the cell height, and L is the cell length, have been studied on the variations of Poisson’s ratio and fatigue life of Aluminum 7075-T6 auxetic structures. Five different values of both the H/L ratio and angle θ were selected. Numerical simulations and fatigue life predictions have...
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Potent antitumor 4-methyl-1-nitroacridine C-1748 induces apoptosis only in part of colon cells
PublikacjaCelem przedstawionej pracy było zbadanie zdolności pochodnej 1-nitroakrydyny C-1748 do indukcji apoptozy komórek raka jelita grubego HCT8 i HT29 pochodzenia ludzkiego. Śmierć komórek była badana przez określony czas inkubacji komórek ze związkiem w stężeniach odpowiadających wartościom EC90 lub ich wielokrotnościom przez czas od 3 do 72 godzin. Uzyskane wyniki wskazują, że C-1748 indukuje apoptozę zależną od czasu tylko w części...
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Induction of G2/M phase arrest and apoptosis of human leukemia cells by potent antitumor triazoloacridinone C-1305
PublikacjaWykazaliśmy, że pochodna triazoloakrydonu C-1305 w stężeniach biologicznie istotnych indukuje blok cyklu komórkowego w fazie G2/M i apoptozę w komórkach białaczek ludzkich MOLT4 i HL60. Zjawisko apoptozy zostało określone na podstawie charakterystycznych zmian morfologicznych jak i biochemicznych tj. fragmentacji DNA, aktywacji kaspazy 3, cięcia PARP, spadku potencjału mitochondrialnego i ATP oraz eksternalizacji fosfatydyloseryny.
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Hydrolytic and transgalactosylation activities of immobilized Escherichia coli cells transformed by β-galactosidase gene from Pyrococcus woesei
PublikacjaPrzedstawiono wyniki badań dotyczących skuteczności transformacji laktozy katalizowanej immobilizowanymi w żelu alginianowym rekombinantowymi komórkami Escherichia coli, transformowanymi genem b-galaktozydazy z Pyrococcus woesei. Wykazano, że aktywność hydrolityczna rekombinantowych komórek wzrasta o 35% po permeabilizacji w środowisku 40% etanolu. Optymalna temperatura i pH katalizowanej reakcji wynosiły odpowiednio 98C i 5,4....
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S-seco-porphyrazine as a new member of the seco-porphyrazine family – Synthesis, characterization and photocytotoxicity against cancer cells
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Are Radiosensitive and Regular Response Cells Homogeneous in Their Correlations Between Copy Number State and Surviving Fraction After Irradiation?
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Mechanism of selective anticancer activity of isothiocyanates relies on differences in DNA damage repair between cancer and healthy cells
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CYP19 mRNA and protein levels in nontumorogenic breast epithelial cells (MCF10A) treated with active components of cabbage juices
PublikacjaZbadano wpływ soków z kapusty na poziom ekspresji genu CYP19 w nietumorogennych komórkach nabłonka gruczołu mlekowego MCF10A kodującego enzym aromatazę uczestniczący w biosyntezie estrogenów i w związku z tym wpływający na zagrożenie rakiem piersi. Soki z kapusty oraz bioaktywne związki w nich występujące stosowane w niskich dawkach obniżały poziom ekspresji tego genu, a zatem miały działanie chemoprewencyjne. Wyższe dawki zarowno...
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DNA structure and integrity checkpoints in the cell cycle and their role in drug targeting and resistance of tumor cells to anticancer treatment
PublikacjaW artykule dokonaliśmy przeglądu literatury dotyczącej różnych typów uszkodzeń DNA indukowanych przez różne czynniki terapeutyczne w komórkach nowotworowych. Omówiliśmy także w jaki sposób aktywują różne typy punktów kontrolnych w cyklu komórkowym i w jaki sposób punkty te są regulowane przez inne szlaki sygnalizacji wewnątrzkomórkowej takie jak szlaki naprawy uszkodzeń DNA, stresu komórkowego i śmierci-przeżycia. W szczególności...
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Metabolism of antitumor 9-amino-1-nitroacridine derivatives in HepG2 cells and its influence on cytochrome P450 isoenzymes
PublikacjaCelem przeprowadzonych badań było określenie wpływu pochodnych C-857 i C-1748 na poziom enzymów cytochromu P450 w powiązaniu z kinetyką metabolizmu badanych związków. Eksperymenty zostały przeprowadzone na komórkach ludzkiego nowotworu wątroby HepG2. Uzyskane wyniki metodą Western blotting wykazały, że za metaboliczną transformacje pochodnych C-857 i C-1748 odpowiada izoenzym CYP3A4.Analiza metabolitów (Western blotting, HPLC)...
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Bacteria Residing at Root Canals Can Induce Cell Proliferation and Alter the Mechanical Properties of Gingival and Cancer Cells
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Effective Targeting of Colon Cancer Cells with Piperine Natural Anticancer Prodrug Using Functionalized Clusters of Hydroxyapatite Nanoparticles
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Expression Profile of Genes Regulating Steroid Biosynthesis and Metabolism in Human Ovarian Granulosa Cells—A Primary Culture Approach
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Genes regulating biochemical pathways of oxygen metabolism in porcine oviductal epithelial cells during long-term IVC
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Potent antitumor 4-methyl-1-nitroacridine C-1748 induces apoptosis only in part of colon cells
PublikacjaZbadaliśmy zdolność pochodnej 4-metylo-1-nitroakrydyny C-1748 do indukcji apoptozy w ludzkich komórkach nowotworów jelita grubego HCT-8 i HT29 w stężeniach biologicznie istotnych. Zjawisko apoptozy określiliśmy na podstawie zmian morfologicznych jak i biochemicznych tj. fragmentacji DNA, aktywacji kaspazy-3, spadku potencjału mitochondrialnego, eksternalizacji fosfatydyloseryny i pojawiania się frakcji sub-G1. Wykazaliśmy, że pochodna...
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A freeze-thaw method for desintegration of Escherichia coli cells producing T7 lysozyme used in pBAD expression systems
PublikacjaPlazmid pLysN zawierający gen kodujący lizozym T7 pod kontrolą promotora lac został skonstruowany w celu ułatwienia dezintegracji komórek po ekspresji rekombinantowych białek w systemach ekspresji indukowanych arabinozą. Użyteczność plazmidu została przetestowana w komórkach Escherichia coli TOP10 i E. coli LMG194, niosących plazmid pBADMHADgeSSB, zawierający gen kodujący białko SSB Deinococcus geothermalis pod kontrolą promotora...
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The cellular response of human hepatoma cells with different expression of CYP3A4 isoenzyme to treatment with triazoloacridinone derivative C-1305
PublikacjaCelem badań było określenie w jaki sposób ekspresja enzymów odpowiedzialnych za metabolizm pochodnej triazoloakrydonu C-1305 wpływa na odpowiedź komórek ludzkiego raka wątroby HepG2 i Hep3A4. W komórkach HepG2 triazoloakrydon C-1305 indukuje proces starzenia, podczas gdy w przypadku linii Hep3A4, komórki ulegają apoptozie oraz nekrozie.
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Co-free triple perovskite La1.5Ba1.5Cu3O7±δ as a promising air electrode material for solid oxide fuel cells
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Neutrophilic Cathepsin C Is Maturated by a Multistep Proteolytic Process and Secreted by Activated Cells during Inflammatory Lung Diseases
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Application of specific cell permeable cathepsin G inhibitors resulted in reduced antigen processing in primary dendritic cells
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Trends in biomedical analysis of red blood cells – Raman spectroscopy against other spectroscopic, microscopic and classical techniques
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Modulatory Effects of Curcumin and Tyrphostins (AG494 and AG1478) on Growth Regulation and Viability of LN229 Human Brain Cancer Cells
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Morphological and cellular alternations of HepG2 cells overexpressing CYP3A4 after treatment with antitumor imidazoacridinone derivative C-1311
PublikacjaW pracy badano odpowiedź biologiczną komórek nowotworu wątroby HepG2 z nadekspresją izoenzymu CYP3A4 pod wpływem pochodnej imidazoakrydonu C-1311. Wyniki porównywano z odpowiedzią komórek HepG2 z tzw. wektorem zerowym.Izoeznym CYP3A4 jest jednym z izoenzymów cytochromu P450 odpowiedzialnych za przemiany metaboliczne pochodnej C-1311. Wykazano, że pochodna C-1311 indukuje w obu liniach komórkowych blok w fazie G2/M cyklu komórkowego,...
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Role of adenylate kinase 4 as a new metabolic regulator of pulmonary artery smooth muscle cells under hypoxia
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Development of Safirinium dyes for new applications: fluorescent staining of bacteria, human kidney cells, and the horny layer of the epidermis
PublikacjaLow-molecular synthetic fluorophores are convenient tools in bioimaging applications. Several derivatives of Safirinium dyes as well as their reactive N-hydroxysuccinimide (NHS) esters bearing diverse substituents were synthesized and evaluated experimentally in terms of their lipophilicity by means of reverse-phase and immobilized artificial membrane high-performance liquid chromatography. Subsequently, the selected compounds...
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The influence of dynamic load changes on temporary impedance in hydrogen fuel cells, selection and validation of the electrical equivalent circuit
PublikacjaTo achieve optimal performance of a fuel cell, a reliable monitoring and diagnostic method is required. The currently utilized methods give limited information or they are impossible to use under dynamic working conditions. To obtain comprehensive information about the fuel cell operation we utilized novel dynamic electrochemical impedance spectroscopy. Impedance measurements in dynamic mode were performed on a hydrogen fuel cell,...
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Effective yttrium based coating for steel interconnects of solid oxide cells: Corrosion evaluation in steam-hydrogen atmosphere
PublikacjaThis work describes manufacture, analysis and test of a new well conducting corrosion-protection coating that can be applied on steel types with high chromium content. Electrolytic deposition of yttrium salts is used to form thin (<100 nm) coatings on both flat steel sheets (material: Crofer 22 APU) and its properties are proven on woven wire-meshes (materials from two different sources: SUS316 and SUS316L). The oxide scale on...
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Quantum Dots as a Good Carriers of Unsymmetrical Bisacridines for Modulating Cellular Uptake and the Biological Response in Lung and Colon Cancer Cells
PublikacjaNanotechnology-based drug delivery provides a promising area for improving the efficacy of cancer treatments. Therefore, we investigate the potential of using quantum dots (QDs) as drug carriers for antitumor unsymmetrical bisacridine derivatives (UAs) to cancer cells. We examine the influence of QD–UA hybrids on the cellular uptake, internalization (Confocal Laser Scanning Microscope), and the biological response (flow cytometry...
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Targeting of FLT3-ITD kinase contributes to high selectivity of imidazoacridinone C-1311 against FLT3-activated leukemia cells
PublikacjaDrugs targeting receptor tyrosine kinase FLT3 are of particular interest since activating FLT3-internal tandem duplication (ITD) mutations abundantly occur in fatal acute myeloid leukemias (AMLs). Imidazoacridinone C-1311, a DNA-reactive inhibitor of topoisomerase II, has been previously shown to be a potent and selective inhibitor of recombinant FLT3. Here, we expand those findings by studying its effect on leukemia cells with...
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The impact of air humidity on the operation of proton exchange membrane fuel cells determined using dynamic electrochemical impedance spectroscopy
PublikacjaThis paper describes the changes in the fuel cell impedance across a range of current loads and humidity changes. The changes of each equivalent circuit parameters representing specific processes occurring in fuel cells, as a function of humidity and current changes, were determined. Within the combined scope of current and humidity, the optimal working conditions of the cells were determined, corresponding to the lowest impedance...
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Foliate-Targeting Quantum Dots-β-Cyclodextrin Nanocarrier for Efficient Delivery of Unsymmetrical Bisacridines to Lung and Prostate Cancer Cells
PublikacjaTargeted drug delivery by nanocarriers molecules can increase the efficiency of cancer treatment. One of the targeting ligands is folic acid (FA), which has a high affinity for the folic acid receptors, which are overexpressed in many cancers. Herein, we describe the preparation of the nanoconjugates containing quantum dots (QDs) and β-cyclodextrin (β-CD) with foliate-targeting properties for the delivery of anticancer compound...
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Processing of Ce0.8Gd0.2O2-δ barrier layers for solid oxide cells: The effect of preparation method and thickness on the interdiffusion and electrochemical performance
PublikacjaCe0.8Gd0.2O1.9 (CGO) barrier layers are required to mitigate the chemical reactions between Sr-containing oxygen electrode materials and Zr-based oxygen ion conductors in high-temperature solid oxide cells. Barrier layers produced by different methods were studied in this work. As a reference, a cell with no barrier layer was measured. The application of the powder-processed barrier layers, considerably increases the performance....
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Characteristics of La0.8Sr0.2Ga0.8Mg0.2O3-delta -supported micro-tubular solid oxide fuel cells with bi-layer and tri-layer electrolytes
PublikacjaIn this study, La0.8Sr0.2Ga0.8Mg0.2O3−δ (LSGM)-supported micro tubular solid oxide fuel cells (T-SOFCs) with two different configurations, one containing an LSGM–Ce0.6La0.4O2−δ (LDC) bi-layer electrolyte (Cell A) and one containing an LDC–LSGM–LDC tri-layer electrolyte (Cell B), were fabricated using extrusion and dip-coating. After optimizing the paste formulation for extrusion, the flexural strength of the dense and uniform LSGM...
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Influence of temperature and nitrogen pressure on the test without active gases for high-temperature proton exchange membrane fuel cells
PublikacjaHigh-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) are a candidate for electrical energy supply devices in more and more applications. Most notably in the aeronautic industry. Before any use, an HT-PEMFC is preheated and after that supplied with its active gases. Only at this state, the diagnostics can be performed. A method of testing not requiring a complete start-up would be beneficial for many reasons. This article...
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CGO as a barrier layer between LSCF electrodes and YSZ electrolyte fabricated by spray pyrolysis for solid oxide fuel cells
PublikacjaPerovskite La0.6Sr0.4Co0.2Fe0.8O3 − δ (LSCF) is often used as a cathode material for solid oxide fuel cells (SOFC) due to high mixed ionic and electronic conductivity and good catalytic activity. Unfortunately, sintering of the LSCF cathode together with the yttria stabilized zirconia (YSZ) electrolyte, leads to formation of the La2Zr2O7 and SrZrO3 phases in the interface. These phases increase the resistance of the cell. To avoid...
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Investigation of thin perovskite layers between cathode and doped ceria used as buffer layer in solid oxide fuel cells
PublikacjaIn this paper, thin perovskite layers between cathode material of solid oxide fuel cells and gadolinia-doped ceria buffer layer are investigated. Thin layers made of LaNi0.6Fe0.4O3-δ (LNF), La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), or SrTi0.65Fe0.35O3-δ (STF) were symmetrically deposited by spin coating method from metallo-organic polymer precursors on a Ce0.8Gd0.2O2-δ (CGO) substrate. Porous and about 40-μm-thick LNF cathodes were deposited...
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High performance LaNi1-xCoxO3-δ (x = 0.4 to 0.7) infiltrated oxygen electrodes for reversible solid oxide cells
PublikacjaOxygen electrodes prepared by infiltration of yttria stabilized zirconia backbone with Ce0.8Gd0.2O1.95 barrier layer and LaNi1-xCoxO3-δ (x=0.4 to 0.7) catalyst for application in reversible solid oxide cells have been studied. The effect of temperature and Ni:Co ratio on their phase composition, microstructure and electrochemical properties are discussed. It was shown that oxygen electrodes infiltrated with LaNi0.5Co0.5O3-δ had...
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Effects of thermal history on the performance of low-temperature solid oxide fuel cells with Sm0.2Ce0.8O2-δ electrolyte and LiNi0.81Co0.15Al0.04O2 electrodes
PublikacjaIn this study, low-temperature solid oxide fuel cells with an ∼560 μm thick Sm0.2Ce0.8O2−δ (SDC) electrolyte and ∼890 μm thick LiNi0.81Co0.15Al0.04O2−δ (NCAL) electrodes are constructed and characterized under three experimental conditions. The cell with an NCAL cathode pre-reduced under an H2 atmosphere at 550 °C presents the best electrochemical performance. This is ascribed to facts that the reduction reaction generating Ni–Co...
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High-performance NdSrCo2O5+δ–Ce0.8Gd0.2O2-δ composite cathodes for electrolyte-supported microtubular solid oxide fuel cells
PublikacjaNdSrCo2O5+δ (NSCO) is a perovskite with an electrical conductivity of 1551.3 S cm−1 at 500 °C and 921.7 S cm−1 at 800 °C and has a metal-like temperature dependence. This perovskite is used as the cathode material for Ce0.8Gd0.2O2-δ (GDC)-supported microtubular solid oxide fuel cells (MT-SOFCs). The MT-SOFCs fabricated in this study consist of a bilayer anode, comprising a NiO–GDC composite layer and a NiO layer, and a NSCO–GDC...
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Human Adipose-Derived and Amniotic Fluid-Derived Stem Cells: A Preliminary In Vitro Study Comparing Myogenic Differentiation Capability
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Structure modification of acridine antitumor agents results in changes of enzymatic activity and gene expression of CYP3A4 isoenzyme in HepG2 cells.
PublikacjaEkspresja izoenzymu CYP3A4, który zaangażowany jest w metabolizm ok. 60% leków stosowanych klinicznie, może być modulowana przez takie czynniki jak: polimorfizm, czynniki transkrypcyjne oraz obecność ksenobiotyków. Przykładem induktorów genów kodujących izoenzym CYP3A4 jest fenobarbital i rifampicyna, których obecność w organizmie przyspiesza metabolizm innych leków stosowanych jednocześnie, które są substratami dla CYP3A4. Dlatego...
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Ti-doped Sr2Fe1.4-xTixMo0.6O6-δ double perovskites with improved stability as anode materials for Solid Oxide Fuel Cells
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