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31.
Angela Dziedzic Joanna Saluk-Bijak Elzbieta Miller Marcin Niemcewicz Michal Bijak 《International journal of molecular sciences》2021,22(4)
The novel coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global challenge. Currently, there is some information on the consequences of COVID-19 infection in multiple sclerosis (MS) patients, as it is a newly discovered coronavirus, but its far-reaching effects on participation in neurodegenerative diseases seem to be significant. Recent cases reports showed that SARS-CoV-2 may be responsible for initiating the demyelination process in people who previously had no symptoms associated with any nervous system disorders. It is presently known that infection of SARS-CoV-2 evokes cytokine storm syndrome, which may be one of the factors leading to the acute cerebrovascular disease. One of the substantial problems is the coexistence of cerebrovascular disease and MS in an individual’s life span. Epidemiological studies showed an enhanced risk of death rate from vascular disabilities in MS patients of approximately 30%. It has been demonstrated that patients with severe SARS-CoV-2 infection usually show increased levels of D-dimer, fibrinogen, C-reactive protein (CRP), and overactivation of blood platelets, which are essential elements of prothrombotic events. In this review, the latest knowledge gathered during an ongoing pandemic of SARS-CoV-2 infection on the neurodegeneration processes in MS is discussed. 相似文献
32.
François Béguin Volker Presser Andrea Balducci Elzbieta Frackowiak 《Advanced materials (Deerfield Beach, Fla.)》2014,26(14):2219-2251
Electrical energy storage (EES) is one of the most critical areas of technological research around the world. Storing and efficiently using electricity generated by intermittent sources and the transition of our transportation fleet to electric drive depend fundamentally on the development of EES systems with high energy and power densities. Supercapacitors are promising devices for highly efficient energy storage and power management, yet they still suffer from moderate energy densities compared to batteries. To establish a detailed understanding of the science and technology of carbon/carbon supercapacitors, this review discusses the basic principles of the electrical double‐layer (EDL), especially regarding the correlation between ion size/ion solvation and the pore size of porous carbon electrodes. We summarize the key aspects of various carbon materials synthesized for use in supercapacitors. With the objective of improving the energy density, the last two sections are dedicated to strategies to increase the capacitance by either introducing pseudocapacitive materials or by using novel electrolytes that allow to increasing the cell voltage. In particular, advances in ionic liquids, but also in the field of organic electrolytes, are discussed and electrode mass balancing is expanded because of its importance to create higher performance asymmetric electrochemical capacitors. 相似文献
33.
Alistair Forbes Paul Tomlins Elzbieta Gurdak Matthew Illsely Stuart James Elizabeth James 《Journal of materials science. Materials in medicine》2010,21(8):2463-2477
In this paper, we describe techniques for extracting features from surface topography data, gathered by a 3D-microscopy system,
on a length scale that is relevant for cell attachment. The feature parameters considered include standard surface roughness
parameters applied to the complete surface as well as new feature parameters designed to quantify local variations in surface
topography potentially influencing cell behaviour. Methodologies have been developed both to determine the degree of homogeneity
or isotropy of a surface and to compare the topographies of different samples. The approaches followed include wavelet decomposition
and linear and nonlinear filtering techniques. The analysis has been used to investigate the correlation between osteoblast
cell attachment and structural features of titanium-coated surfaces representative of orthopaedic implants. The results confirm
that there is a discernible correlation between cell orientation and the underlying surface lay. 相似文献
34.
Izabella Rajzer Elzbieta Menaszek Lucie Bacakova Monika Rom Marta Blazewicz 《Journal of materials science. Materials in medicine》2010,21(9):2611-2622
In the present study we focused on the in vitro and in vivo evaluation of two types of carbon fibres (CFs): hydroxyapatite
modified carbon fibres and porous carbon fibres. Porous CFs used as scaffold for tissues regeneration could simultaneously
serve as a support for drug delivery or biologically active agents which would stimulate the tissue growth; while addition
of nanohydroxyapatite to CFs precursor can modify their biological properties (such as bioactivity) without subsequent surface
modifications, making the process cost and time effective. Presented results indicated that fibre modification with HAp promoted
formation of apatite on the fibre surface during incubation in simulated body fluid. The materials biocompatibility was determined
by culturing human osteoblast-like cells of the line MG 63 in contact with both types of CFs. Both tested materials gave good
support to adhesion and growth of bone-derived cells. Materials were implanted into the skeletal rat muscle and a comparative
analysis of tissue reaction to the presence of the two types of CFs was done. Activities of marker metabolic enzymes: cytochrome
c oxidase (CCO) and acid phosphatase were examined to estimate the effect of implants on the metabolic state of surrounding
tissues. Presented results evidence the biocompatibility of porous CFs and activity that stimulates the growth of connective
tissues. In case of CFs modified with hydroxyapatite the time of inflammatory reaction was shorter than in case of traditional
CFs. 相似文献
35.
Highly ordered porous carbon materials obtained by a replica technique have been used for supercapacitor application and electrochemical hydrogen storage. For the preparation of the well-tailored carbons, MCM-48, SBA-15 and MSU-1 molecular sieves served as templates, whereas a sucrose solution, propylene and pitch were the carbon source. A careful physico-chemical characterization (CO2 and N2 adsorption, X-ray diffraction, electron microscopy observations) allowed to estimate the total surface area, the pore size distribution, the micro/mesopore volume as well as the structure and the microtexture of the investigated carbons. The specific capacitance (F/g) and the hydrogen adsorption capacity in the carbon nanopores were correlated with the microtextural properties. Especially, a linear dependence has been found between the capacitance or the amount of electrochemically stored hydrogen and the ultramicropores (pores smaller than 0.7 nm) volume. It clearly indicates that in these carbons: (a) the major part of the electrical double layer is charged with non-solvated ions; (b) ultramicropores play a determinant role for hydrogen storage. 相似文献
36.
37.
Zhang W Rozniecka E Malinowska E Parzuchowski P Meyerhoff ME 《Analytical chemistry》2002,74(17):4548-4557
A novel transduction chemistry for preparing optical anion-selective polymeric films that respond reversibly and selectively to chloride ion activity is demonstrated. The chloride sensors are prepared by casting thin (5-10 microm) plasticized PVC films containing indium(III) octaethylporphyrin hydroxide, along with optimized levels of a lipophilic tetraphenylborate salt, onto glass slides. When bathed in low-pH buffered solutions void of chloride, the porphyrin species spontaneously forms a hydroxide ion-bridged dimer, with the added lipophilic borate species serving as the counteranion for this complex. The maximum for the Soret absorption band of this dimeric species is shifted to 390 nm, from 410 nm for the initial monomeric porphyrin. Increases in chloride ion levels in the bathing solution results in chloride extraction and ligation to the In(III) center, and concomitant breaking of the dimer into monomeric porphyrin species, yielding a decrease in absorbance at 390 nm and an increase in optical signal at 410 nm. Under optimized conditions, optical selectivity coefficients toward chloride over a wide range of other anions (NO3-, ClO4-, SCN-, SO4(2-), F-, Br-, H2PO4-) are measured to be < 10(-3). Of all anions tested, only salicylate yields a slightly greater response than chloride. This selectivity is shown to be adequate for reversible and accurate sensing of chloride levels in diluted serum samples. 相似文献
38.
Delpeux S Szostak K Frackowiak E Bonnamy S Béguin F 《Journal of nanoscience and nanotechnology》2002,2(5):481-484
For the first time, multiwalled carbon nanotubes (MWNTs) could be formed selectively in a high yield, free of any disordered carbon by-product, from the catalytic decomposition of acetylene at 600 degrees C on a CoxMg(1-x)O solid solution. Starting from 1 g of catalytic substrate, 4 g of pure MWNTs were obtained after its dissolution in boiling concentrated HCl, without any additional purification in strongly oxidizing medium, as is required for other methods of nanotube production. In situ reduction of CoO by dihydrogen liberated from acetylene decomposition allows highly divided metal particles to be continuously produced as synthesis proceeds. This is undoubtedly the reason for the good performance of the catalyst and for the ability to produce nanotubes in a narrow diameter range, namely from 10 to 15 nm. With the use of acetylene instead of methane, the synthesis proceeds at low temperature, which prevents the growth of carbon shells, in which the metal particles are generally embedded, decreasing their activity. Because of the very low specific surface area of the catalyst support, the amount of disordered carbon by-product formed is negligible. 相似文献
39.
Tatara E Materna K Schaadt A Bart HJ Szymanowski J 《Environmental science & technology》2005,39(9):3110-3115
The cloud point separation of Direct Yellow from micellar solution of various nonionic surfactants, containing a polyoxyethylene chain, was studied. The separation of dyes is an important environmental problem. Moreover, such separation can also be considered as a preliminary step for further studies of biochemical recovery. Some dyes can be considered as affinity ligands, which form complexes with biochemicals. The use of dye enabled the observation of the dynamics of surfactant-rich phase separation by means of a color video. It was found that the separation of phases was incomplete. The aqueous phase contained some amounts of surfactant globules with the dye. The surfactant-rich phase was usually more heterogenic than the aqueous phase. The recovery of Direct Yellow was very effective in the presence of electrolyte (NaCl). The distribution coefficients were high and equal to a few hundreds in the presence of sodium chloride. Under optimum conditions 98-99.9% of the dye could be removed in the one step. 相似文献
40.
Several types of microfiltration membranes — polypropylene, cellulose diacetate (nominal pore size=0.2 μm) and polycarbonate (pore size=0.4 μm) — were tested for their microorganism retention ability. Suspensions of Pseudomonas diminuta and bovine red blood cells (RBC) were used for experimental purposes as representatives of microorganisms. Based on microscopy and microbiological evaluation it was demonstrated that individual cells of both types are able to cross a membranes that is generally rated as an aseptic one. A simple mathematical model is also proposed to describe the process by which the cells are transported across the membrane. 相似文献