Novosibirsk State University

Background Epidemiologically important food-borne trematodes Opisthorchis viverrini and Clonorchis sinensis are recognized as biological carcinogens of Group 1A, while Opisthorchis felineus is in Group 3 as noncarcinogenic to humans. Mechanisms of the biological carcinogenesis are still elusive. Some studies highlight chronic inflammation as a key factor and common pathway for cancer initiation and progression. Nonetheless, the chronic inflammation alone does not explain why these three species differ in carcinogenicity. We focused this study on genome-wide landscapes of liver gene expression and activation of cellular pathways in Mesocricetus auratus golden hamsters infected with C. sinensis (South Korea), O. viverrini (Thailand), or O. felineus (Russia) at 1 and 3 months after infection initiation. Methodology/Principal findings Liver transcriptomes of golden hamsters (HiSeq Illumina, 2X150 bp) were sequenced at 1 and 3 months postinfection. Data processing was carried out using the following bioinformatic and experimental approaches: analysis of differential gene expression, estimates of proportions of affected liver cell types, liver histopathology, and examination of weighted gene coexpression networks. All infections caused enrichment with inflammatory response signaling pathways, fibrogenesis and cell proliferation, and IL2–STAT5, TNF–NF-κB, TGF-β, Hippo, MAPK, and PI3K–Akt signaling pathways. Nevertheless, species-specific responses to each infection were noted too. We also identified species-specific responses of liver cell types, differentially expressed gene clusters, and cellular pathways associated with structural liver damage (such as periductal fibrosis, epithelial neoplasia, and inflammation). Conclusions/Significance This is the first comparative analysis of gene expression landscapes in the liver of experimental animals infected with O. viverrini, O. felineus, or C. sinensis. The trematodes have species-specific effects on the hepatobiliary system by triggering signaling pathways, thereby leading to differences in the severity of hepatobiliary structural lesions and contributing to the pathogenicity of closely related foodborne trematodes.

Two series of new thiacarbocyanines with iodine atoms in the donor and/or acceptor block have been synthesized. The absorption spectra of the iodinated dyes in the region of singlet-singlet S0-S1 and singlet-triplet S0-T1 transitions are investigated. The introduction of iodine atoms into the dye structures leads to a red shift of the absorption maximum, regardless of the position of iodine in the molecule. For dyes with two or more iodine atoms, a low-intensity long-wave absorption shoulder in the region from 650 to 1000 nm is detected, which corresponds to singlet-triplet absorption.

Acid-catalyzed carbonylation of a number of polyfluorinated benzocyclobuten-1-ols, as well as cyclic sulfoesters of benzocyclobuten-1,2-diols, in reaction with carbon monoxide has been carried out. The efficiency of using TfOH and FSO3H-SbF5 as acidic systems was evaluated. Both products of CO addition with the remaining four-membered ring — the corresponding carboxylic acids, and various products of carbonylation accompanied by its transformations (ring opening, opening followed by heterocyclization with the formation of isochromane derivatives, expansion to a five-membered one) were obtained. In some cases, the formation of polycyclic dimeric products was also observed.

The development of quantum bits (qubits) is crucial for the progress of quantum technologies. Among various approaches, the qubits based on paramagnetic centers have decent advantages, including their diversity and possibilities of regular ordering, for example, within the structure of metal-organic frameworks (MOFs). In the present work a simple and scalable approach to obtain qubit candidates based on stable organic radical 3-carboxy-proxyl and MOF-808 framework has been demonstrated. Investigation of the obtained compounds with different radical amounts using electron paramagnetic resonance (EPR) demonstrates the presence of two fractions of radicals, which is supported by simulations. Sufficiently long phase memory time at room temperature for the radicals adsorbed into MOF (0.39 μs), as well as the observed Rabi nutations, allow considering this material as a platform for qubits design. The developed approach is capable of incorporating various amounts of paramagnetic centers into the MOF structure and can be employed to obtain other spin qubit candidates.

The development of quantum bits (qubits) is crucial for the progress of quantum technologies. Among various approaches, the qubits based on paramagnetic centers have decent advantages, including their diversity and possibilities of regular ordering, for example, within the structure of metal-organic frameworks (MOFs). In the present work a simple and scalable approach to obtain qubit candidates based on stable organic radical 3-carboxy-proxyl and MOF-808 framework has been demonstrated. Investigation of the obtained compounds with different radical amounts using electron paramagnetic resonance (EPR) demonstrates the presence of two fractions of radicals, which is supported by simulations. Sufficiently long phase memory time at room temperature for the radicals adsorbed into MOF (0.39 μs), as well as the observed Rabi nutations, allow considering this material as a platform for qubits design. The developed approach is capable of incorporating various amounts of paramagnetic centers into the MOF structure and can be employed to obtain other spin qubit candidates.

The reactions of cobalt(II) nitrate with 4,7-di(1,2,4-triazol-1-yl)-2,1,3-benzothiadiazole (Tr2btd) and aromatic dicarboxylic acids (terephthalic (H2bdc), 2,6-naphthalenedicarboxylic (2,6-H2Ndc), and 2,5-furandicarboxylic (2,5-H2Fdc) acids) afford metal-organic frameworks [Co(Tr2btd)(bdc)]n (I) and {[Co2(Tr2btd)(Dmf)(2,6-Ndc)2]·Dmf}n (II) with the layered structures and chain metal-organic framework [Co(Tr2btd)2(H2O)(2,5-Fdc)]n (III). Compounds I and III are paramagnetic in a temperature range of 1.77–300 K without exchange interactions between the Co2+ cations, and compound II exhibits the antiferromagnetic interaction between the Co2+ cations in the binuclear building blocks with the exchange interaction constant J ≈ −100 K. Single crystals of the phase of compound IIIa with the identical composition but different structure are found when taking samples for X-ray diffraction (XRD) analysis. The molecular structures of metal-organic frameworks I, II, III, and IIIa are determined by XRD (CIF files CCDC nos. 2343141 (I), 2343297 (II), 2343296 (III), and 2343140 (IIIa)).

Signal amplification by reversible exchange (SABRE) employs the non-equilibrium spin order of parahydrogen as a source of strong nuclear magnetic resonance (NMR) signal enhancement, with the objective of increasing NMR sensitivity. In SABRE, a parahydrogen molecule and a substrate form a transient polarization transfer complex. Performed within the high magnetic field of an NMR spectrometer, SABRE enables the hyperpolarization of nuclear spins without additional polarizers. Nevertheless, it requires thorough pulse sequence design. The high-field polarization transfer strategy strongly depends on the type of the spin system formed by the parahydrogen-nascent protons in the SABRE complex: chemically equivalent or non-equivalent. SABRE hyperpolarization in chemically equivalent spin systems has been the subject of considerable attention, even after being relevant only for a limited number of substrates. Efficient hyperpolarization in chemically non-equivalent complexes remained a key challenge, hindering the full potential of high-field SABRE and the ability to polarize a broader range of SABRE substrates. This work reports the multinuclear ¹H–¹⁵N pulse sequence for efficient ¹⁵N hyperpolarization in chemically non-equivalent SABRE complexes. This approach relies on the simultaneous ¹H and ¹⁵N radiofrequency excitation of the complex-bound nuclei with weak continuous wave magnetic fields. The proposed pulse sequence enabled the hyperpolarization of the ¹⁵N nuclei in a mixture of the antimicrobial drugs containing a 5-nitroimidazol moiety at their natural ¹⁵N isotopic abundance (0.76% of ¹⁵N polarization). Furthermore, it permitted the precise assignment of the SABRE complexes responsible for the polarization transfer.

Purpose To investigate structural alterations in the thalamus in patients with primary trigeminal neuralgia and provide a detailed perspective on thalamic remodeling in response to chronic pain at the level of individual thalamic nuclei. Methods We analyzed a sample of 62 patients with primary trigeminal neuralgia who underwent surgical treatment, along with 28 healthy participants. Magnetic resonance imaging (MRI) data were acquired using a 3T system equipped with a 16-channel receiver head coil. Segmentation of the thalamic nuclei was performed using FreeSurfer 7.2.0. We divided the group of patients with trigeminal neuralgia into two subgroups: those with right-sided pain and those with left-sided pain. Each subgroup was compared to a control group by means of one-way ANOVA. Associations between morphometric and clinical variables were assessed with Spearman correlation coefficient. Results Our results revealed significant gray matter volume changes in thalamic nuclei among patients with trigeminal neuralgia. Notably, the intralaminar nuclei (centromedian/parafascicular) and nuclei associated with visual and auditory signal processing (lateral and medial geniculate bodies) exhibited significant alterations, contrasting with the ventral group nuclei involved in nociceptive processing. Additionally, we found no substantial volume increase in any of the studied nuclei following successful surgical intervention 6 months later. The volumes of thalamic nuclei were negatively correlated with pain intensity and disease duration. Conclusion The results of this study, although preliminary, hold promise for clinical applications as they reveal previously unknown structural alterations in the thalamus that occur in patients with chronic trigeminal neuralgia.

We discuss applications of the inverse scattering transform, also known as the nonlinear Fourier transform (NFT) in telecommunications, both for nonlinear optical fiber communication channel equalization and time‐domain signal processing techniques. Our main focus is on the challenges and recent progress in the development of efficient numerical algorithms and approaches to NFT implementation.

The paper discusses possible immiscibility between fluoride salt (“cryolite”) and silicate liquids into which the parental melt of the Katugin massif exsolves, and the petrological implications of this phenomenon. Results of a detailed study of the cryolite and zircon are presented. Liquid immiscibility is demonstrated to have triggered the massive crystallization of zircon and, together with the processes of subsequent evolution of the cryolite melt, contributed to the formation of the large cryolite bodies. Data on mineralhosted inclusions were used to estimate the crystallization temperatures of fluoride salt and silicate melts and outline the pathways of their evolution during the formation of the massif. It is shown that the granites of the Katugin and West Katugin massifs were most likely derived from distinct sources, that differed mainly in fluorine content. Data on the chemical composition of three zircon generations identified in the granites of the Katugin massif are presented.

The development of controllable gene editing systems on the base of CRISPR/Cas is an actually problem of modern molecular biology and genetic enginery. Interesting variant of solution of this problem is modification of guide RNA by introduction of photocleavable linkers. We developed the approach to the synthesis of cyclic photocleavable guide crRNA for the CRISPR/Cas9 system with photolinker on the base of 1-(2-nitrophenyl)-1,2-ethanediol (PL). Upon irradiation by UV-light these guide RNA are linearized and CRISPR/Cas9 system is activated. Two chemical methods to the cyclization of RNA were tested: Michael reaction (thiol-maleimide condensation) and Cu-catalyzed azide-alkyne cycloaddition (CuAAC, click-chemistry reaction). For this purpose 5',3'-modified RNA containing reactive groups were prepared. The advantages of CuAAC reaction for cyclic RNA preparation was demonstrated. Effectivity of cyclic RNAs is depends from their secondary structure and ability of reactive groups to draw together. Series of photocleavable and control non-cleavable cyclic crRNA were obtained. It was shown that cyclic crRNAs guide nuclease Cas9 for plasmid cleavage less effective but linearization of photocleavable cyclic crRNA increases extent of plasmid cleavage. Developed approach permits prepare cyclic photocleavable RNA including spatiotemporal activation of guide RNA for gene editing. Photoregulation of gene editing will permit to lower the off-target effects and to carry out the editing more targeting.

Graph neural networks (GNNs) represent a promising instrument for surrogate modeling, capable of handling unstructured computational meshes naturally. We address a typical issue of the accuracy degradation for larger computational domains due to the limited receptive field of GNN models and long-range global interactions between nodes of the mesh. We propose a modification of the GNN architecture allowing to improve the accuracy by a factor of 3 without significant increase in computational costs. The validation tests of the model concentrate on the two-dimensional stationary fluid flow around a bluff body in a channel and corresponding heat transfer. The problem formulation includes bluff bodies of randomly generated shapes and various boundary conditions. The model shows a robust performance for the out-of-domain data, i.e., the flow over an airfoil for different angles of attack.

The paper presents the results of geochemical and Nd whole rock isotopic studies, as well as U–Th–Pb (LA-ICP-MS) geochronological and Hf isotope studies of detrital zircon from metaterrigenous rocks of the Kodar Group of the Udokan Complex, Aldan Shield. It has been established that the rocks of the Kodar Group have an age of 1.99–1.91 Ga, and the rocks of the Chinei and Kemen groups of the Udokan Complex are in the range of 1.90–1.87 Ga. This allows us to raise the question of identifying the Kodar Group as an independent stratigraphic unit. Archean igneous and metamorphic rocks of the Chara-Olekma Geoblock and, probably, the Kalar and Kurulta blocks of the Stanovoy suture zone, as well as Paleoproterozoic (2.04–1.99, 2.08, 2.20 and 2.30 Ga) complexes of active continental margins or ensialic island arcs in the western–northwestern and southern (in modern coordinates) framing of the Chara-Olekma Geoblock, not identified in the region on the modern erosion level, were the sources of terrigenous rocks of the Kodar Group. Erosion of rocks of the igneous arcs and the continental slope led to the accumulation of sediments of the Kodar Group in the retro-arc foreland basin setting, and the subsequent collapse of the orogen and the formation of an intracontinental extension basin led to the accumulation of terrigenous rocks of the Chinei and Kemen groups. Obtained data indicate widespread previously unidentified Paleoproterozoic continental crust formation at about 2.04–1.97 Ga in the western part of the Aldan Shield.

Over the past thirty years, thanks to government initiatives for the “construction” of world-class universities, a cohort of elite (leading) universities has been created in China, covering about 5 % of universities, which have tangible advantages over other universities in student recruitment, teaching, research, funding, and support from local authorities. Despite the similar possibilities gained by universities when they transition to the status of elite institutions, each of them has a different budget structure and distinct operational results, which are primarily associated with the positions of universities in international rankings. Therefore, the aim of the article i s to show whether increased investment in development really allows Chinese universities to be successful in the ranking race. The article describes the sources of funding for Chinese universities, shows the funding structure of some leading institutions, and presents a model of funding for state universities. Special attention is paid to factors affecting the level of funding for Chinese universities, such as belonging to the elite group of universities, geographical location, and the range of educational programs implemented. Based on a sample of 29 leading universities, it is shown that the diversity of funding sources is an indicator of success: as a rule, the best universities have a higher share of income from entrepreneurial activities. At the same time, the volume of the university budget only 50 % determines advancement in rankings. The second reason for success is the “symbolic capital” obtained by universities from participation in the 211 / 985 / “Double First Class” projects, which allows them to achieve significant competitive advantages. Sources of information for analysis included: data from the Ministry of Education of China, web-sites of leading Chinese universities, publications available in the open access network of the Chinese internet, as well as scientific articles published in Russian and leading world publications.

Light-emitting transistors (LETs) represent the next step in the development of light-emitting diodes (LEDs), offering additional control over emission. In this work, the transport properties and spatial distribution of electroluminescence (EL) in the spectral range of 1.2–1.7 μm were studied for lateral p⁺-i-n⁺ LEDs based on silicon-on-insulator structures with self-assembled Ge(Si) islands embedded in photonic crystals. It is shown that due to the low mobility of holes and their effective trapping in the islands, the maximum EL yield is observed at the i/p⁺ junction of the LED. It is demonstrated that the sign and magnitude of the bias voltage applied to the substrate (to the gate) have a significant influence on the transport and emission properties of the LEDs with Ge(Si) islands, turning them into LETs. In particular, applying a negative gate voltage shifts the position of the maximum emission region from the i/p⁺ to the i/n⁺ junction of the LET, which is related to the formation of a hole conductivity channel near the buried oxide layer. The embedding of a specially designed photonic crystal in the i-region of the LET makes it possible to manage the spectral properties of the near-IR emission by changing the sign of the gate voltage. The results obtained may be useful for the future development of optoelectronic devices.