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991.
Jos Fbio Lana Lucas Furtado da Fonseca Gabriel Azzini Gabriel Santos Marcelo Braga Alvaro Motta Cardoso Junior William D. Murrell Alberto Gobbi Joseph Purita Marco Antonio Percope de Andrade 《International journal of molecular sciences》2021,22(5)
The rise in musculoskeletal disorders has prompted medical experts to devise novel effective alternatives to treat complicated orthopedic conditions. The ever-expanding field of regenerative medicine has allowed researchers to appreciate the therapeutic value of bone marrow-derived biological products, such as the bone marrow aspirate (BMA) clot, a potent orthobiologic which has often been dismissed and regarded as a technical complication. Numerous in vitro and in vivo studies have contributed to the expansion of medical knowledge, revealing optimistic results concerning the application of autologous bone marrow towards various impactful disorders. The bone marrow accommodates a diverse family of cell populations and a rich secretome; therefore, autologous BMA-derived products such as the “BMA Matrix”, may represent a safe and viable approach, able to reduce the costs and some drawbacks linked to the expansion of bone marrow. BMA provides —it eliminates many hurdles associated with its preparation, especially in regards to regulatory compliance. The BMA Matrix represents a suitable alternative, indicated for the enhancement of tissue repair mechanisms by modulating inflammation and acting as a natural biological scaffold as well as a reservoir of cytokines and growth factors that support cell activity. Although promising, more clinical studies are warranted in order to further clarify the efficacy of this strategy. 相似文献
992.
Mariana Gava Segatelli Gabriel Rabelo Coelho Érica Signori Romagnoli Paulo Rogério Catarini da Silva 《Ceramics International》2021,47(5):6030-6040
Ceramic materials based on silicon oxycarbide (SiOC) and reduced graphene oxide (rGO) were produced by polymer pyrolysis and evaluated in terms of phase development and porosity. Carbonaceous phase, initially prepared from graphite oxide, was incorporated into silicone dihydroxy terminated in different amounts (0, 5, 15 and 25 wt%) and submitted to pyrolysis at 1500 °C to obtain SiOC/rGO ceramics. Higher ceramic yields and more thermally stable materials were obtained after rGO addition, whose results were associated to the chemical interaction degree between rGO and polymer structure. Cgraphite and SiC phases were generated in rGO-containing ceramics and a mixture of α- and β-SiC was achieved from 15 wt% rGO, enhancing their crystallinity with increasing of rGO content. Porosity features were influenced by the carbonaceous phase amount and different rGO-polymer interaction degrees. SiOC/rGO ceramics demonstrated desirable structural characteristics for future investigations in electrical and/or electrochemical applications. 相似文献
993.
Gabriel M.S. Salvador Ana Luisa Silva Ludmila P.C. Silva Fabio B. Passos Nakédia M.F. Carvalho 《International Journal of Hydrogen Energy》2021,46(53):26976-26988
This work describes the application of α-MnO2 and Pd/α-MnO2 as electrocatalysts in the oxygen evolution reaction (OER). Characterization data revealed that the Pd2+ precursor has been oxidized during the synthesis, and the resulting Pd4+ ions have unprecedently replaced the lattice framework Mn3+ ions of α-MnO2. Furthermore, formation of PdO nanoparticles was also observed. Lower OER overpotential at j = 10 mA cm?2 (636 mV) was obtained for Pd/α-MnO2 in relation to α-MnO2 (700 mV), what is in alignment with the lower charge transfer resistance of Pd/α-MnO2 (4.9 kΩ cm2) compared to α-MnO2 (10.4 kΩ cm2). Lower Tafel slope (73 mV dec?1) and higher TOF (2.87 × 10?4 s?1) at overpotential of 350 mV was obtained for Pd/α-MnO2 in relation to α-MnO2 (Tafel of 77 mV dec?1 and TOF of 1.94 × 10?4 s?1), indicating a faster electron transfer kinetics promoted by Pd. Pd/α-MnO2 was stable at j = 14 mA cm?2 for 6 h. 相似文献
994.
Gabriel Wosiak Mariana C. Silva Jeyse da Silva Evaldo B. Carneiro-Neto Mauro C. Lopes Ernesto Pereira 《International Journal of Hydrogen Energy》2021,46(34):17644-17652
Electrochemical water splitting is a well-known reaction, investigated since 1869 due to its wide applicability for different purposes. Despite occurring at the electrode/solution interface, this set of reactions can be governed not only by interfacial properties but also by reactant transport from the solution toward the electrode surface. For water splitting specifically, the reaction mechanism itself leads to a pH change at the interface although the bulk value remains constant. In this work, we simulated such pH variations using the finite element method. The results show an interfacial pH change of up to 9 pH units. This modification in the reaction condition affects many related parameters such as electric power consumption, which increases. Thence, we investigated the effect of using an AC perturbation. In the conditions we have studied, it is observed an important delay in the pH change, although it always occurs. 相似文献
995.
Ricardo Floriano Guilherme Zepon Kaveh Edalati Gabriel L.B.G. Fontana Abbas Mohammadi Zhongliang Ma Hai-Wen Li Rodrigo J. Contieri 《International Journal of Hydrogen Energy》2021,46(46):23757-23766
Crystal structure and hydrogen storage properties of a novel equiatomic TiZrNbCrFe high-entropy alloy (HEA) were studied. The selected alloy, which had a A3B2-type configuration (A: elements forming hydride, B: elements with low chemical affinity with hydrogen) was designed to produce a hydride with a hydrogen-to-metal atomic ratio (H/M) higher than those for the AB2- and AB-type alloys. The phase stability of alloy was investigated through thermodynamic calculations by the CALPHAD method. The alloy after arc melting showed the dominant presence of a solid solution C14 Laves phase (98.4%) with a minor proportion of a disordered BCC phase (1.6%). Hydrogen storage properties investigated at different temperatures revealed that the alloy was able to reversibly absorb and fully desorb 1.9 wt% of hydrogen at 473 K. During the hydrogenation, the initial C14 and BCC crystal structures were fully converted into the C14 and FCC hydrides, respectively. The H/M value was 1.32 which is higher than the value of 1 reported for the AB2- and AB-type HEAs. The present results show that good hydrogen storage capacity and reversibility at moderate temperatures can be attained in HEAs with new configurations such as A3B2/A3B2H7. 相似文献
996.
Tomás Lafarga Ana Sánchez-Zurano Ainoa Morillas-España Francisco Gabriel Acién-Fernández 《International Journal of Food Science & Technology》2021,56(10):4934-4941
There are places in our planet where environmental conditions are beyond normal limits for growth but still harbour life. Extremophile microalgae are the candidates for large-scale production because (i) their extreme growth conditions help to avoid unwanted contaminations, facilitating their production and (ii) in order to survive under harsh environments, these microorganisms synthesise valuable uncommon biomolecules. Extremophile microalgae include Arthrospira platensis, used as a source of phycocyanin and produced under highly alkaline conditions, and Dunaliella salina, which is industrially produced as a source of β-carotene and can naturally resist salinity conditions exceeding 300 g L−1. Microalgae can be produced on non-arable lands, using seawater, and within a wide range of environmental conditions, allowing their production in almost any part of the planet. The current paper aimed at highlighting the biotechnological potential of extremophile microalgae as sources for carotenoids, valuable molecules used as pigments and health-promoters. 相似文献
997.
Gabriel Luta Mihail Butura Adrian Tiron Crina E. Tiron 《International journal of molecular sciences》2021,22(8)
Background: In the latest years, there has been an increased interest in nanomaterials that may provide promising novel approaches to disease diagnostics and therapeutics. Our previous results demonstrated that Carbon-dots prepared from N-hydroxyphthalimide (CD-NHF) exhibited anti-tumoral activity on several cancer cell lines such as MDA-MB-231, A375, A549, and RPMI8226, while U87 glioma tumor cells were unaffected. Gliomas represent one of the most common types of human primary brain tumors and are responsible for the majority of deaths. In the present in vitro study, we expand our previous investigation on CD-NHF in the U87 cell line by adding different drug combinations. Methods: Cell viability, migration, invasion, and immunofluorescent staining of key molecular pathways have been assessed after various treatments with CD-NHF and/or K252A and AKTVIII inhibitors in the U87 cell line. Results: Association of an inhibitor strongly potentiates the anti-tumoral properties of CD-NHF identified by significant impairment of migration, invasion, and expression levels of phosphorylated Akt, p70S6Kinase, or by decreasing expression levels of Bcl-2, IL-6, STAT3, and Slug. Conclusions: Using simultaneously reduced doses of both CD-NHF and an inhibitor in order to reduce side effects, the viability and invasiveness of U87 glioma cells were significantly impaired. 相似文献
998.
Simon Mathis Gabriel Putzer Stefan Schneeberger Judith Martini 《International journal of molecular sciences》2021,22(8)
The endothelial glycocalyx is a thin layer consisting of proteoglycans, glycoproteins and glycosaminoglycans that lines the luminal side of vascular endothelial cells. It acts as a barrier and contributes to the maintenance of vascular homeostasis and microperfusion. During solid organ transplantation, the endothelial glycocalyx of the graft is damaged as part of Ischemia Reperfusion Injury (IRI), which is associated with impaired organ function. Although several substances are known to mitigate glycocalyx damage, it has not been possible to use these substances during graft storage on ice. Normothermic machine perfusion (NMP) emerges as an alternative technology for organ preservation and allows for organ evaluation, but also offers the possibility to treat and thus improve organ quality during storage. This review highlights the current knowledge on glycocalyx injury during organ transplantation, presents ways to protect the endothelial glycocalyx and discusses potential glycocalyx protection strategies during normothermic machine perfusion. 相似文献
999.
1000.
Networks and Spatial Economics - Dynamic user equilibrium (DUE) is the most widely studied form of dynamic traffic assignment (DTA), in which road travelers engage in a non-cooperative Nash-like... 相似文献