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The first comprehensive structural and extraction study of a 2,2'-bipyridine-6,6'-dicarboxamide (

Magnetic nanoparticles are widely used in medical applications, for example, as contrast agents for magnetic resonance imaging, to enhance hyperthermia, for targeted drug delivery, theranostics (therapy + diagnostics). When used in vivo, magnetic nanoparticles require a special coating that promotes biocompatibility and minimizes potential toxicity under physiological conditions. Human serum albumin or polyethylene glycol can be used as a coating. In this work, the interactions of magnetic cobalt ferrite nanoparticles (12 and 27 nm size) with diphitanoylphosphatidylcholine bilayer lipid membranes were investigated. The conductivity of membranes varied over a wide range – two groups of membranes can be distinguished – membranes, the conductivity of which (after the addition of nanoparticles) remained practically unchanged compared to the control, and membranes, the conductivity of which, upon the addition of nanoparticles, changed abruptly and increased in a wide range by 0.5–2 orders of magnitude. Significant differences between the conductivities upon the addition of the same volume of 12 and 27 nm nanoparticles surrounded by human serum albumin were not found. When adding nanoparticles with a coating of polyethylene glycol, the conductivity increased much weaker than when adding nanoparticles with a coating of human serum albumin. The results suggest that hydrophilic coated magnetic nanoparticles interact with the membranes, which can lead to the appearance of metastable conducting pores, which, in turn, increase the integral conductivity of the membranes.

The article contains the features of regional strategic planning in the context of the implementation of the national priority — people-saving. The purpose of the study is to determine the key vector of regional strategic planning, taking into account current trends and realities of the pandemic. The study is based on official data from the Federal State Statistics Service. The basis of the research methodology is a logical-epistemological toolkit with a linkage of general scientific methods of comparison and correlation analysis. It was found that the mortality rate of the population is of critical importance in achieving national strategic priorities. And, consequently, the identification of factors of an increased mortality rate is a priority analytical task in the implementation of a regional strategy of socio-economic development. The results of the studies carried out provide the initial basis for the development of municipal strategies. In order to concretize targeted management decisions, it is further necessary to determine the relationship between mortality from specific diseases and the availability of doctors in the relevant specialties, with access to the schemes of targeted training of doctors for municipalities. More ambitious further tasks — to identify factors and assess the strength of their influence on the mortality of the population; to create an integrated model using Data Mining tools, which provides support for making management decisions aimed at reducing mortality in the region.

Modern democratic procedures do not meet the needs of society. The authorities are not interested in attracting citizens to participate in the management of state affairs, preferring to give them only the authority to form them. The indifference of citizens leads to an authoritarian style of government, which negatively affects the political climate in the state. A number of political scientists and philosophers believe that the problem of society's detachment from making political decisions can be solved by a deliberative form of democracy, in which citizens are given maximum freedom to discuss and make political decisions. The study identifies the features of deliberative democracy and draws conclusions about its pros and cons in modern realities.

Hybrid donor extractants are a promising class of compounds for the separation of trivalent actinides and lanthanides. In this paper, we present a new ligand from the bipyridyl-dicarboxylic acid diamide family—N,N’-diethyl-N,N’-bis(2,4,5-trimethylphenyl)-[2,2’-bipyridine]-6,6’-dicarboxamide. The synthesis of N-ethyl-2,4,5-trimethylaniline from pseudocumene by selective acetylation is presented. The target ligand was obtained using this aminylene. Chemical synthesis of its complexes with Ln(NO3)3 and their spectroscopic analysis showed that the structure of the complexes is near to the corresponding structures of well-known di-methylated dianilides. A series of studies on the photophysical, complexing, and extraction properties of this ligand and its complexes were carried out. It was shown that the extraction system based on this ligand can selectively isolate americium from the solution of high-level waste imitator.

The fractionation of high-level radioactive waste from nuclear power plants simplifies the handling of its components, and facilitates the reduction of radiotoxic effects on the environment. The search and study of new ligands for solvent extraction, as one of the methods in fractionation, remains a complex and important research task. In this work, four pyridine diphosphonate ligands were synthesized. These ligands are part of the class of the N,O-donor extractants, which are selective towards Am(III). The separation factor SF(Am/Eu) for the best extractant reached values up to 10. The influence of the substituents on the efficiency of extraction and complexation of trivalent f-elements, the kinetics of extraction, and the behavior of the ligand at the interface were described. The effect of nitric acid concentration on the extraction was shown. The stoichiometry of the complexes was determined by slope analysis in solvent extraction experiment and verified by spectrophotometric titration in acetonitrile. Liquid tension experiments with a pendant drop method revealed the interfacial properties of the ligands in "F-3 solvent/H

Extraction of lanthanides and actinides from nitric acid solutions with N-(diphenylphosphoryl)-N'-n-propylureas containing imidazolyl, diethylamino, pyrid-2-yl, 2-oxopyrrolidino fragments in the ω position of the alkyl substituent has been studied. It has been shown that Ho(III) and Yb(III) related to the yttrium subgroup of lanthanides are extracted much better than La(III) and Nd(III) related to the cerium subgroup. N-(Diphenylphosphoryl)urea containing ω-(2-oxopyrrolidino)propyl fragment at the terminal nitrogen atom shows the best extraction properties. This dependence has been theoretically explained by modeling complexation because the coordination of f-block element ion with amide oxygen atom is more preferable

Cancerous and precancerous skin conditions occupy one of the leading places in oncology. Early detection of suspects and temporary referrals to a specialist are critical to successful treatment. Numerous optical techniques are used for obtaining a new data from cutaneous neoplasia. Diffuse–reflectance spectroscopy is one of these techniques due to its high sensitivity in detecting subtle tissue alterations. Light scattering events inside the skin tissues change significantly in the development stage of skin lesions. These changes in the tissue scattering properties affect the diffuse reflectance spectrum and provide classification of different skin lesions based on diffuse reflectance measurements. We have investigated diffuse–reflectance spectroscopy for diagnostic of skin lesions and as a result, an optical device for clinical application was developed. The current study shows the obtained results by the prototype device for the reflective ability of pigmented and non-pigmented skin benign, dysplastic, and malignant cutaneous lesions in vivo.

Glioblastoma (GBM) is the most common and severe type of brain tumor. Surgery and subsequent radiotherapy and chemotherapy do not lead to sufficient results in the treatment of this type of malignancy, mostly due to its specific morphology. Only about 6% of the patients of advanced age survive 5 years after being diagnosed with GBM. Therefore, scientists are working on alternative therapies that would lead to more effective and long-term treatment of glioblastoma. Photodynamic therapy (PDT) and photodiagnostics (PD) are such unconventional methods for treating and diagnosing malignant tumors. During our work, more than 20 experiments were carried out with stem cells cultivated from human glioblastoma tumors. We used two types of photosensitizers – delta-aminolevulinic acid (5-ALA) as a precursor of protoporphyrin IX (PpIX) and non-peripherally galactosylated lutetium phthalocyanine (n-GalLuPc). After the irradiation supernatant samples of photosensitizer-treated cell lines were used for evaluation of photosensitizers’ accumulation in the cell lines investigated. The emitting spectra is correlated with the total induced cell death in the treated cells. After considering the overall effectiveness of the two photosensitizers, n-GalLuPc showed higher efficiency. These in vitro results prompted the future investigation of the phthalocyanine for in vivo application in GBM treatments.

The reaction of P,S-phosphoramidite bearing (Ra)-BIPHEN H2 core and exocyclic amino sulfide as the new ligand with [Pd(ppp-allyl)Cl]2 in the presence of AgBF4 yielded a cationic metallochelate [Pd(ppp-allyl)(L)]BF4. This new chiral inducer provided up to 90% ee in the Pd-mediated allylic substitution reaction of (E)-1,3-diphenylallyl acetate with various C- and N-nucleophiles. In the Pd-catalyzed amination of 2-diethoxyphosphoryl-1-phenylallyl acetate with aniline, ee values up to 57% were achieved.

В обзоре представлена методика исследования средств создания образа персонажа в художественном тексте и его экранизации. Последняя рассматривается как поликодовый текст, к которому применяется метод общефилологического анализа. Изучение проводится на материале сказки Роальда Даля «Матильда» на языке оригинала.

In this work, we studied the thermodynamic parameters of the complexation reaction between europium and N,N '-diethyl-N,N '-difluorophenyl-2,2'-bipyridyl-6,6'-dicarboxamides in ethanol. The complexation reaction lead to one complex particle with 1 : 1 metal : ligand composition. Spectrophotometric and calorimetric titration methods were used for determination of the stability of complexes. According to our data, the fluorine atom in the meta-position in the ligand (log K = 3.59) increases the stability of complexes, enthalpy and entropy compared with the para-position (log K = 3.26). Comparison of two parameters ΔrH and TΔrS for the 3-F ligand (–8.6 and 14.15 kJ/mol, respectively) shows that they are lower than that of for the 4-F ligand (–15.5 and 10.19 kJ/mol, respectively).

This study clarifies the essence of communicative provocation with elements of verbal aggression manifesting in the way internet bloggers behave if conflict situations arise between them and traffic patrol officers of the State Inspectorate for Road Traffic Safety. The specifics of communicative provocation is analyzed from the psychological and legal perspective and on the basis of video recordings of direct communication between road users and traffic patrol officers. We describe the tactics of bloggers' conflict verbal behavior and also the psychological makeup of traffic patrol officers as the target of communicative provocation. Suggestions of psychological and legal significance are formulated with the view of: 1) relaxing the conflict potential of the situations under consideration; 2) strengthening the skills of traffic patrol officers of the State Inspectorate for Road Traffic Safety; 3) improvement of their professional performance.

Along with bright fluorescence in the near-IR range, heptamethine carbocyanine dyes possess affinity to cancer cells. Thus, these dyes could be utilized as fluorescent labels and vectors for drug delivery as covalent conjugates with cytotoxic compounds. To test the properties, structure-activity relationship, and scope of such conjugates, we synthesized drug-dye dyads of tricarbocyanine dyes with anthracycline drug daunorubicin. We used hydrophilic zwitterionic and hydrophobic positively charged benzoindoline-benzothiazole-based heptamethine dyes as terminal alkyne derivatives and N-acylated or oxime-linked daunorubicin as azido-derivatives. These two alkynes and two azides were coupled to each other by Cu-catalyzed Huisgen-Meldal-Sharpless cycloaddition (click reaction) to afford four conjugates. Molecules based on hydrophobic dyes possess submicromolar cytotoxicity to HCT116 cells. Cytotoxicity, cell penetration, intracellular distribution, apoptosis induction and the effect of antioxidants on toxicity were evaluated. The results show that the structure of the cyanine-anthracycline conjugate (hydrophilicity/hydrophobicity, charge, linker, attachment site) is important for its biological activity, thus, expansion of the chemical space of such conjugates could provide new molecular research tools for diagnostics and therapy.

Purpose – Transformations of natural reservoirs of the state reserve “Voroninsky” are considered in order to obtain criteria for identifying the direction of anthropogenic changes in the ecological state of surface waters. Materials and methods. When assessing the ecological state of water bodies, methods of calculating the saprobity index and comparing the taxonomic composition of the phytoplankton community were used. Results and discussion. Global climatic changes are manifested in the shallowing and overgrowing of water bodies, in an increase in the volume of organic matter formed in bottom sediments. The formation of new biotopes is taking place, and the taxonomic and ecological composition of communities of microalgae and cyanobacteria is transformed accordingly. The influence of air temperature anomalies in 2010-2012 manifested itself in the invasion of the reserve's lakes and the mass development of thermophilic cyanobacteria species alien to the region. There is no “blooming” of water bodies due to the equilibrium state of the processes of formation, accumulation and mineralization of organic matter. The Voronezh Reservoir is a water body located in an anthropogenically loaded territory. “Bloom” of waters, represented by cyanobacteria of the genus Microcystis (Ku & & tz. ) Elenk. The temperature stress of 2010-2012 found a response in the ecological state of the reservoir: the “bloom” of water in 2013-2020 gained a greater areal distribution over the water area, and became more prolonged during the growing season, recorded practically from June to October. The general tendency in the formation of the ecological quality of waters is associated with their widespread pollution, including those caused by the proliferation of cyanobacterial species, which often release cyanotoxins in the process of metabolism. Conclusions. The forecast of transformation of surface water quality is unfavorable and emphasizes the severity of the current ecological situation.

Proportional electroluminescence in noble gases is used in two-phase detectors for dark-matter searches for detecting ionization signals in a liquid phase (S2 signals). Time features of electroluminescence signals in a two-phase argon detector were studied systematically both over a broad range of reduced electric fields—from 3 to 9 Td (Townsend)—and for various methods of optical readout in different spectral ranges—by means of cryogenic photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs), with a wavelength shifter and without it, in vacuum ultraviolet and visible ranges. Both a fast and a slow component of signals were observed. An observation of an unusual long component of the S2 signal is described in the present article. This component has a time constant of about 40 $$\mu$$ s, which grows with increasing electric field, and can not be explained in terms of known scintillation mechanisms. Also, it is shown here that the fast component can be used to measure the thickness of the electroluminescence gap to a submillimeter precision. The results obtained in these experiments may find practical applications in the DarkSide experiment devoted to searches for dark matter.

Two-phase noble liquid detectors are widely used in experiments for dark matter search. Ionization signals caused by particle scattering in a noble-gas liquid are commonly recorded using the effect of proportional electroluminescence in the gas phase. In addition to the standard electroluminescence mechanism based on vacuum ultraviolet emission of noble gas excimers, the mechanism of electron bremsstrahlung on neutral atoms with a continuous spectrum from ultraviolet to near infrared range was recently revealed. In this paper, we demonstrate the effect of bremsstrahlung on characteristics of a DarkSide-50 two-phase argon detector. In particular, the sag of the electroluminescent gap grid and the contribution of the fast component to the proportional electroluminescence signal will be estimated.

The molecular mobility of poly(4,4'-bis(4-aminophenoxy)biphenyl)imido-1,3-bis(3,3'-4,4'-dicarboxyphenoxy)benzene) films is studied by the thermally stimulated depolarization current (TSDC) technique and dielectric spectroscopy. The existence of two dipolar polarization relaxation regions (β and α) related to the local mobility in the glassy state and the cooperative segmental mobility in the rubbery state, respectively, is revealed. The temperature dependences of the relaxation time for the β-process obey the Arrhenius equation; for the α-process, they obey the Vogel–Tammann–Hesse equation. Emergence of the third peak βI is related to relaxation of the space homocharge. The molecular mechanisms of all the observed processes are revealed.

The interactions of one of the most famous enzymes, lysozyme, with carboxylated nanodiamonds in water were studied. It was found that stable complexes are formed as a result of lysozyme adsorption ...

Novel near IR absorbing zinc 2,3-naphthalocyanine with bulky 2-naphthyl groups was obtained from corresponding 2,3-dicyanonaphthalene and characterized by mass spectrometry, UV-Vis, infrared and nuclear magnetic resonance spectroscopy (NMR). Two-dimensional NMR was employed for full proton and carbon signal assignment in initial 2-naphthyl-substituted 2,3-dicyanonaphthalene. The main absorption maximum of 2-naphthyl-substituted naphthalocyanine complex at 790 nm shows a shift of 6 nm to the near IR region compared to phenyl-substituted analogues. The UV-Vis spectrum of the complex in o-DCB shows strong aggregation, which can be suppressed by N-containing agents or ternary ammonium salt due to steric hindrance or electrostatic repulsion. Pyridine demonstrates the most pronounced effect that reaches maximum value at 2 vol% pyridine. The monomeric form of the naphthalocyanine complex has a narrow Q band and well-resolved satellites. Since pyridine may play a role of both coordinating and reducing agent, fluorescence and electron paramagnetic resonance spectroscopy were used to clarify the mechanism of its influence on the naphthalocyanine complex. Fluorescence properties (fluorescence and excitation spectra, fluorescence quantum yield) as well as electrochemical and spectroelectrochemical behavior were studied in o-DCB. The addition of pyridine results in a slight shift towards a higher value for the first oxidation and first reduction potentials. Moreover, the first oxidation process shows a split that increases after the addition of pyridine. Nevertheless, a single reversible one-electron transition was confirmed by spectroelectrochemical titration in the region of the first oxidation. The first oxidation process of the naphthalocyanine complex was accompanied by reversible color change from olive to bright green, which is not typical for naphthalocyanine complexes with other functional groups (e.g. unsubstituted, alkyl).

This paper discusses the electrical conductivity of chitosan-based film matrices, as well as optimization of these properties by adding chitin nanofibrils. It has been shown that the filler addition increase the conductivity of the composite material. By changing the concentration of chitin nanofibrils, it is possible to obtain matrices with different bioactive properties for cultured human dermal fibroblasts. The optimal balance of electrical conductivity and bioactivity in relation to the culture of human dermal fibroblasts is possessed by film matrices based on chitosan nanocomposite with the addition of 5% chitin nanofibrils. Film matrices based on chitosan nanocomposite with the addition of 5% chitin nanofibrils provide the optimal balance of conductivity and bioactivity for cultured human dermal fibroblasts.

In the present communication, we uncovered the aqueous phase Fischer-Tropsch reaction over rhodium catalysts. The reaction results in the synthesis and consecutive separation of hydrocarbons and oxygenates into two phases. Use of a rhodium Schiff base complex as a precursor for catalyst preparation allows efficient control of the Rh metal nanoparticle size distribution and leads to higher alcohol selectivity.

In liquid argon TPCs for dark matter search and neutrino detection experiments, primary scintillation light is used as a prompt signal of particle scattering, being intensively produced in the vacuum ultraviolet (VUV) due to excimer emission mechanism. On the other hand, there were indications on the production of visible-light emission in liquid argon, albeit at a much lower intensity, the origin of which is still not clear. The closely related issue is visible-light emission in liquid argon doped with methane, the interest in which is due to the possible use in neutron veto detectors for those experiments. In this work we study in detail the properties of such light emission in pure liquid argon and its mixtures with methane. In particular, the absolute photon yield of visible-light emission in pure liquid argon was measured to be about 200 and 90 photon/MeV for X-rays and alpha particles respectively. In liquid argon doped with methane the photon yield dropped down significantly, by about an order of magnitude at a methane molar content varying from 0.01 to 1%, and then almost did not change when further increasing the methane content up to 10%., 22 pages, 15 figures, 3 tables