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91.
Radenka Krsmanovi? ?eljka Anti? Ivana Zekovi? Barbora Bártová Miroslav D. Drami?anin 《Radiation measurements》2010,45(3-6):438-440
In this work we explored the possibility of obtaining nanocrystalline (Y0.5Lu0.5)2O3 powders, doped with europium and co-doped with praseodium, employing polymer complex solution synthesis. Polyethylene glycol, with average molecular weight 200, served both as a fuel and dispersing medium for nanocrystals formation. We investigated structure, morphology, luminescence emission and decay characteristics of obtained powders and how different concentrations of Pr co-dopant affect theirs optical characteristics. 相似文献
92.
Vclav Nmec Michaela Hylsov Luk Maier Jana Flegel Sonja Sievers Slava Ziegler Martin Schrder Benedict‐Tilman Berger Apirat Chaikuad Barbora Val
íkov Stjepan Uldrijan Stanislav Drpela Karel Sou
ek Herbert Waldmann Stefan Knapp Kamil Paruch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(4):1074-1078
Reported is the identification of the furo[3,2‐b]pyridine core as a novel scaffold for potent and highly selective inhibitors of cdc‐like kinases (CLKs) and efficient modulators of the Hedgehog signaling pathway. Initially, a diverse target compound set was prepared by synthetic sequences based on chemoselective metal‐mediated couplings, including assembly of the furo[3,2‐b]pyridine scaffold by copper‐mediated oxidative cyclization. Optimization of the subseries containing 3,5‐disubstituted furo[3,2‐b]pyridines afforded potent, cell‐active, and highly selective inhibitors of CLKs. Profiling of the kinase‐inactive subset of 3,5,7‐trisubstituted furo[3,2‐b]pyridines revealed sub‐micromolar modulators of the Hedgehog pathway. 相似文献
93.
Lucia Veselovská Natálie Kudlová Dr. Soňa Gurská Dr. Barbora Lišková Martina Medvedíková Dr. Ondřej Hodek Eva Tloušťová Nemanja Milisavljevic Dr. Michal Tichý Dr. Pavla Perlíková Dr. Helena Mertlíková-Kaiserová Jana Trylčová Dr. Radek Pohl Dr. Blanka Klepetářová Dr. Petr Džubák Prof. Dr. Marián Hajdúch Prof. Dr. Michal Hocek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(57):13002-13015
All four isomeric series of novel 4-substituted pyrido-fused 7-deazapurine ribonucleosides possessing the pyridine nitrogen atom at different positions were designed and synthesized. The total synthesis of each isomeric fused heterocycle through multistep heterocyclization was followed by glycosylation and derivatization at position 4 by cross-coupling reactions or nucleophilic substitutions. All compounds were tested for cytostatic and antiviral activity. The most active were pyrido[4′,3′:4,5]pyrimidine nucleosides bearing MeO, NH2, MeS, or CH3 groups at position 4, which showed submicromolar cytotoxic effects and good selectivity for cancer cells. The mechanism involved activation by phosphorylation and incorporation to DNA where the presence of the modified ribonucleosides causes double-strand breaks and apoptosis. 相似文献
94.
Ivana Víov Barbora Smolkov Mariia Uzhytchak Markta Vrabcov Yulia Zhigunova Milan Houska Frantiek Surman Andres de los Santos Pereira Oleg Lunov Alexandr Dejneka Hana Vaisocherov‐Lísalov 《Macromolecular bioscience》2020,20(3)
Ultra‐low fouling and functionalizable coatings represent emerging surface platforms for various analytical and biomedical applications such as those involving examination of cellular interactions in their native environments. Ultra‐low fouling surface platforms as advanced interfaces enabling modulation of behavior of living cells via tuning surface physicochemical properties are presented and studied. The state‐of‐art ultra‐low fouling surface‐grafted polymer brushes of zwitterionic poly(carboxybetaine acrylamide), nonionic poly(N‐(2‐hydroxypropyl)methacrylamide), and random copolymers of carboxybetaine methacrylamide (CBMAA) and HPMAA [p(CBMAA‐co‐HPMAA)] with tunable molar contents of CBMAA and HPMAA are employed. Using a model Huh7 cell line, a systematic study of surface wettability, swelling, and charge effects on the cell growth, shape, and cytoskeleton distribution is performed. This study reveals that ultra‐low fouling interfaces with a high content of zwitterionic moieties (>65 mol%) modulate cell behavior in a distinctly different way compared to coatings with a high content of nonionic HPMAA. These differences are attributed mostly to the surface hydration capabilities. The results demonstrate a high potential of carboxybetaine‐rich ultra‐low fouling surfaces with high hydration capabilities and minimum background signal interferences to create next‐generation bioresponsive interfaces for advanced studies of living objects. 相似文献
95.
Barbora Benetková Jan Krejčí Klára Drábková Michal Ďurovič Michal Veselý Petr Dzik Jiří Akrman 《X射线光谱测定》2020,49(2):302-307
The traditional labelling of archive documents (e.g., hand stamping) entails several limitations. It could affect the aesthetic value of the archive document and is easy to find and remove in case of the theft of the document. The use of a label that would not be easily visible by the naked eye would resolve both of these problems. One possibility in designing such label is the use of the elements that have a good response in X-ray fluorescence (XRF) spectrum, are not disturbing in colour, and are not usually present in the archive materials themselves. This study focuses on such type of labelling, specifically, the tags based on the oxides of lanthanum, dysprosium, samarium, gadolinium, and niobium. For the material to be taken into account by the community, it has to fulfil several important characteristics, such as harmlessness to the archival documents, non-toxicity, or long-term stability. In the study, the long-term stability of these tags was studied on model samples of lignocellulose materials subjected to several types of artificial ageing. The colour changes and changes in the intensity of the responses of the individual elements in the XRF spectra were evaluated. To simulate the practical use, the tags of minimal visibility to the naked eye were printed on samples of real archive materials, and their potential for detection using a handheld XRF spectrometer was studied. Both of the research parts should help bring this type of labelling closer to the field application. 相似文献
96.
Barbora Štěpánková 《European Journal of Operational Research》2021,288(3):992-1005
This study proposes and analyses a novel alternative to credit transition matrices (CTMs) developed by credit rating agencies - bank-sourced CTMs. It provides a unique insight into estimation of bank-sourced CTMs by assessing the extent to which the CTMs depend on the characteristics of the underlying credit risk datasets and the aggregation method and outlines that the choice of aggregation approach has a substantial effect on credit risk model results. Further, we show that bank-sourced CTMs are more dynamic than those of credit rating agencies, with higher off-diagonal transition rates and higher propensity to upgrade. Finally, we create a set of industry-specific CTMs, otherwise unobtainable due to the data sparsity faced by credit rating agencies, and highlight the implications of their differences, signalling the existence of industry-specific business cycles. The study uses a unique and large dataset of internal credit risk estimates from 24 global banks covering monthly observations on more than 26,000 large corporates and employs large-scale Monte Carlo simulations. This approach can be replicated by regulators (e.g., data collected by the European Central Bank in the AnaCredit project) and used by organisations aiming to improve their credit risk models. 相似文献
97.
Daniel Horák Jana Kučerová Lucie Korecká Barbora Jankovičová Jiří Palarčík Petr Mikulášek Zuzana Bílková 《Macromolecular bioscience》2012,12(5):647-655
Magnetic macroporous PGMA and PHEMA microspheres containing carboxyl groups are synthesized by multi‐step swelling and polymerization followed by precipitation of iron oxide inside the pores. The microspheres are characterized by SEM, IR spectroscopy, AAS, and zeta‐potential measurements. Their functional groups enable bioactive ligands of various sizes and chemical structures to couple covalently. The applicability of these monodisperse magnetic microspheres in biospecific catalysis and bioaffinity separation is confirmed by coupling with the enzyme trypsin and huIgG. Trypsin‐modified magnetic PGMA‐COOH and PHEMA‐COOH microspheres are investigated in terms of their enzyme activity, operational and storage stability. The presence of IgG molecules on microspheres is confirmed.
98.
Petr Písařík Miroslav Jelínek Karel Smetana Jr. Barbora Dvořánková Tomáš Kocourek Josef Zemek Dagmar Chvostová 《Applied Physics A: Materials Science & Processing》2013,112(1):143-148
Optical and biomedical properties of diamond-like carbon (DLC) films of various sp2, sp3 bonds were studied. The layers were prepared by pulsed laser deposition (PLD) for laser energy densities from 4 J?cm?2 to 14 J?cm?2. The percentage of sp2 and sp3 bonds was calculated using X-ray photoelectron spectroscopy (XPS). In dependence on density the films contained up to 70 % of sp3 bonds. Optical properties were measured using spectroscopic ellipsometry in region from 250 nm to 1000 nm (n=2.6–2.7; k=0.07–0.25) and by transmission measurement (from 200 nm to 1100 nm). The adhesion and growth of human fibroblasts and keratinocytes of DLC films were tested in vitro. 相似文献
99.
100.
Bednár P Papousková B Müller L Barták P Stávek J Pavlousek P Lemr K 《Journal of separation science》2005,28(12):1291-1299
Hyphenation of capillary electrophoresis with electrospray ionization mass spectrometry was utilized for the monitoring of anthocyanins in wine and wine musts. CE/MS was performed in two electrolytes: 1) an acidic one (chloroacetate-ammonium, pH 2) and 2) a basic one with high selectivity towards derivatives containing vicinal hydroxy groups (borate-ammonium, pH 9). The setup of MS was optimized and the fragmentation of common anthocyanins was studied in detail. Attention was also focused on the fragmentation of anthocyanidin skeleton. The anthocyanidins substituted with hydroxy groups fragment via a cascade of neutral losses of water and carbon monoxide. Fragmentation of anthocyanidins containing a methoxy group on their B-ring starts with the cleavage of methane and/or methyl radical. The optimized method was utilized for the monitoring of changes in anthocyanin profile in red wines as well as the process of release of anthocyanins to wine must. 相似文献