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91.
Gbor Horvth Istvn Hermecz gnes Horvth Marianna Pongor-Cskvri Levente Pusztay rpd Istvn Kiss Lszl Czak Osman Hassan Abdirizak 《Journal of heterocyclic chemistry》1985,22(2):481-489
The characteristic features of ir and uv spectra of 43 4H-pyrido[1,2-a]pyrimidin-4-one derivatives with electron donor or acceptor groups in position 3, and positions 6, 7, 8, or 9, respectively, have been systematically studied. On the basis of the spectra some conclusions have been drawn for the molecular structure. The negative solvent effect of the lowest-energy π → π* transition is investigated by the PPP method. 相似文献
92.
Shunichi Murata Marianna S. Safronova Ulyana I. Safronova Nobuyuki Nakamura 《X射线光谱测定》2020,49(1):200-203
We present visible to near-infrared spectra of highly charged Yb (the atomic number 70) and W (74) obtained with a compact electron beam ion trap. By observing the dependence on the electron beam energy, the charge state that should be assigned to the observed lines is determined. For In-like Yb21+ and W25+ and Sn-like W24+, the experimental spectra are compared with theoretical calculations done by the CI+all-order method. In each spectrum, the most prominent line is identified as the magnetic dipole transition from the first excited fine structure level to the ground level in the ground electronic configuration, 4f3 for In-like ions and 4f4 for Sn-like ions. 相似文献
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Network alignment (NA) is a popular research field that aims to develop algorithms for comparing networks. Applications of network alignment span many fields, from biology to social network analysis. NA comes in two forms: global network alignment (GNA), which aims to find a global similarity, and LNA, which aims to find local regions of similarity. Recently, there has been an increasing interest in introducing complex network models such as multilayer networks. Multilayer networks are common in many application scenarios, such as modelling of relations among people in a social network or representing the interplay of different molecules in a cell or different cells in the brain. Consequently, the need to introduce algorithms for the comparison of such multilayer networks, i.e., local network alignment, arises. Existing algorithms for LNA do not perform well on multilayer networks since they cannot consider inter-layer edges. Thus, we propose local alignment of multilayer networks (MultiLoAl), a novel algorithm for the local alignment of multilayer networks. We define the local alignment of multilayer networks and propose a heuristic for solving it. We present an extensive assessment indicating the strength of the algorithm. Furthermore, we implemented a synthetic multilayer network generator to build the data for the algorithm’s evaluation. 相似文献
97.
Marianna Nalli Domiziana Masci Andrea Urbani Giuseppe La Regina Romano Silvestri 《Molecules (Basel, Switzerland)》2022,27(22)
Aberrant accumulation of β-catenin in the cell nucleus as a result of deregulation of the Wnt/β-catenin pathway is found in various types of cancer. Direct β-catenin targeting agents are being researched despite obstacles; however, specific β-catenin drugs for clinical treatments have not been approved so far. We focused on direct β-catenin targeting of potential therapeutic value as anticancer agents. This review provides recent advances on small molecule β-catenin agents. Structure-activity relationships and biological activities of reported inhibitors are discussed. This work provides useful knowledge in the discovery of β-catenin agents. 相似文献
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Marianna Gniadek Elzbieta Bak Zbigniew Stojek Mikolaj Donten 《Journal of Solid State Electrochemistry》2010,14(7):1303-1310
In this work, silver and gold–polyaniline composite materials were chemically synthesized at the nitrobenzene/water interface.
Aniline (monomer) was dissolved in nitrobenzene and the oxidizing agent (either silver (I) or gold (III)) was dissolved in
water. Metals, which were formed during the reaction were in nano- and microcrystalline forms and were partially embedded
in the polymer. The forms of gold and silver crystallites found in the synthesized composites differed significantly. The
rate of growth of the PANI-Ag and -Au composites and their morphologies depended on concentration of the reagents in both
phases. The average size of the gold crystals was smaller compared to silver and was in the range of 20–25 nm. The obtained
composite materials were characterized by cyclic voltammetry, scanning electron microscopy, and Raman spectroscopy. The pernigraniline
species of polyaniline dominated in the entire volume of the PANI-Au composite and in parts of the PANI-Ag material located
at the aqueous solution side, while partially oxidized emeraldine was the main component of PANI-Ag at the organic phase side. 相似文献
100.
James M. Van Alstine Martin Malmsten Marianna M. Long Vickie King Johnson Larry J. DeLucas 《Colloids and surfaces. B, Biointerfaces》1999,14(1-4):197-211
The ability to grow quality protein crystals is necessary to analyze protein structure by X-ray diffraction and related techniques. As such it plays a key role in enzymology, structure-based drug design, molecular biology, and other biomedical areas. It is also required for macromolecule purification by crystallization. Protein crystal growth (PCG) may be negatively influenced by various factors related to nonspecific adsorption and adherence at growth chamber surfaces. Such factors include nucleation and growth of flawed crystals at chamber walls, or wall growth blockage of optical monitoring paths. Surface localized poly(ethylene glycol) (PEG) and other neutral, hydrophilic polymers are known to significantly reduce nonspecific adsorption of biological macromolecules and particles. Preliminary studies, involving various PCG methods (temperature induction, vapor diffusion), apparatii (test tubes, cuvettes, and specialized PCG hardware), growth chamber materials (glass, polystyrene, polysulfone), chamber volumes (0.1–10 ml) and protein samples (lysozyme, thaumatin, insulin) indicate the potential of PEG coatings to significantly reduce problems related to adsorption in PCG. The results, which match the ability of such coatings to reduce protein adsorption as evaluated by both ellipsometry and enzyme linked immunoassay, are discussed in relation to colloidal stabilization theory and properties of PEG coated surfaces. 相似文献