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861.
Ekaterina A. Mikhaleva Igor N. Flerov Andrey V. Kartashev Mikhail V. Gorev Maxim S. Molokeev Evgeniy V. Bogdanov Vitaliy S. Bondarev Leonid N. Korotkov Ewa Rysiakiewicz-Pasek 《Journal of Materials Science》2018,53(17):12132-12144
A study of heat capacity, thermal dilatation, susceptibility to hydrostatic pressure, permittivity and polarization loops was carried out on NH4HSO4–porous glass nanocomposites (AHS?+?PG) as well as empty glass matrices. The formation of dendrite clusters of AHS with a size, dcryst, exceeding the pore size was found. An insignificant anisotropy of thermal expansion of AHS?+?PG showing statistically uniform distribution of AHS with random orientations of nanocrystallites over the matrix was observed. The effect of internal and external pressures on thermal properties and permittivity was studied. At the phase transition P-1???Pc, a strongly nonlinear decrease in the entropy ΔS2 and volume strain (ΔV/V)T2 was observed with decreasing dcryst. The linear change in temperatures of both phase transitions P-1???Pc???P21/c under hydrostatic pressure is accompanied by the expansion of the temperature range of existence of the ferroelectric phase Pc, while this interval narrows as dcryst decreases. 相似文献
862.
Ewa Ratajczak-Ropel 《控制论与系统》2013,44(5-6):296-316
ABSTRACTIn this paper, a rank-based nonparametric statistical test for measuring the effect of cooperation between optimization agents solving the multi-mode resource-constrained project scheduling problem is presented. To solve this NP-hard optimization problem, different methods are applied including population- and agent-based approaches. One of them is a team of asynchronous agents composed of multiple optimization agents, management agents, and common memories, which through interactions produce solutions of hard optimization problems. Optimization agents represent different methods including local search, path relinking, or tabu search. Interactions are managed through various cooperation strategies based on applying heuristics, reinforcement learning, or population learning. 相似文献
863.
Ewa Dostatni Jacek Diakun Damian Grajewski Radosław Wichniarek Anna Karwasz 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(11):4347-4361
In this paper, the application of multi-agent system to support decision-making process in design for recycling is presented. The design for recycling term is highlighted either as the design problem or from the point of view of regulations. The structure of agent system supporting the designer during the design process is showed. The basis of special kind of product model, that is the extension of standard 3D product model, called recycling-oriented product model, is described. The example results of analysis, based on real household appliance model, are presented. 相似文献
864.
865.
Micha Marcinkowski Toma Pilys Damian Garbicz Jan Piwowarski Damian Mielecki Grzegorz Nowaczyk Micha Taube Maciej Gielnik Maciej Kozak Maria Winiewska-Szajewska Ewa Szoajska Janusz Dbski Agnieszka M. Maciejewska Kaja Przygoska Karolina Ferenc Elbieta Grzesiuk Jarosaw Poznaski 《International journal of molecular sciences》2021,22(9)
The FTO protein is involved in a wide range of physiological processes, including adipogenesis and osteogenesis. This two-domain protein belongs to the AlkB family of 2-oxoglutarate (2-OG)- and Fe(II)-dependent dioxygenases, displaying N6-methyladenosine (N6-meA) demethylase activity. The aim of the study was to characterize the relationships between the structure and activity of FTO. The effect of cofactors (Fe2+/Mn2+ and 2-OG), Ca2+ that do not bind at the catalytic site, and protein concentration on FTO properties expressed in either E. coli (ECFTO) or baculovirus (BESFTO) system were determined using biophysical methods (DSF, MST, SAXS) and biochemical techniques (size-exclusion chromatography, enzymatic assay). We found that BESFTO carries three phosphoserines (S184, S256, S260), while there were no such modifications in ECFTO. The S256D mutation mimicking the S256 phosphorylation moderately decreased FTO catalytic activity. In the presence of Ca2+, a slight stabilization of the FTO structure was observed, accompanied by a decrease in catalytic activity. Size exclusion chromatography and MST data confirmed the ability of FTO from both expression systems to form homodimers. The MST-determined dissociation constant of the FTO homodimer was consistent with their in vivo formation in human cells. Finally, a low-resolution structure of the FTO homodimer was built based on SAXS data. 相似文献
866.
Alberta Velimirov Machteld Huber Charlotte Lauridsen Ewa Rembiałkowska Kathrin Seidel Susanne Bügel 《Journal of the science of food and agriculture》2010,90(2):175-182
Feeding experiments comparing organically and conventionally produced food are performed to assess the overall impact on the animals' health as a model for the effects experienced by the human consumers. These experiments are based on systems research and characterized by their focus on production methods, whole food testing and procedures in accordance with the terms of organic farming. A short review of such experiments shows that the majority of these tests revealed effects of the organically produced feed on health parameters such as reproductive performance and immune responses. Systems research is not just about simple cause–effect chains, but rather about the pluralism of interactions in biological networks; therefore, the interpretation of the outcome of whole food experiments is difficult. Furthermore, the test diets of organic and conventional origin can be constituted in different ways, compensating for or maintaining existing differences in nutrient and energy contents. The science‐based results suggest positive influences from organic feeds, but there is still a need for confirmation in animals and, finally, in humans. For this purpose animal feeding trials with feed from different production systems should be conducted, with the aims to define health indicators and to establish biomarkers as a basis for future dietary intervention studies in humans. Copyright © 2009 Society of Chemical Industry 相似文献
867.
A direct, high yield synthesis for preparing narrow-size silver nanoparticles by decomposition of silver carboxylate precursor
under H2 pressure (3 bars) in solution is reported. The method corresponds to that for nanoparticles synthesised by thermal decomposition
of carboxylic acid silver salts, but is faster, reproducible, versatile, and easier to control. Most of carboxylate groups
are reprotonated upon the presence of dihydrogen and subsequent reduction of Ag+ produces spherical particles of dimensions 4–6 nm. The IR studies indicate that aliphatic carboxylates chemisorb on the nanoparticle
surface with the two oxygen atoms coordinated mostly symmetrically and forming bridging bidentate Ag–O bonds. This implies
strong interactions between the surfactant and Ag nanoparticle and enhances the stability of Ag colloid. There are some sites
yet, probably at vertex or facet atoms of the nanoparticle, which form linkages of chelating bidentate or ionic character.
Silver particles can be additionally capped in situ either by aliphatic primary amines or thiols forming mixed carboxylate/amine
or carboxylate/thiol protecting monolayer. It is demonstrated that coordination of the second ligand adjusts physicochemical
properties of nanoparticles. In the dual passivating system both amine and thiol were found to be tightly bounded to the silver
nanoparticle surface. 相似文献
868.
Rafał Leszczynski Ewa Stodolak Jarosław Wieczorek Jolanta Orlowska-Heitzman Teresa Gumula Stanislaw Blazewicz 《Journal of materials science. Materials in medicine》2010,21(10):2843-2851
The aim of the work was to evaluate the in vivo biological behaviour of polymeric membrane materials for glaucoma implants.
The base material was biostable synthetic terpolymer (PTFE–PVDF–PP) with proved biocompability (PN-EN ISO 10993). The samples
manufactured in the form a membrane were subjected to chemical and physical treatment to create an open pore system within
the polymer matrix. As a porogenic phase biodegradable natrium alginate in a fibrous form was employed. The non-perforating
deep sclerectomy technique was performed in a rabbit model. The clinical observations were made after 14 and 30 days. During
the study clinical symptoms of a moderate degree were observed, and histopathological changes were typical for foreign body
implantation. At the end stage of the study no significant difference in histopathological assessment was found between control
and experimental group. Similarities observed in both groups and relatively mild histopathological changes in the tissue surrounding
the implant indicate that the observed symptoms come from a deep scleral trauma caused by surgery, and not by the presence
of the implant itself. 相似文献
869.
Tomasz Oleszkiewicz Magdalena Klimek-Chodacka Micha Kruczek Kamila Godel-Jdrychowska Katarzyna Sala Anna Milewska-Hendel Maciej Zubko Ewa Kurczyska Yiping Qi Rafal Baranski 《International journal of molecular sciences》2021,22(12)
Recent data indicate that modifications to carotenoid biosynthesis pathway in plants alter the expression of genes affecting chemical composition of the cell wall. Phytoene synthase (PSY) is a rate limiting factor of carotenoid biosynthesis and it may exhibit species-specific and organ-specific roles determined by the presence of psy paralogous genes, the importance of which often remains unrevealed. Thus, the aim of this work was to elaborate the roles of two psy paralogs in a model system and to reveal biochemical changes in the cell wall of psy knockout mutants. For this purpose, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR associated (Cas9) proteins (CRISPR/Cas9) vectors were introduced to carotenoid-rich carrot (Daucus carota) callus cells in order to induce mutations in the psy1 and psy2 genes. Gene sequencing, expression analysis, and carotenoid content analysis revealed that the psy2 gene is critical for carotenoid biosynthesis in this model and its knockout blocks carotenogenesis. The psy2 knockout also decreased the expression of the psy1 paralog. Immunohistochemical staining of the psy2 mutant cells showed altered composition of arabinogalactan proteins, pectins, and extensins in the mutant cell walls. In particular, low-methylesterified pectins were abundantly present in the cell walls of carotenoid-rich callus in contrast to the carotenoid-free psy2 mutant. Transmission electron microscopy revealed altered plastid transition to amyloplasts instead of chromoplasts. The results demonstrate for the first time that the inhibited biosynthesis of carotenoids triggers the cell wall remodelling. 相似文献
870.
Cobalt(II) sites in ferrierites are already well-known from their catalytic activity, their speciation and properties, however, the knowledge are far from completeness. The following paper presents the first in literature combined QM/MM study to elucidate the structure of these sites. With this end force-field parameters describing Co interactions with ionic shells in zeolite have been tested and the cell size for various Al distributions and Co positioning has been determined. Oxide-type Buckingham parameters are shown to perform better than the carbonate ones. Moreover, Co(II) ions stability in α and β sites with various Al distribution indicates at T1T1 Al substitution in β-site as that the preferred Co(II) siting. DFT results show that the quartet spin state of Co(II) is more stable than the doublet one. 相似文献