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This paper seeks to examine how the Mn–Co spinel interconnect coating microstructure can influence Cr contamination in an oxygen electrode of intermediate temperature solid oxide cells, at an operating temperature of 750 °C. A Mn–Co spinel coating is processed on Crofer 22 APU substrates by electrophoretic deposition, and subsequently sintered, following both the one-step and two-step sintering, in order to obtain significantly different densification levels. The electrochemical characterization is performed on anode-supported cells with an LSCF cathode. The cells were aged prior to the electrochemical characterization in contact with the spinel-coated Crofer 22 APU at 750 °C for 250 h. Current–voltage and impedance spectra of the cells were measured after the exposure with the interconnect. Post-mortem analysis of the interconnect and the cell was carried out, in order to assess the Cr retention capability of coatings with different microstructures.

This study presents the use of matrix-assisted laser desorption and ionization mass spectrometry imaging (MALDI-MSI) directly on the tissue of two ovarian tumors that often present a diagnostic challenge, a low-grade serous borderline ovarian tumor and ovarian fibrothecoma. Different spatial distribution of m/z values within the tissue samples was observed, and regiospecific peaks were identified. Among the 106 peaks in the borderline ovarian tumor five, regiospecific peaks (m/z: 2861.35, 2775.79, 3368.34, 3438.43, 4936.37) were selected using FlexImaging software. Subsequently, the distribution of those selected peaks was visualized on the fibrothecoma tissue section, which demonstrated the differences in the tissue homo-/heterogeneous structure of both tumors. The comparison with the histopathological staining of the ovarian borderline tumor tissue section, obtained during serial sectioning, showed a close correlation of the molecular map with the morphological and histopathological features of the tissue and allowed the identification of different tissue types within the sample. This study highlights the potential significance of MSI in enabling morphological characterization of ovarian tumors as well as correct diagnosis and further prognosis than thus far seen in the literature. Osteopontin, tropomyosin and orosomucoid are only a couple of the molecules investigated using MALDI-MSI in ovarian cancer research. This study, in line with the available literature, proves the potential of MALDI-MSI to overcome the current limitations of classic histopathological examination giving a more in-depth insight into the tissue structure and thus lead to the more accurate differential diagnosis of ovarian tumors, especially in the most challenging cases.

Ovarian cancer is the eighth most common cancer and the seventh highest cause of cancer-associated mortality in women worldwide. It is the second highest cause of mortality among female reproductive malignancies. The current standard first-line treatment for advanced ovarian cancer includes a combination of surgical debulking and standard systemic platinum-based chemotherapy with carboplatin and paclitaxel. Although a deeper understanding of this disease has been attained, relapse occurs in 70% of patients 18 months subsequent to the first-line treatment. Therefore, it is crucial to develop a novel drug that effectively affects ovarian cancer, particularly tumors that are resistant to current chemotherapy. The aim of the present study was to identify genes whose expression may be used to predict survival time or prognosis in ovarian cancer patients treated with chemotherapy. Gene or protein expression is an important issue in chemoresistance and survival prediction in ovarian cancer. In the present study, the research group consisted of patients treated at the Surgical Clinic of the Gynecology and Obstetrics Gynecological Clinical Hospital, Poznan University of Medical Sciences (Poznan, Poland) between May 2006 and November 2014. Additional eligibility criteria were a similar severity (International Federation of Gynecolgy and Obstetrics stage III) at the time of diagnosis, treatment undertaken in accordance with the same schedule, and an extremely good response to treatment or a lack of response to treatment. The performance of the OncoScan® assay was evaluated by running the assay on samples obtained from the four patients and by following the recommended protocol outlined in the OncoScan assay manual. The genomic screening using Affymetrix OncoScan Arrays resulted in the identification of large genomic rearrangements across all cancer tissues. In general, chromosome number changes were detected in all examined tissues. The OncoScan arrays enabled the identification of ~100 common somatic mutations. Chemotherapy response in ovarian cancer is extremely complex and challenging to study. The present study identified specific genetic alterations associated with ovarian cancer, but not with response for treatment.

Low-temperature deposition of electroceramic thin films allows the construction of new devices and their integration with existing large-scale fabrication methods. Developing a suitable low-cost deposition method is important to further advance the development of microdevices. In this work, we deposited a 1-μm-thick La0.6Sr0.4CoO3−δ (LSC) perovskite with high electrical conductivity on sapphire substrates at 400°C and analyzed its electrical, morphological and structural properties as a function of temperature in the range of 400–1100°C. The results show that spray pyrolysis can be used to deposit high-quality reproducible layers with the desired chemical and phase composition. Upon heating to around 600°C, the residual C–O and C=O species are removed, and the deposited layers crystallize and become conducting. The dependence of electrical conductivity versus processing temperature has a complex character—the maximum conductivity is found for layers processed at 800°C. An analytical model of stress distribution was used to predict stress to which the bi-layer material would be exposed to while being cooled down from the annealing temperature to room temperature. The high electronic conductivity and high-quality microstructure of the LSC layers, which can be adjusted with the appropriate heat treatment procedure, make them suitable for applications in electrochemical devices applied in integrated energy modules, including electrodes or contacts.

In this work, the potentiostatic electropolymerization of polypyrrole (PPy) on iron in aqueous solution of sodium salicylate and pyrrole is studied in situ by odd random phase electrochemical impedance spectroscopy (ORP-EIS). The influence of the pyrrole concentration on the electrosynthesis process is investigated. The ORP-EIS technique ensures a reliable analysis of the PPy electrosynthesis on iron by means of an advanced data analysis of the non-linear and non-stationary behaviour and the signal-to-noise ratio of the system. Additionally, the structure and the chemical nature of the PPy film on iron are studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and glow discharge optical emission spectroscopy (GDOES). The results of the characterization confirm the presence of the passivation layer at the PPy/iron interface formed prior to the polymer deposition. The modelling of the impedance evolution over time provides the quantitative analysis of the electropolymerization of PPy on iron. The results show that the electrosynthesis of pyrrole on oxidizable iron in the presence of sodium salicylate is a complex process, which includes not only the pyrrole oxidation reactions but also reactions such as the oxidation/reduction of the iron surface and/or reactions between the iron, formed interlayer and polypyrrole.

In this work, thin films (~1000 nm) of a pure MnCo2O4 spinel together with its partially substituted derivatives (MnCo1.6Cu0.2Fe0.2O4, MnCo1.6Cu0.4O4, MnCo1.6Fe0.4O4) were prepared by spray pyrolysis and were evaluated for electrical conductivity. Doping by Cu increases the electrical conductivity, whereas doping by Fe decreases the conductivity. For Cu containing samples, rapid grain growth occurs and these samples develop cracks due to a potentially too high thermal expansion coefficient mismatch to the support. Samples doped with both Cu and Fe show high electrical conductivity, normal grain growth and no cracks. By co-doping the Mn, Co spinel with both Cu and Fe, its properties can be tailored to reach a desired thermal expansion coefficient/electrical conductivity value.

In this work, electrochemical activity and electrical properties of polypyrrole (PPy) coated iron electrodes have been investigated. PPy film was electrochemically polymerized from sodium salicylate aqueous solution under conditions, which provided an increase of iron corrosion resistance. It was noticed that the pH of the solution and the applied electrode potential range during the study of the polymer properties had an influence on the observed electroactivity of PPy. The electroactivity of PPy was retained in neutral solution when the potential was scanned between −0.6 and 0.3 V. Also the resistance behavior of the synthesized polymer film as a function of the electrode potential during doping/dedoping processes was studied. Determination of the resistance was based on the impedance spectroscopy measurements and was performed in air, in order to avoid the influence of the solution resistance on the resistance of the studied polymer. Depending on the redox properties, the pH of solution and the potential range, different resistances of the polymer film during the doping/dedoping process can be obtained.

Iron doped strontium titanates SrTi 1-x Fe x O 3-δ are perovskites of versatile properties. They can be used in solid oxide fuel cells or high temperature oxygen sensors. Their reactivity with electrolyte materials, cathode buffer layer materials, other cathode materials or current collector layers has not been fully tested. In this study we use X-ray diffraction to check SrTi 0.65 Fe 0.35 O 3-δ compatibility with Ce 0.8 Gd 0.2 O 2-δ (used as electrolyte or cathode-YSZ electrolyte buffer layer), LaNi 0.6 Fe 0.4 O 3-δ (typical current collector) and La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (typical cathode). It is shown that SrTi 0.65 Fe 0.35 O 3-δ reactivity with Ce 0.8 Gd 0.2 O 2-δ and La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ is negligible up to 1400°C, while reaction with LaNi 0.6 Fe 0.4 O 3-δ occurs between 1000°C and 1200°C leading to the formation of NiO, SrLaFaO 4 and possibly La 4 Ni 3 O 10 .

Principle of operation of electrocatalytic gas sensors is based on the excitation of a sensor with a periodic potential signal, while current response is recorded. Usually such sensors employ cyclic voltammetry, where linearly changing voltage excitation of symmetrical triangular shape, typically in range of ±5V, is used. In this work we present results of electrocatalytic sensors employing staircase cyclic voltammetry technique. Presented results concern sensors based on Nasicon with platinum electrodes. It is demonstrated that such sensor can be used for measuring NO2 concentration in mixtures with synthetic air.

Stainless steels can be used in solid oxide fuel/electrolysis stacks as interconnects. For successful long term operation they require protective coatings, that lower the corrosion rate and block chemical reactions between the interconnect and adjacent layers of the oxygen or the hydrogen electrode. One of the promising coating materials for the hydrogen side is ceria. Using standard sintering techniques, ceria sinters at around 1400°C which even for a very short exposure would destroy the interconnect. Therefore in this paper a low temperature deposition method, i.e. spray pyrolysis, is used to deposit thin (∼400nm), continuous CeO2 layers on Crofer 22 APU steel substrates. Influence of the deposition parameters on layer quality is elucidated in this work.