842 results match your criteria: "National Research Centre "Kurchatov Institute" 1[Affiliation]"

Transmetalation of the bis{triethylantimony(V)}-capped iron(II) tris-α-dioximate with -butylboronic acid afforded the mixed antimony, boron cross-linked clathrochelate with single reactive antimony(V)-based apical fragment. This macrobicyclic precursor easily underwent the transmetalation reactions with germanium and titanium(IV) alkoxides to give the rod-like and angular FeM-trinuclear bis-clathrochelates. Those of the aforementioned diantimony(V)-capped complex with 3- and 4-carboxyphenylboronic acids afforded the monoboron-capped iron(II) semiclathrochelates, undergoing a double-cyclization (macrobicyclization) with germanium- and titanium(IV)-based capping agents.

View Article and Find Full Text PDF

In this work, we study two series of the copolymers of L-lactide (LLA) and ε-caprolactone (CL) with the CL molar content of 5, 15, and 30 %. The first series was the commercial semicrystalline granules (Corbion, Netherlands), which we analyzed without any additional modification. The second series was amorphous films, prepared from the granules by hot pressing with the subsequent fast quenching in order to avoid the crystallization.

View Article and Find Full Text PDF

Numerous studies have shown that oxidative modifications of guanine (7,8-dihydro-8-oxoguanine, 8-oxoG) can affect cellular functions. 7,8-Dihydro-8-oxoadenine (8-oxoA) is another abundant paradigmatic ambiguous nucleobase but findings reported on the mutagenicity of 8-oxoA in bacterial and eukaryotic cells are incomplete and contradictory. Although several genotoxic studies have demonstrated the mutagenic potential of 8-oxoA in eukaryotic cells, very little biochemical and bioinformatics data about the mechanism of 8-oxoA-induced mutagenesis are available.

View Article and Find Full Text PDF

By reacting a series of 2,6-diacetylpyridine bis-hydrazones containing pyrimidine (H2L1), benzimidazole (H2L2) and phthalazine (H2L3) heterocyclic fragments with copper(II) chloride and bromide, a variety of pentacoordinated complexes of the composition , and , where X = Cl, Br, are formed. The properties and structure of the compounds were studied by means of NMR, IR, UV-vis, ESR, and X-ray absorption spectroscopy, cyclic voltammetry and X-Ray single crystal diffraction methods. It was shown that complexes of the cationic type have an asymmetric structure with a distorted square-pyramidal geometry of the coordination unit.

View Article and Find Full Text PDF
Article Synopsis
  • Recent studies suggest that there may be a connection between lysosomal storage disorders (LSDs) and symptoms of schizophrenia (SCZ), indicating that lysosomal dysfunction could play a role in SCZ development.
  • The research involved analyzing lysosomal enzyme activities and alpha-synuclein levels in blood samples from patients with late-onset SCZ and comparing them to patients with Parkinson's disease and healthy controls.
  • Significant differences were found, including decreased enzyme activity, higher concentrations of certain lysosphingolipids, and genetic variants linked to LSDs in early-onset SCZ patients, which may contribute to understanding the overlap between these conditions.
View Article and Find Full Text PDF

One of the critical stages of the T-cell immune response is the dimerization of the intramembrane domains of T-cell receptors (TCR). Structural similarities between the immunosuppressive domains of viral proteins and the transmembrane domains of TCR have led several authors to hypothesize the mechanism of immune response suppression by highly pathogenic viruses: viral proteins embed themselves in the membrane and act on the intramembrane domain of the TCRalpha subunit, hindering its functional oligomerization. It has also been suggested that this mechanism is used by influenza A virus in NS1-mediated immunosuppression.

View Article and Find Full Text PDF

Opportunities for fundamental physics research with radioactive molecules.

Rep Prog Phys

July 2024

School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, People's Republic of China.

Molecules containing short-lived, radioactive nuclei are uniquely positioned to enable a wide range of scientific discoveries in the areas of fundamental symmetries, astrophysics, nuclear structure, and chemistry. Recent advances in the ability to create, cool, and control complex molecules down to the quantum level, along with recent and upcoming advances in radioactive species production at several facilities around the world, create a compelling opportunity to coordinate and combine these efforts to bring precision measurement and control to molecules containing extreme nuclei. In this manuscript, we review the scientific case for studying radioactive molecules, discuss recent atomic, molecular, nuclear, astrophysical, and chemical advances which provide the foundation for their study, describe the facilities where these species are and will be produced, and provide an outlook for the future of this nascent field.

View Article and Find Full Text PDF

Unprecedented iron-based silsesquioxane/acetylacetonate complexes were synthesized. The intriguing cage-like structure of compounds is alkaline metal-dependent: the FeLi complex includes condensed Si-silsesquioxane and four acetylacetonate ligands; the FeNa complex exhibits two cyclic Si-silsesquioxane and eight acetylacetonate ligands, while the FeK complex features two cyclic Si-silsesquioxane and six acetylacetonate ligands. The latter case is the very first observation of small trimeric silsesquioxane ligands in the composition of cage-like metallasilsesquioxanes.

View Article and Find Full Text PDF

The North Caucasus played a key role during the ancient colonization of Eurasia and the formation of its cultural and genetic ancestry. Previous archeogenetic studies described a relative genetic and cultural continuity of ancient Caucasus societies, since the Eneolithic period. The Koban culture, which formed in the Late Bronze Age on the North Caucasian highlands, is considered as a cultural "bridge" between the ancient and modern autochthonous peoples of the Caucasus.

View Article and Find Full Text PDF

Electronic and Crystal Structure of New CrZrSe Intercalation Compounds.

Inorg Chem

January 2024

M.N. Mikheev lnstitute of Metal Physics, Ural Branch of Russian Academy of Sciences, 620137 Ekaterinburg, Russia.

New intercalation compounds CrZrSe were synthesized and thoroughly studied. Cr atoms were found to occupy the positions both tetrahedrally and octahedrally coordinated by the Se atoms in the interlayer gap. The magnetic properties and electrical resistivity were studied in the temperature ranges of 2.

View Article and Find Full Text PDF

Synthesis and properties of nano-cadmium oxide and its size-dependent responses by barley plant.

Environ Res

April 2024

Southern Federal University, ul. Bolshaya Sadovaya 105/42, Rostov-on-Don, 344006, Russia; Consortium on Health, Environment, Education, and Research (CHEER), The Education University of Hong Kong, Tai Po, Hong Kong, China.

Present study included technological methods that made it possible to synthesize CdO nanoparticles and carry out their qualitative and quantitative diagnostics, confirming the as-prepared CdO nanoparticles (NPs) were spherical and had a size of 25 nm. Then, under the conditions of the model experiment the effect of CdO in macro and nanosized particles on absorption, transformation, and structural and functional changes occurring in cells and tissues of Hordeum vulgare L. (spring barley) during its ontogenesis was analyzed.

View Article and Find Full Text PDF

The genes are present in a wide variety of conjugative plasmids and play an important role in overcoming the restriction barrier. To date, there is no information on the chromosomal genes. It is still unclear whether they keep their antirestriction activity and why bacterial chromosomes contain these genes.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on the role of satellite repeats in understanding the evolutionary relationships among grass species, specifically their contribution to the St genome in polyploid organisms.
  • A comparative analysis of the repeatomes of closely related grass species revealed similar overall structures but highlighted distinct patterns in the abundance and localization of various retrotransposons and satellite repeats.
  • The findings suggest that the analyzed species share a close evolutionary relationship, and the newly identified chromosome markers can aid in future population studies involving related wild species and hybrid forms.
View Article and Find Full Text PDF

Ribosome is a major part of the protein synthesis machinery, and analysis of its structure is of paramount importance. However, the structure of ribosomes from only a limited number of organisms has been resolved to date; it especially concerns plant ribosomes and ribosomal subunits. Here, we report a high-resolution cryo-electron microscopy reconstruction of the small subunit of the (common wheat) cytoplasmic ribosome.

View Article and Find Full Text PDF

Currently, there is great interest in the development of highly sensitive bioanalytical systems for diagnosing diseases at an early stage, when pathological biomarkers are present in biological fluids at low concentrations and there are no clinical manifestations. A promising direction is the use of molecular detectors-highly sensitive devices that detect signals from single biomacromolecules. A typical detector in this class is the atomic force microscope (AFM).

View Article and Find Full Text PDF

Relativistic coupled-cluster calculations of the ionization potential, dissociation energy, and excited electronic states under 35 000 cm-1 are presented for the actinium monofluoride (AcF) molecule. The ionization potential is calculated to be IPe = 48 866 cm-1, and the ground state is confirmed to be a closed-shell singlet and thus strongly sensitive to the T,P-violating nuclear Schiff moment of the Ac nucleus. Radiative properties and transition dipole moments from the ground state are identified for several excited states, achieving a mean uncertainty estimate of ∼450 cm-1 for the excitation energies.

View Article and Find Full Text PDF

In this work, a stochastic model of gaseous transfer in polymer-carbon-nanotube (CNT) nanocomposites is presented. The model takes into account interfacial areas, i.e.

View Article and Find Full Text PDF

Herein, neptunium(V) carbonates containing sodium or potassium cations were synthesized via chemical precipitation. Various techniques such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetry combined with differential scanning calorimetry, X-ray diffraction, and X-ray absorption spectroscopy were used to analyze the microstructures and elemental compositions of these samples. The crystal structures of hydrated NaNpOCO·3HO (1, = 4.

View Article and Find Full Text PDF

Parkinson's disease (PD) is a common chronic, age-related neurodegenerative disease. This disease is characterized by a long prodromal period. In this context, it is important to search for the genes and mechanisms that are involved in the development of the pathological process in the earliest stages of the disease.

View Article and Find Full Text PDF

An electrochemical hydrogen pump (EHP) with a proton exchange membrane (PEM) used as part of fusion cycle systems successfully combines the processes of hydrogen extraction, purification and compression in a single device. This work comprises a novel study of the effect of ionizing radiation on the properties of the PEM as part of the EHP. Radiation exposure leads to nonspecific degradation of membranes, changes in their structure, and destruction of side and matrix chains.

View Article and Find Full Text PDF

A novel neutral tetranitrosyl iron complex {[Fe(HO)][FeR(NO)]}·4HO (1) with R = 5-(3-pyridyl)-4-1,2,4-triazole-3-thiolyls (CHNS), which is a supramolecular ensemble, has been synthesized and studied. As follows from X-ray diffraction analysis, this is an octahedral Fecomplex (Lewis acid) with two monoanionic dinitrosyl groups [FeR(NO)] (Lewis base) and 4 water molecules as the ligands. As follows from Mössbauer spectra, the coordinating Fe ion is in a low-spin state = 0, and the dinitrosyl Fe ion is in a low-spin state = 1/2.

View Article and Find Full Text PDF

Separation of metric in Wick's theorem.

J Chem Phys

November 2023

National Research Center "Kurchatov Institute," Kurchatov Sq. 1, Moscow 123182, Russia.

In quantum chemistry, Wick's theorem is an important tool to reduce products of fermionic creation and annihilation operators. It is especially useful in computations employing reference states. The original theorem has been generalized to tackle multiconfigurational wave functions or nonorthogonal orbitals.

View Article and Find Full Text PDF

Photosystem II for photoelectrochemical hydrogen production.

Biophys Rev

October 2023

Federal Research Center "Pushchino's center of Biological Research, of Basic Biological Problems of Russian Academy of Sciences, Institutskaya st 2, Moscow, 142290 Russia.

Unlabelled: Water is a primary source of electrons and protons for photosynthetic organisms. For the production of hydrogen through the process of mimicking natural photosynthesis, photosystem II (PSII)-based hybrid photosynthetic systems have been created, both with and without an external voltage source. In the past 30 years, various PSII immobilization techniques have been proposed, and redox polymers have been created for charge transfer from PSII.

View Article and Find Full Text PDF

Neutrinoless double beta decay (0νββ) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νββ) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νββ decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.

View Article and Find Full Text PDF

The anaerobic oxidation of fatty acids and alcohols occurs near the thermodynamic limit of life. This process is driven by syntrophic bacteria that oxidize fatty acids and/or alcohols, their syntrophic partners that consume the products of this oxidation, and the pathways for interspecies electron exchange via these products or direct interspecies electron transfer (DIET). Due to the interdependence of syntrophic microorganisms on each other's metabolic activity, their isolation in pure cultures is almost impossible.

View Article and Find Full Text PDF