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581.
Elisa Ortiz‐Rivero Katarzyna Prorok Michal Skowickł Dasheng Lu Artur Bednarkiewicz Daniel Jaque Patricia Haro‐González 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(46)
Near‐infrared‐light‐mediated optical tweezing of individual upconverting particles has enabled all‐optical single‐cell studies, such as intracellular thermal sensing and minimally invasive cytoplasm investigations. Furthermore, the intrinsic optical birefringence of upconverting particles renders them light‐driven luminescent spinners with a yet unexplored potential in biomedicine. In this work, the use of upconverting spinners is showcased for the accurate and specific detection of single‐cell and single‐bacteria attachment events, through real‐time monitoring of the spinners rotation velocity of the spinner. The physical mechanisms linking single‐attachment to the angular deceleration of upconverting spinners are discussed in detail. Concomitantly, the upconversion emission generated by the spinner is harnessed for simultaneous thermal sensing and thermal control during the attachment event. Results here included demonstrate the potential of upconverting particles for the development of fast, high‐sensitivity, and cost‐effective systems for single‐cell biodetection. 相似文献
582.
Ewa Rząd Tomasz Polczyk Łukasz Boroń Paweł Figiel Monika Solecka Tomasz Dudziak Artur Oziębło Danuta Chmielewska Barbara Synowiec Paweł Pichniarczyk 《International Journal of Applied Ceramic Technology》2021,18(3):913-927
The study was carried out in order to evaluate oxidation resistance of the ceramic coatings based on SiO2-B2O3-TiO2-Na2O composition deposited on the low-alloyed steel T/P22 (10H2M) surface exposed for 1000 h at 540°C in oxidation atmosphere. Kinetic data were recorded periodically every 250 h; macro- and microanalyses as well as chemical composition were carried out using macrolenses, SEM, EDS, EDS X-ray mappings. The results indicated a high degree of protection by ceramic coatings; much lower mass gain was observed for the coated materials than for the uncoated T/P22 (10H2M) steel. No detachment, delamination, chipping of a coating were found from the steel surface; some of the coatings showed perpendicular tiny cracks to the bulk metal surface. 相似文献
583.
Tarek R. Besold Artur d’Avila Garcez Keith Stenning Leendert van der Torre Michiel van Lambalgen 《Minds and Machines》2017,27(1):37-77
This article aims to achieve two goals: to show that probability is not the only way of dealing with uncertainty (and even more, that there are kinds of uncertainty which are for principled reasons not addressable with probabilistic means); and to provide evidence that logic-based methods can well support reasoning with uncertainty. For the latter claim, two paradigmatic examples are presented: logic programming with Kleene semantics for modelling reasoning from information in a discourse, to an interpretation of the state of affairs of the intended model, and a neural-symbolic implementation of input/output logic for dealing with uncertainty in dynamic normative contexts. 相似文献
584.
585.
AbstractThe article presents the results of the experiments of gas-admixing foam spray drying microencapsulation of oil in co-current spray drying tower. The introduction of a foaming gas resulted in a decrease of encapsulation efficiency: for high foaming gas/liquid ratio (GLR) 6.43·10?3 kg/kg and Tair,0=215?°C by over 50% relative to the non-foaming process due to damage of the microcapsule structure and leakage of the oil phase to the particle surface. For moderate drying temperatures and GLR, 80% of microencapsulation efficiency might be achieved with simultaneous control of selected product properties like apparent and bulk density or angle of repose. Abbreviations GLR gas-to-liquid ratio HR Hausner ratio MDX maltodextrin PSD particle size distribution SEM scanning electron microscope. 相似文献
586.
Novella-Rodríguez S Veciana-Nogués MT Roig-Sagués AX Trujillo-Mesa AJ Vidal-Carou MC 《The Journal of dairy research》2004,71(2):245-252
The effect of the hygienic quality of milk on changes in microbial counts and biogenic amine content was evaluated during ripening of goat cheeses manufactured from pasteurized and raw milks at 1, 14, 30, 60 and 90 d. The original milk, rennet, curd and whey were also included in the study. The pH, salt content and extent of proteolysis in the cheese were also evaluated. Spermidine and spermine were the main amines in raw milk, while they were minor amines in cheeses. Other amines increased markedly during ripening, tyramine being the main amine in cheese made from raw milk and cadaverine and putrescine in those produced from pasteurized milk. Enterobacteriaceae counts decreased during ripening whereas those of lactic acid bacteria increased, especially lactobacilli and enterococci. Cheese made from raw milk showed higher microbial counts during ripening than those made from pasteurized milk, especially for Enterobacteriaceae and enterococci, counts being 2 or 3 log units higher. Raw milk cheese showed remarkably higher biogenic amines compared with pasteurized milk cheeses. Therefore, pasteurization of milk causes a decrease in final biogenic amine content of cheese as a result of the reduction of its microbial counts. 相似文献
587.
Artur Podhorodecki Grzegorz Zatryb Lukasz W Golacki Jan Misiewicz Jacek Wojcik Peter Mascher 《Nanoscale research letters》2013,8(1):98
Silicon nanocrystals embedded in a silicon-rich silicon oxide matrix doped with Er3+ ions have been fabricated by electron cyclotron resonance plasma-enhanced chemical vapor deposition. Indirect excitation of erbium photoluminescence via silicon nanocrystals has been investigated. Temperature quenching of the photoluminescence originating from the silicon nanocrystals and the erbium ions has been observed. Activation energies of the thermally activated quenching process were estimated for different excitation wavelengths. The temperature quenching mechanism of the emission is discussed. Also, the origin of visible emission and kinetic properties of Er-related emission have been discussed in details. 相似文献
588.
Nicola Cefarin Diana E. Bedolla Artur Surowka Sandro Donato Thomas Sepperer Gianluca Tondi Diego Dreossi Nicola Sodini Giovanni Birarda Lisa Vaccari 《International journal of molecular sciences》2021,22(23)
Tannin-furanic rigid foams are bio-based copolymers of tannin plant extract and furfuryl alcohol, promising candidates to replace synthetic insulation foams, as for example polyurethanes and phenolics, in eco-sustainable buildings thanks to their functional properties, such as lightness of the material and fire resistance. Despite their relevance as environmental-friendly alternatives to petroleum derivatives, many aspects of the polymerization chemistry still remain unclear. One of the open issues is on the spatial heterogeneity of the foam, i.e., whether the foam constituents prevalently polymerize in spatially segregated blocks or distribute almost homogenously in the foam volume. To address this matter, here we propose a multiscale FTIR study encompassing 1D FTIR spectroscopy, 2D FTIR imaging and 3D FTIR micro-tomography (FTIR-μCT) on tannin-furanic rigid foams obtained by varying the synthesis parameters in a controlled way. Thanks to the implementation of the acquisition and processing pipeline of FTIR-μCT, we were able for the first time to demonstrate that the polymer formulations influence the spatial organization of the foam at the microscale and, at the same time, prove the reliability of FTIR-μCT data by comparing 2D FTIR images and the projection of the 3D chemical images on the same plane. 相似文献
589.
Multiobjective constrained optimizations are carried out to compute optimal operation policies for batch solution polymerizations of styrene. It is shown by simulations how specified values for conversion, average molecular weight, and polydispersity may be achieved through the proper manipulation of the temperature profile and the initial amounts of the initiator, chain-transfer agent (modifier), and inhibitor. The optimizations show that the use of inhibitors and/or modifiers is seldomly required, unless the process economics is taken into consideration or the high-molecular weight chain fraction of the final polymer resin is to be minimized. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1137–1152, 1998 相似文献
590.
Justyna Kowalska Klaudia Banach Jakub Rok Artur Beberok Zuzanna Rzepka Dorota Wrzeniok 《International journal of molecular sciences》2020,21(24)
Phototoxicity of fluoroquinolones is connected with oxidative stress induction. Lomefloxacin (8-halogenated derivative) is considered the most phototoxic fluoroquinolone and moxifloxacin (8-methoxy derivative) the least. Melanin pigment may protect cells from oxidative damage. On the other hand, fluoroquinolone–melanin binding may lead to accumulation of drugs and increase their toxicity to skin. The study aimed to examine the antioxidant defense system status in normal melanocytes treated with lomefloxacin and moxifloxacin and exposed to UV-A radiation. The obtained results demonstrated that UV-A radiation enhanced only the lomefloxacin-induced cytotoxic effect in tested cells. It was found that fluoroquinolones alone and with UV-A radiation decreased superoxide dismutase (SOD) activity and SOD1 expression. UV-A radiation enhanced the impact of moxifloxacin on hydrogen peroxide-scavenging enzymes. In turn, lomefloxacin alone increased the activity and the expression of catalase (CAT) and glutathione peroxidase (GPx), whereas UV-A radiation significantly modified the effects of drugs on these enzymes. Taken together, both analyzed fluoroquinolones induced oxidative stress in melanocytes, however, the molecular and biochemical studies indicated the miscellaneous mechanisms for the tested drugs. The variability in phototoxic potential between lomefloxacin and moxifloxacin may result from different effects on the antioxidant enzymes. 相似文献