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101.
Jana Zdarova Karasova Martin Mzik Tomas Kucera Zbynek Vecera Jiri Kassa Vit Sestak 《International journal of molecular sciences》2020,21(21)
Antidotes against organophosphates often possess physicochemical properties that mitigate their passage across the blood–brain barrier. Cucurbit[7]urils may be successfully used as a drug delivery system for bisquaternary oximes and improve central nervous system targeting. The main aim of these studies was to elucidate the relationship between cucurbit[7]uril, oxime K027, atropine, and paraoxon to define potential risks or advantages of this delivery system in a complex in vivo system. For this reason, in silico (molecular docking combined with umbrella sampling simulation) and in vivo (UHPLC—pharmacokinetics, toxicokinetics; acetylcholinesterase reactivation and functional observatory battery) methods were used. Based on our results, cucurbit[7]urils affect multiple factors in organophosphates poisoning and its therapy by (i) scavenging paraoxon and preventing free fraction of this toxin from entering the brain, (ii) enhancing the availability of atropine in the central nervous system and by (iii) increasing oxime passage into the brain. In conclusion, using cucurbit[7]urils with oximes might positively impact the overall treatment effectiveness and the benefits can outweigh the potential risks. 相似文献
102.
Nima Hematyar Tomas Policar Azadeh Mohagheghi Samarin Sabine Sampels Ievgeniia Gazo Jan Mraz 《International Journal of Food Science & Technology》2020,55(12):3622-3629
Microbial activity and then oxidation progress are the most important freshness indicators during post-mortem. In this study, we monitored proteomic and microbial changes, as well as biochemical degradation, in the tail and claw muscles of crayfish stored for 12 days at +4 °C. One specified protein band at 107 kDa in the claw muscle and two specified protein bands in the tail muscle at 140 and 36–40 kDa were identified. Western blotting indicated a higher amount of oxidised proteins in the tail compared to the claw muscle. Tail muscle showed higher oxidation progress and calpain activity than claw one. Both muscles were spoiled after 12 days with respect to total viable counts. In the first days, calpain activity is the main reason for protein degradation, while protein oxidation dominates for the rest of the time. Lipid–protein oxidation progress showed probably, protein oxidation started earlier than lipid oxidation in both muscles. 相似文献
103.
A techno‐economic analysis for four different types of biogas plant realizations was performed, including one biogas biorefinery concept. For each concept detail, a process flow diagram was created. Mass and energy balances were estimated. The net present value and payback were calculated for each concept for a better feasibility understanding. The results showed that with the used expensive substrate, namely, wheat straw, the obtained paybacks appeared to be more than 100 years. Sensitivity analysis was done for the price range of a substrate. Critical factors were defined to improve feasibility. 相似文献
104.
Most industrial process lines involve mixing complex dispersions, which can include non-Newtonian liquids and viscoelastic particles. Knowledge of the parameters of these components may provide a key for understanding how dispersions are formed and how equipment should be designed. One parameter is the shear modulus, which describes the ability of particles to resist mechanical stresses. This parameter may play the main role in the mixing process, when a dispersion is formed by the mechanical influence of a rotor (slice or shear in a rotor-stator mixer). In this work, two methods were chosen for measuring the shear modulus: the evaluation method, based on the Warner-Bratzler cut test, and the oscillatory method. Both methods were used for measuring viscoelastic clusters of particles, and the results were adjusted for the purposes of the comparison. The comparison shows that the shear modulus values obtained from Warner-Bratzler are higher than the values obtained from the oscillatory test for the same conditions. This difference can be explained by differences in the mechanical processes during the experiments. 相似文献
105.
Tomas Plachy Milan Masar Miroslav Mrlik Michal Machovsky Zuzana Machovska Erika Kutalkova Ivo Kuritka 《Advanced Powder Technology》2019,30(4):714-723
Investigation of pristine g-C3N4 and copper ions doped g-C3N4 as dispersed phases in silicone-oil based electrorheological (ER) fluids is reported for the first time. Pristine g-C3N4 was prepared via standard thermal polycondensation of urea. Introduction of Cu ions into g-C3N4 polymeric network was performed by treatment of pristine powder by a solution containing tetraammoniumdiaquacopper(II) complex ions followed by annealing. The structure and properties of products were revealed with the aid of XRD, FTIR, UV–Vis and XPS, and complemented by SEM investigation of morphology, pycnometry, BET analysis, and conductivity measurements. The response of prepared ER fluids to an external electric field was examined by rheometry and the effects visualized with optical microscopy. While ER fluids based on g-C3N4 exhibited negative ER effect (decrease in viscosity when the field is switched-on), ER fluids based on a g-C3N4/Cu-doped analogue exhibited positive ER effect. Dielectric spectroscopy using Havriliak-Negami model revealed that introduction of the dopant almost doubled the dielectric relaxation strength while the relaxation time was halved. The ability of g-C3N4/Cu as a candidate for further studies necessary to increase the ER effect was demonstrated. Thereto, described modification of g-C3N4 by copper ions shall be applicable also for other metals forming ammonia complexes. 相似文献
106.
Mohammad Mahdi Tavakoli Giovanni Azzellino Marek Hempel Ang‐Yu Lu Francisco J. Martin‐Martinez Jiayuan Zhao Jingjie Yeo Tomas Palacios Markus J. Buehler Jing Kong 《Advanced functional materials》2020,30(31)
A roll‐to‐roll (R2R) transfer technique is employed to improve the electrical properties of transferred graphene on flexible substrates using parylene as an interfacial layer. A layer of parylene is deposited on graphene/copper (Cu) foils grown by chemical vapor deposition and are laminated onto ethylene vinyl acetate (EVA)/poly(ethylene terephthalate). Then, the samples are delaminated from the Cu using an electrochemical transfer process, resulting in flexible and conductive substrates with sheet resistances of below 300 Ω sq?1, which is significantly better (fourfold) than the sample transferred by R2R without parylene (1200 Ω sq?1). The characterization results indicate that parylene C and D dope graphene due to the presence of chlorine atoms in their structure, resulting in higher carrier density and thus lower sheet resistance. Density functional theory calculations reveal that the binding energy between parylene and graphene is stronger than that of EVA and graphene, which may lead to less tear in graphene during the R2R transfer. Finally, organic solar cells are fabricated on the ultrathin and flexible parylene/graphene substrates and an ultra‐lightweight device is achieved with a power conversion efficiency of 5.86%. Additionally, the device shows a high power per weight of 6.46 W g?1 with superior air stability. 相似文献
107.
108.
Lukas Strizik Vit Prokop Jan Hrabovsky Tomas Wagner Takeshi Aoki 《Journal of Materials Science: Materials in Electronics》2017,28(10):7053-7063
The article presents the formulas of quadrature frequency resolved spectroscopy (QFRS) on the upconversion photoluminescence (UCPL) of rare-earth (RE) doped materials on the general M-level model. The formulas are derived in matrix-equation form with the first-order perturbation on the rate equations at the M energy-levels of RE ion. The QFRS spectra for three different UCPL processes, i.e., the excited state absorption (ESA), energy transfer upconversion (ETU) and photon avalanche (PA) via cross relaxation process (CRP) in a particular case of M?=?3 are demonstrated with the respective salient features of the excitation power dependence. We have measured the QFRS on the UCPL (4 S 3/2 → 4 I 15/2) by systematically varying Er-doping in Ge28.1Ga6.3S65.6 chalcogenide glass from 0.01 to 0.5 at.% as well as 975 nm excitation power. Thereby the relaxation rates k 1 at the intermediate level 4 I 11/2, k 2 at the top level 4 S 3/2 and ETU parameter w are determined as a function of Er concentration. The UCPL dynamics on the basis of the formulas for the 3-level model is interpreted in terms of the determined parameters. 相似文献
109.
As an extension of fuzzy set, a Pythagorean fuzzy set has recently been developed to model imprecise and ambiguous information in practical group decision‐making problems. The aim of this paper is to introduce a novel aggregation method for the Pythagorean fuzzy set and analyze possibilities for its application in solving multiple attribute decision‐making problems. More specifically, a new Pythagorean fuzzy aggregation operator called the Pythagorean fuzzy induced ordered weighted averaging‐weighted average (PFIOWAWA) operator is developed. This operator inherits main characteristics of both ordered weighted average operator and induced ordered weighted average to aggregate the Pythagorean fuzzy information. Some of main properties and particular cases of the PFIOWAWA operator are studied. A method based on the proposed operator for multiple attribute group decision making is developed. Finally, we present a numerical example of selection of research and development projects to illustrate applicability of the new approach in a multiple attribute group decision‐making problem. 相似文献
110.
Adam Viktorin Roman Senkerik Michal Pluhacek Tomas Kadavy 《International Journal of Parallel, Emergent and Distributed Systems》2018,33(5):450-459
AbstractIn this paper, two modifications are proposed to the Progressive Random Walk (PRW) algorithm in order to address its potentially insufficient search space coverage. The first modification replaces the Pseudo-Random Number Generator (PRNG) with the uniform distribution by the chaotic map based PRNG for generating of the offset values and the second modification is called direction switching and is based on experiment observation. The modifications are implemented into the PRW and the resulting algorithm is called modified Progressive Random Walk. The search space coverage of the two algorithms is compared. Both algorithms are used in macro ruggedness estimation of the CEC2015 benchmark set and the results are discussed. 相似文献