Gelatin-pretreated carbon particles for potential use in lithium ion batteries

Graphite anodes for use in lithium ion batteries were prepared from graphite particles pretreated in a gelatin solution. The content of gelatin in the final anode material was determined from the difference in mass of graphite particles before and after the treatment with gelatin and by thermogravimetric analysis. Forces between a gelatin-coated glass particle and graphite surface were measured in solution using an atomic force microscope. The effect of gelatin content on the characteristics of first charge-discharge cycle is measured and commented in terms of a simple passivation model.     

Analysis of miR-9-5p,miR-124-3p,miR-21-5p,miR-138-5p,and miR-1-3p in Glioblastoma Cell Lines and Extracellular Vesicles

Glioblastoma (GBM), the most common primary brain tumor, is a complex and extremely aggressive disease. Despite recent advances in molecular biology, there is a lack of biomarkers, which would improve GBM’s diagnosis, prognosis, and therapy. Here, we analyzed by qPCR the expression levels of a set of miRNAs in GBM and lower-grade glioma human tissue samples and performed a survival analysis in silico. We then determined the expression of same miRNAs and their selected target mRNAs in small extracellular vesicles (sEVs) of GBM cell lines. We showed that the expression of miR-21-5p was significantly increased in GBM tissue compared to lower-grade glioma and reference brain tissue, while miR-124-3p and miR-138-5p were overexpressed in reference brain tissue compared to GBM. We also demonstrated that miR-9-5p and miR-124-3p were overexpressed in the sEVs of GBM stem cell lines (NCH421k or NCH644, respectively) compared to the sEVs of all other GBM cell lines and astrocytes. VIM mRNA, a target of miR-124-3p and miR-138-5p, was overexpressed in the sEVs of U251 and U87 GBM cell lines compared to the sEVs of GBM stem cell line and also astrocytes. Our results suggest VIM mRNA, miR-9-5p miRNA, and miR-124-3p miRNA could serve as biomarkers of the sEVs of GBM cells.     

Influence of carbon black distribution on performance of oxide cathodes for Li ion batteries

The influence of carbon black content and carbon black distribution on performance of oxide-based cathodes, such as LiCoO₂ and LiMn₂O₄, is investigated. The electronic conductivity of oxide material/carbon black composites is compared with electrochemical characteristics of the same composites. Uniformity of carbon black distribution in cathode composites is achieved using novel coating technology in cathode preparation. In this technology, the active particles are first pretreated in a gelatin solution. The adsorbed gelatin then controls the deposition of carbon black so that carbon black particles are uniformly distributed in the final composite. The influence of various parameters, such as pH of gelatin, amount of gelatin and concentration of carbon black on the uniformity of carbon black distribution is investigated. It is shown that the conventional technology of cathode preparation yields quite non-uniform distribution of carbon black in cathode material. At the end, we demonstrate that uniformity of carbon black distribution has a crucial impact on reversible capacity, especially at high current densities.     

Initial Morphology and Grain Growth in Donor-Doped Barium Titanate

The influence of the initial grain morphology on the anomalous grain growth in donor-doped barium titanate has been studied. The results show that powders with aspherically shaped grains exhibit a much lower critical donor-dopant concentration, inhibiting anomalous grain growth during sintering, than powders with equisized spherically shaped grains and a similar, or even a lower, initial specific surface area.     

Microstructural Changes during the Reduction/Reoxidation Process in Donor-Doped BaTiO3 Ceramics

Microstructural changes occurring during oxidation of the reduced form of donor-doped BaTiO₃ (Ba_{1− X} D _X ^.Ti_{1− X} ⁴⁺Ti _X ³⁺O₃) and during reduction of the oxidized form of donor-doped BaTiO₃ (Ba_{1− X} D _X ^.Ti_{1− X /4}⁴⁺( V _Ti^) _{X /4}O₃) were studied using TEM. Samples of both types of solid solutions, containing different La concentrations (from 2 to 20 mol% La), were prepared by sintering under reducing conditions and in air, respectively. The reduced form of donor-doped BaTiO₃ was oxidized by annealing at high temperatures (1150° and 1350°C) in air, while the oxidized form was reduced by annealing under reducing conditions. Because of oxidation of the reduced phase of donor-doped BaTiO₃, the Ti-rich phases Ba₆Ti₁₇O₄₀ and BaLa₂Ti₄O₁₂ were precipitated. Reduction of the oxidized form caused precipitation of the Ba-rich phase Ba₂TiO₄ preferentially inside the matrix grains. All precipitates had well-defined orientational relationships with the perovskite matrix.     

Thermal Treatment Influence on the Magnetic Properties and Degree of Orientation of BaFe12O19 Films

The process of preparation of oriented BaFe₁₂O₁₉ films with deposition of BaFe₁₂O₁₉ nanoparticles from 1-butanol suspension in a magnetic field was studied. The structural, microstructural, and magnetic properties were investigated by X-ray diffraction, scanning electronic microscopy, and magnetic measurements and the annealing conditions influence on the films?? orientations and microstructures was explored. The best BaFe₁₂O₁₉ film properties, saturation magnetization of 49?emu?g^?1, high values of coercive field (4.4?kOe), and squareness ratio of 0.92, were obtained on well-crystallized oriented BaFe₁₂O₁₉ films annealed at 1050?°C for 30?h.     

Astrocytic Vesicle Mobility in Health and Disease

Astrocytes are no longer considered subservient to neurons, and are, instead, now understood to play an active role in brain signaling. The intercellular communication of astrocytes with neurons and other non-neuronal cells involves the exchange of molecules by exocytotic and endocytotic processes through the trafficking of intracellular vesicles. Recent studies of single vesicle mobility in astrocytes have prompted new views of how astrocytes contribute to information processing in nervous tissue. Here, we review the trafficking of several types of membrane-bound vesicles that are specifically involved in the processes of (i) intercellular communication by gliotransmitters (glutamate, adenosine 5′-triphosphate, atrial natriuretic peptide), (ii) plasma membrane exchange of transporters and receptors (EAAT2, MHC-II), and (iii) the involvement of vesicle mobility carrying aquaporins (AQP4) in water homeostasis. The properties of vesicle traffic in astrocytes are discussed in respect to networking with neighboring cells in physiologic and pathologic conditions, such as amyotrophic lateral sclerosis, multiple sclerosis, and states in which astrocytes contribute to neuroinflammatory conditions.     

Sleeping beauties in health informatics research

Scientometrics - Scientific publications are received by the research community in various ways. Some articles are quickly cited, while others are discovered only after a longer period of time. The...     

Hexaferrite/Polyester Composite Coatings for Electromagnetic-Wave Absorbers

Composite coatings, consisting of a ceramic barium hexaferrite and polyester, were manufactured by atmospheric plasma spraying. The crystalline structure of the barium hexaferrite was preserved during the spraying process while the polyester first (partly) melted and then resolidified. The high magnetic losses of the barium hexaferrite at mm-waves were coupled to the dielectric losses of the polyester in the composite coating and the superior electromagnetic absorption of the composite coating with respect to the pure materials was determined.     

Preparation of Silica-Coated Lanthanum–Strontium Manganite Particles with Designable Curie Point, for Application in Hyperthermia Treatments

Silica-coated lanthanum–strontium manganite particles with La_0.76Sr_0.24MnO_3+δ stoichiometric formula, exhibiting Curie temperature at ∼40°C, were prepared by using a traditional solid-state method of synthesis of magnetic ceramic particles, followed by milling and a low-temperature coating procedure in an aqueous alcoholic alkali medium. The properties of the obtained material establish it as a potential candidate for self-regulated power-absorbing and temperature-controlling materials in hyperthermia treatments. Moreover, core-comprising LaSr–manganites with different stoichiometries, ranging from La_0.5Sr_0.5MnO_3+δ to LaMnO_3+δ, were synthesized, with magnetic and structural properties examined thereof. Herein reported findings can potentially be used in the preparation of silica-coated magnetic particles with designable Curie temperature, offering a wide range of possibilities of adapting the material to practical instrumental setups in drug delivery and hyperthermia treatments.