1,543 results match your criteria: "Universitetskaya Nab[Affiliation]"

Currently, the TAAR1 receptor has been identified in various cell groups in the intestinal wall. It recognizes biogenic amine compounds like phenylethylamine or tyramine, which are products of decarboxylation of phenylalanine and tyrosine by endogenous or bacterial decarboxylases. Since several gut bacteria produce these amines, TAAR1 is suggested to be involved in the interaction between the host and gut microbiota.

View Article and Find Full Text PDF

To prepare novel biodegradable copolymers with functional substituents that are distributed statistically or randomly over the macromolecule chain and have improved characteristics compared to homopolymers, we conducted a series of synthetic experiments with a novel cyclic monomer, 5-(benzyloxy)-1,3-dioxepan-2-one (). This compound was synthesized, and its homopolymer, as well as its copolymers with L-lactide, ε-caprolactone and trimethylene carbonate, were prepared in a polymerization solution with stannous octoate as the initiator. The formation of the copolymers was confirmed using NMR spectroscopy and DSC data.

View Article and Find Full Text PDF

Segmented polymers, such as polyether block amide (PEBA), exhibit unique properties due to the combination of different segments. PEBA consists of soft polyester and rigid polyamide blocks, enabling its use in various industrial applications, including membrane technologies. In this study, PEBA membranes modified with a holmium-based metal-organic framework (Ho-1,3,5-Hbtc) were developed for enhanced pervaporation separation of water/isopropanol and water/phenol mixtures.

View Article and Find Full Text PDF

Monoamine oxidase (MAO) plays a key role in the pathogenesis of central nervous system disorders, and MAO inhibitors have been used in the treatment of depression and Parkinson's disease. In the search for new classes of MAO inhibitors, the present study investigated a series of 1,2,4-oxadiazin-5(6)-one derivatives. This study provides the first optimization of the reaction conditions for the condensation of amidoximes with alkyl 2-halocarboxylates to yield the desired 1,2,4-oxadiazin-5(6)-ones.

View Article and Find Full Text PDF

In this work, a set of analytical techniques, including scanning electron microscopy (SEM), Raman scattering spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray microanalysis (EDX) and cyclic voltammetry (CV), were used to study the impact of high-energy He ion irradiation on the structural and electrochemical characteristics of sulfur-containing multi-walled carbon nanotubes (S-MWCNTs) placed on a titanium substrate. The results indicate that the ion beam treatment of the S-MWCNT system led to an increase in the level of imperfections on the surface structures of the nanotubes due to the formation of point defects on their outer walls and the appearance of oxygen-containing functional groups, including SO groups, near these defects. At the same time, a significant increase in the sulfur concentration (by 6.

View Article and Find Full Text PDF

The oxygen reduction reaction (ORR) plays a central role in energy conversion and storage technologies. A promising alternative to precious metal catalysts are non-precious metal doped carbons. Considerable efforts have been devoted to cobalt-doped carbonized polyacrylonitrile catalysts, but the optimization of their catalytic performance remains a key challenge.

View Article and Find Full Text PDF

3D-printed microporous titanium scaffolds enjoy good biointegration with the residuum's soft and bone tissues, and they promote excellent biomechanical properties in attached prostheses. Implant-associated infection, however, remains a major clinical challenge. Silver-based implant coatings can potentially reduce bacterial growth and inhibit biofilm formation, thereby reducing the risk of periprosthetic infections.

View Article and Find Full Text PDF

Cocrystallization of CuI with NCNMe in the presence of substituted perfluoroarenes─iodoperfluorobenzene (IFB), 4,4'-diiodoperfluorobiphenyl (4,4'-FIBP), and 4-bromoperfluorobenzonitrile (4-BrFBN)─led to the formation of three types of adducts ·2(IFB), ·4,4'FIBP, and ·4-BrFBN ( is CuI(NCNMe)), all studied by X-ray crystallography. In these cocrystals, the coordinated nitrile N atom (whose electron pair is engaged in metal coordination) still acts as an electron donor, forming π-hole interactions, specifically, π-hole···N, with the perfluoroarenes. These interactions were examined in the context of their occurrence alongside other interactions involving C atoms of the electron-deficient aromatic rings and nucleophilic atoms of the copper cluster.

View Article and Find Full Text PDF

Although lithium salts are the most successful materials for electrochemical devices so far, there is growing interest in electrolytes containing divalent and trivalent salts, which are characterized by a much higher energy density than lithium systems. For this purpose, the physical and chemical properties of solutions of aluminum nitrate in ethylammonium nitrate (EAN) were studied in a number of works. However, it was demonstrated by the H NMR method that solutions contain water (from aluminum crystallohydrates) in the first solvated shell of the Al cation even after usual drying procedures, and this solvated water cannot be directly detected by the standard Karl Fischer analysis.

View Article and Find Full Text PDF

New data on the Palaearctic subgenus Holoclera Schiner of dance flies of the genus Rhamphomyia Meigen (Diptera: Empididae) are reported. Three new species are described: Rhamphomyia (Holoclera) richterae sp. nov.

View Article and Find Full Text PDF

We provide the first diversity assessment of Iranian species of the genus Asaccus based on COI DNA-barcoding. We analyzed 53 samples of Iranian Asaccus representing nine OTU corresponding to 10 currently recognzied nominal species, and evaluated both morphological and genetic data to support the recognition of a new species from Bandar-e Jask, Hormozgan Province, southern Iran-Asaccus authenticus sp. nov.

View Article and Find Full Text PDF

Redescription of the holotype of the cane toad Rana marina Linnaeus, 1758 (Anura: Bufonidae).

Zootaxa

May 2024

Laboratório de Herpetologia e Comportamento Animal; Departamento de Ecologia; Instituto de Ciências Biológicas; Universidade Federal de Goiás; 74690-900 Goiânia; GO; Brazil.

View Article and Find Full Text PDF

Available information about bees of the genus Epeolus (Hymenoptera: Apidae) in the Palaearctic region is summarized. Forty-eight species are currently known from this area. A new synonymy is proposed for Epeolus tsushimensis Cockerell, 1926=E.

View Article and Find Full Text PDF

Four species of the polyplacophoran genus Cryptoplax were identified among chiton samples collected from the Spratly Islands (Truong Sa), South China Sea. Among them, one is described as new species C. acerocostata n.

View Article and Find Full Text PDF

The type specimens for names of bee taxa in the subfamily Panurginae of family Andrenidae deposited in the Zoological Institute, Russian Academy of Sciences (St. Petersburg) are reviewed. Primary types of 39 taxa are illustrated and detailed information is provided (taxa include 19 described by F.

View Article and Find Full Text PDF

Distribution of Phoenicurusia transcaucasicus (Miller, 1923) in Iran and neighbouring territories is clarified based on analysis of DNA barcodes, the male genitalia and wing pattern of adults. Our study revealed the widespread distribution of Ph. transcaucasicus throughout northern, northeastern and central Iran.

View Article and Find Full Text PDF

Polymer Electrolytes for Supercapacitors.

Polymers (Basel)

November 2024

Confucius Energy Storage Lab, School of Energy and Environment, Southeast University, Nanjing 210096, China.

Because of safety concerns associated with the use of liquid electrolytes and electrolyte solutions, options for non-liquid materials like gels and polymers to be used as ion-conducting electrolytes have been explored intensely, and they attract steadily growing interest from researchers. The low ionic conductivity of most hard and soft solid materials was initially too low for practical applications in supercapacitors, which require low internal resistance of a device and, consequently, highly conducting materials. Even if an additional separator may not be needed when the solid electrolyte already ensures reliable separation of the electrodes, the electrolytes prepared as films or membranes as thin as practically acceptable, resistance may still be too high even today.

View Article and Find Full Text PDF

NMR Relaxation to Probe Zeolites: Mobility of Adsorbed Molecules, Surface Acidity, Pore Size Distribution and Connectivity.

Molecules

November 2024

Department of Nuclear Physics Research Methods, Saint Petersburg State University, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia.

Unique structural and chemical properties, such as ion exchange, developed inner surface, etc., as well as the wide possibilities and flexibility of regulating these properties, cause a keen interest in zeolites. They are widely used in industry as molecular sieves, ion exchangers and catalysts.

View Article and Find Full Text PDF

Background/objectives: Cervical cancer (CC) remains a significant global health challenge, characterized by genetic heterogeneity and a complex molecular landscape, both of which contribute to its pathogenesis. This study aimed to investigate germline variants in proto-oncogenes and tumor suppressor genes in cervical cancer patients, with the objective of clarifying their potential role in disease development.

Methods: We utilized a custom next-generation sequencing (NGS) panel targeting 48 genes implicated in oncogenesis.

View Article and Find Full Text PDF