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41.
Jeanne Volatron Florent Carn Jelena Kolosnjaj‐Tabi Yasir Javed Quoc Lam Vuong Yves Gossuin Christine Ménager Nathalie Luciani Gaëlle Charron Miryana Hémadi Damien Alloyeau Florence Gazeau 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(2)
Proteins implicated in iron homeostasis are assumed to be also involved in the cellular processing of iron oxide nanoparticles. In this work, the role of an endogenous iron storage protein—namely the ferritin—is examined in the remediation and biodegradation of magnetic iron oxide nanoparticles. Previous in vivo studies suggest the intracellular transfer of the iron ions released during the degradation of nanoparticles to endogenous protein cages within lysosomal compartments. Here, the capacity of ferritin cages to accommodate and store the degradation products of nanoparticles is investigated in vitro in the physiological acidic environment of the lysosomes. Moreover, it is questioned whether ferritin proteins can play an active role in the degradation of the nanoparticles. The magnetic, colloidal, and structural follow‐up of iron oxide nanoparticles and proteins in lysosome‐like medium confirms the efficient remediation of potentially harmful iron ions generated by nanoparticles within ferritins. The presence of ferritins, however, delays the degradation of particles due to a complex colloidal behavior of the mixture in acidic medium. This study exemplifies the important implications of intracellular proteins in processes of degradation and metabolization of iron oxide nanoparticles. 相似文献
42.
Aproposal to use a high-angle echelle in the vacuum UV in the 350th order triggered a theoretical study to determine if there were unusual obstacles to success. No serious obstacles were found except for efficiency limitations. 相似文献
43.
A new method of autoallodermoplasty is proposed which is as follows: a patient's skin band is cut out 40 times less than the total area of the wound surface. The wound in the donor area is sutured tightly. The skin flap is dissected to thin transverse rectangular pieces with a special microdermatome or with a razor and then they are laid with their lateral side onto the wound and covered with the allo-skin. Experimental and clinical observations have shown that at remote terms both the anatomical and functional restitution of the integument occurred. The method is indicated for huge dermal defects of the "functionally passive" areas in patients with restricted, not big resources of the donor sites, especially in patients with high operative risk. 相似文献
44.
I. V. Popov I. V. Fryazinov M. Yu. Stanichenko A. V. Taimanov 《Mathematical Models and Computer Simulations》2010,2(3):281-292
New approximations of Navier-Stokes equations are proposed for incompressible fluid on triangular and tetrahedral grids in
the predictor-corrector method. Estimates are presented for the unconditional stability of difference schemes, and calculation
results for a two-dimensional problem about a fluid flow in a cavity with a floating top cover; and they are compared with
the solutions of other authors. The problems of grid equations monotonization are discussed. 相似文献
45.
A. Yu. Popov 《Automation and Remote Control》2009,70(4):721-727
Consideration was given to minimization of the L 1-norm of control of the linear oscillatory system. For consumption of the energy resources required to damp oscillations, bilateral estimates were obtained. 相似文献
46.
Assessment of software COTS components is an essential part of component-based software development. Poorly chosen components may lead to solutions of low quality and that are difficult to maintain. The assessment may be based on incomplete knowledge about the COTS component itself and other aspects (e.g. vendor’s credentials, etc.), which may affect the decision of selecting COTS component(s). We argue in favor of assessment methods in which uncertainty is explicitly represented (‘uncertainty explicit’ methods) using probability distributions. We provide details of a Bayesian model, which can be used to capture the uncertainties in the simultaneous assessment of two attributes, thus, also capturing the dependencies that might exist between them. We also provide empirical data from the use of this method for the assessment of off-the-shelf database servers which illustrate the advantages of ‘uncertainty explicit’ methods over conventional methods of COTS component assessment which assume that at the end of the assessment the values of the attributes become known with certainty. 相似文献
47.
V. S. Popov 《Automation and Remote Control》2001,62(5):842-846
The author relies on the symmetry principle to propose variants of relative and reduced errors. Their characteristics and properties are discussed. Interrelations between various variants of errors are analyzed. A new quantitative definition of the instrument accuracy is given. 相似文献
48.
49.
A.S. Popov E.V. Popova T.V. Nikishina O.N. Vysotskaya 《International Journal of Refrigeration》2006,29(3):403
Cryopreservation is the most reliable method for long-term storage of plant genetic resources. A review of cell injury by ice crystals and dehydration during a freeze–thaw cycle is given. For successful regeneration of plants and cultures after cryopreservation of their cells, the development of reliable cryopreservation procedure is required including preliminary cultivation, treatment by cryoprotectors, freezing by different methods, thawing and recultivation. Up to now 27 cell lines successfully resumed their growth after storage in liquid nitrogen and preserved their specific features and biosynthetic potential. Besides, shoot tips of 40 cultivars of potato, rose, strawberry and raspberry regenerated plants both in vitro and in vivo after cryopreservation. The longest storage duration was 25 years. Now in liquid nitrogen we continuously store 24 cell strains of rare medicinal plants, shoot tips of seven cultivars of strawberry and raspberry and seeds of 250 endangered plant species collected over all Russian territory. 相似文献
50.
Thin amorphous chalcogenide films from the GeSex (x = 1-5), (GeSe4)100−yGay and (GeSe5)100−y Ga(Tl, B)y (y = 5, 10, 15, 20) systems have been prepared by thermal evaporation and characterized with respect to their internal stress using a cantilever technique. The correlations between the stress, the composition and the structure of the films were investigated. The obtained results were related with some structural and mechanical parameters of the glasses like mean coordination number, number of constrains per atom, density, compactness, microhardness and Young's modulus. For all investigated chalcogenide films a stress relaxation with the time was observed as a result of spontaneous structural rearrangements. 相似文献