8 research outputs found

    Anti-corrosive siloxane coatings for improved long-term performance of supercapacitors with an aqueous electrolyte

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    This paper reports on the impact that the corrosion of the stainless steel current collectors has on the performance fade of a symmetric, carbon/carbon electrochemical capacitor, operating with an aqueous electrolyte (1M Na2SO4). The results obtained by applying electrochemical ageing protocols (voltage-holding tests) confirm that the current collector of the positive electrode undergoes tremendous degradation during 200 h in the charged state. To prevent the detrimental impact of the corrosion, a hydrophobic siloxane coating has been successfully applied. In the case of siloxane-protected current collectors that are subjected to identical ageing protocols, no significant deterioration in the electrochemical capacitor performance was observed. The siloxane coating reduces the electrochemical corrosion rate of 316L stainless steel significantly, as the potentiodynamic polarization tests and the electrochemical impedance spectroscopy results show. The presence of the coating is demonstrated by the water contact angle measurements, atomic force microscopy and energy-dispersive X-ray spectroscopy analysis

    Carbon Fiber and Nickel Coated Carbon Fiber–Silica Aerogel Nanocomposite as Low-Frequency Microwave Absorbing Materials

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    Silica aerogel-based materials exhibit a great potential for application in many industrial applications due to their unique porous structure. In the framework of this study, carbon fiber and nickel coated carbon fiber–silica aerogel nanocomposites were proposed as effective electromagnetic shielding material. Herein, the initial oxidation of the surface of carbon fibers allowed the deposition of a durable Ni metallic nanolayer. The fibers prepared in this way were then introduced into a silica aerogel structure, which resulted in obtaining two nanocomposites that differed in terms of fiber volume content (10% and 15%). In addition, analogous systems containing fibers without a metallic nanolayer were studied. The conducted research indicated that carbon fibers with a Ni nanolayer present in the silica aerogel structure negatively affected the structural properties of the composite, but were characterized by two-times higher electrical conductivity of the composite. This was because the nickel nanolayer effectively blocked the binding of the fiber surface to the silica skeleton, which resulted in an increase of the density of the composite and a reduction in the specific surface area. The thermal stability of the material also deteriorated. Nevertheless, a very high electromagnetic radiation absorption capacity between 40 and 56 dB in the frequency range from 8 to 18 GHz was obtained

    Multiparametric Evaluation of Post-MI Small Animal Models Using Metabolic ([18F]FDG) and Perfusion-Based (SYN1) Heart Viability Tracers

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    Cardiovascular diseases (CVD), with myocardial infarction (MI) being one of the crucial components, wreak havoc in developed countries. Advanced imaging technologies are required to obtain quick and widely available diagnostic data. This paper describes a multimodal approach to in vivo perfusion imaging using the novel SYN1 tracer based on the fluorine-18 isotope. The NOD-SCID mice were injected intravenously with SYN1 or [18F] fluorodeoxyglucose ([18F]-FDG) radiotracers after induction of the MI. In all studies, the positron emission tomography–computed tomography (PET/CT) technique was used. To obtain hemodynamic data, mice were subjected to magnetic resonance imaging (MRI). Finally, the biodistribution of the SYN1 compound was performed using Wistar rat model. SYN1 showed normal accumulation in mouse and rat hearts, and MI hearts correctly indicated impaired cardiac segments when compared to [18F]-FDG uptake. In vivo PET/CT and MRI studies showed statistical convergence in terms of the size of the necrotic zone and cardiac function. This was further supported with RNAseq molecular analyses to correlate the candidate function genes’ expression, with Serpinb1c, Tnc and Nupr1, with Trem2 and Aldolase B functional correlations showing statistical significance in both SYN1 and [18F]-FDG. Our manuscript presents a new fluorine-18-based perfusion radiotracer for PET/CT imaging that may have importance in clinical applications. Future research should focus on confirmation of the data elucidated here to prepare SYN1 for first-in-human trials

    Molecular Imaging of Human Skeletal Myoblasts (huSKM) in Mouse Post-Infarction Myocardium

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    Current treatment protocols for myocardial infarction improve the outcome of disease to some extent but do not provide the clue for full regeneration of the heart tissues. An increasing body of evidence has shown that transplantation of cells may lead to some organ recovery. However, the optimal stem cell population has not been yet identified. We would like to propose a novel pro-regenerative treatment for post-infarction heart based on the combination of human skeletal myoblasts (huSkM) and mesenchymal stem cells (MSCs). huSkM native or overexpressing gene coding for Cx43 (huSKMCx43) alone or combined with MSCs were delivered in four cellular therapeutic variants into the healthy and post-infarction heart of mice while using molecular reporter probes. Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) performed right after cell delivery and 24 h later revealed a trend towards an increase in the isotopic uptake in the post-infarction group of animals treated by a combination of huSkMCx43 with MSC. Bioluminescent imaging (BLI) showed the highest increase in firefly luciferase (fluc) signal intensity in post-infarction heart treated with combination of huSkM and MSCs vs. huSkM alone (p < 0.0001). In healthy myocardium, however, nanoluciferase signal (nanoluc) intensity varied markedly between animals treated with stem cell populations either alone or in combinations with the tendency to be simply decreased. Therefore, our observations seem to show that MSCs supported viability, engraftment, and even proliferation of huSkM in the post-infarction heart

    Supplementary_table - The impact of in vitro cell culture duration on the maturation of human cardiomyocytes derived from induced pluripotent stem cells of myogenic origin

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    <p>Supplementary_table for The impact of in vitro cell culture duration on the maturation of human cardiomyocytes derived from induced pluripotent stem cells of myogenic origin by Jarosław Lewandowski, Natalia Rozwadowska, Tomasz J Kolanowski, Agnieszka Malcher, Agnieszka Zimna, Anna Rugowska, Katarzyna Fiedorowicz, Wojciech Łabędź, Łukasz Kubaszewski, Katarzyna Chojnacka, Katarzyna Bednarek-Rajewska, Przemysław Majewski, and Maciej Kurpisz in Cell Transplantation</p

    Supplementary_Material - The impact of in vitro cell culture duration on the maturation of human cardiomyocytes derived from induced pluripotent stem cells of myogenic origin

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    <p>Supplementary_Material for The impact of in vitro cell culture duration on the maturation of human cardiomyocytes derived from induced pluripotent stem cells of myogenic origin by Jarosław Lewandowski, Natalia Rozwadowska, Tomasz J Kolanowski, Agnieszka Malcher, Agnieszka Zimna, Anna Rugowska, Katarzyna Fiedorowicz, Wojciech Łabędź, Łukasz Kubaszewski, Katarzyna Chojnacka, Katarzyna Bednarek-Rajewska, Przemysław Majewski, and Maciej Kurpisz in Cell Transplantation</p
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