Publications by authors named "Krylov A"

A novel molecular structure that bridges the fields of molecular optical cycling and molecular photoswitching is presented. It is based on a photoswitching molecule azobenzene functionalized with one and two CaO- groups, which can act as optical cycling centers (OCCs). This paper characterizes the electronic structure of the resulting model systems, focusing on three questions: (1) how the electronic states of the photoswitch are impacted by a functionalization with an OCC; (2) how the states of the OCC are impacted by the scaffold of the photoswitch; and (3) whether the OCC can serve as a spectroscopic probe of isomerization.

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Two-dimensional materials with new physical phenomena are gaining popularity due to their unique properties. In recent years, a new family of layered compounds inspired by the minerals valleriite and tochilinite which are composed of alternating quasi-atomic sheets of transition metal chalcogenides (sulfides and selenides of Fe, Fe-Cu and other metals) and hydroxides of Mg, Al, Fe, Li, ., assembled electrostatic interaction, has arisen as a new synthetic platform for 2D materials.

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One of the most important areas of application for equation-of-motion coupled-cluster (EOM-CC) theory is the prediction, simulation, and analysis of various types of electronic spectra. In this work, the EOM-CC method for ionized states, known as EOM-IP-CC, is applied to the closely lying and coupled pair of states of the ozone cation─ and ─using highly accurate treatments including up to the full single, double, triple, and quadruple excitations (EOM-IP-CCSDTQ). Combined with a venerable and powerful method for calculating vibronic spectra from the Hamiltonian produced by EOM-IP-CC calculations, the simulations yield a spectrum that is in good agreement with the photoelectron spectrum of ozone.

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We demonstrate generation of both 17 fs ultrashort pulses and 862 nm spanning supercontinuum (SC) directly from an erbium-doped fiber (EDF) oscillator, utilizing extra-cavity management of nonlinearity and second-order dispersion using a combination of commercially available SMF-28 and specially developed homemade fiber with anomalous dispersion and enhanced nonlinearity. The simple but accurately designed fiber ring laser, passively mode-locked by nonlinear polarization evolution, offers a self-starting pulse generation with a dechirped duration of 51.8 fs as well as a 19.

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Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is strongly associated with obesity. Sex and age affect MASLD prevalence and pathophysiology. The use of animal models fed Western-style diets is vital for investigating the molecular mechanisms contributing to metabolic dysregulation and for facilitating novel drug target identification.

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This commentary documents how federal funding agencies are changing the criteria by which they distribute taxpayer money intended for scientific research. Increasingly, STEMM (Science, Technology, Engineering, Mathematics, and Medicine) funding agencies are requiring applicants for funding to include a plan to advance DEI ("Diversity, Equity, and Inclusion") in their proposals and to dedicate a part of the research budget to its implementation. These mandates undermine the academic freedom of researchers and the unbiased generation of knowledge needed for a well-functioning democracy.

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The study of Na-carbonates stability and their transformations in aqueous carbonate fluid under high P-T conditions is relevant from the point of view of the understanding geochemical processes of the Na-assisted carbon circulation in the Earth's crust and subduction zones. In situ Raman study of Na-bearing carbonate-water-Fe-metal system in diamond anvil cell (DAC) at high P-T conditions revealed that carbonates decompose with abiogenic formation of formates and other organic compounds that differs from behavior of carbonates in dry system. XRD and FTIR methods have been used additionally to determine the phase composition.

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The purpose of this study was to study the correlation of the body weight of Yakuts with the variability of polymorphisms rs174537, rs174546 and rs3834458 of the region to identify the connection of certain genotypes with obesity. For genotyping, classical methods of PCR-RFLP analysis were used. A sample of 446 DNA samples from Yakut volunteers without chronic diseases (143 women and 303 men) was studied.

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Molecules cooled to ultracold temperatures are desirable for applications in fundamental physics and quantum information science. However, cooling polyatomic molecules with more than six atoms has not yet been achieved. Building on the idea of an optical cycling center (OCC), a moiety supporting a set of localized and isolated electronic states within a polyatomic molecule, molecules with two OCCs (bi-OCCs) may afford better cooling efficiency by doubling the photon scattering rate.

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We report high-level calculations of the excited states of [2,2]-paracyclophane (PCP), which was recently investigated experimentally by ultrafast pump-probe experiments on oriented single crystals [Haggag et al., ChemPhotoChem 6 e202200181 (2022)]. PCP, in which the orientation of the two benzene rings and their range of motion are constrained, serves as a model for studying benzene excimer formation.

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This study assesses the performance of various meta-generalized gradient approximation (meta-GGA), global hybrid, and range-separated hybrid (RSH) density functionals in capturing the excited-state properties of organic chromophores and their excited-state complexes (exciplexes). Motivated by their uses in solar energy harvesting and photoredox CO reduction, we use oligo-(p-phenylenes) and their excited-state complexes with triethylamine as model systems. We focus on the fluorescence properties of these systems, specifically emission energies.

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A variety of lakes located in the dry steppe area of southwestern Siberia are exposed to rapid climatic changes, including intra-century cycles with alternating dry and wet phases driven by solar activity. As a result, the salt lakes of that region experience significant fluctuations in water level and salinity, which have an essential impact on the indigenous microbial communities. But there are few microbiological studies that have analyzed this impact, despite its importance for understanding the functioning of regional water ecosystems.

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Background: The Mekong River is the 10 largest river in the world. It is recognised as the most productive river in Southeast Asia and economically essential to the region, with an estimated 60-65 million people living in the lower Mekong Basin. The Mekong Delta within Vietnam is considered a highly vulnerable ecosystem under threat from increasing anthropogenic pressure, such as dam construction and, as a consequence, the Delta is sinking and altering the natural hydrological cycle.

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The threshold structural transformation of the DUT-4 metal-organic framework (MOF) from an ordered to distorted phase during exposure to ambient conditions has been revealed. The X-ray diffraction analysis, Raman and FTIR spectroscopy, scanning electron microscopy and synchronous thermal analysis have been used for investigation. The reversible effect of exposure time and humidity on such a phase transition has been confirmed.

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A comparative analysis of the psychological characteristics of the working and non-working population in the context of personal employment, demand and quality life. The study was conducted with the participation of 51 women and 58 men, age 65,35±5,25 years. Randomization into two groups: the 1st group - 59 people of those continuing to work in the field of higher and vocational education; the 2nd group (50 people) consisted of non-working pensioners whose labor activity was related to teaching, taking care of their families, children and grandchildren, the circle of their social contacts is limited by the connections necessary to ensure life.

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We present state-of-the-art calculations of the core-ionization spectrum of water. Despite significant progress in procedures developed to mitigate various experimental complications and uncertainties, the experimental determination of ionization energies of solvated species involves several non-trivial steps such as assessing the effect of the surface potential, electrolytes, and finite escape depths of photoelectrons. This provides a motivation to obtain robust theoretical values of the intrinsic bulk ionization energy and the corresponding solvent-induced shift.

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Aim: To study the contribution of the Ala54Thr genetic polymorphism of the gene to the risk of developing type 2 diabetes mellitus among the Yakut population.

Materials And Methods: The study included participants who filled out a questionnaire approved by the Local Committee on Biomedical Ethics at the Yakut Science Centre of complex medical problems and voluntarily signed an informed consent to conduct a genetic study. The sample consisted of 181 patients of the endocrinological department of the Republican Hospital No.

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We present the two-photon absorption (2PA) spectrum of aqueous thiocyanate calculated using high-level quantum-chemistry methods. The 2PA spectrum is compared to the one-photon absorption (1PA) spectrum computed using the same computational protocol. Although the two spectra probe the same set of electronic states, the intensity patterns are different, leading to an apparent red-shift of the 2PA spectrum relative to the 1PA spectrum.

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Science is among humanity's greatest achievements, yet scientific censorship is rarely studied empirically. We explore the social, psychological, and institutional causes and consequences of scientific censorship (defined as actions aimed at obstructing particular scientific ideas from reaching an audience for reasons other than low scientific quality). Popular narratives suggest that scientific censorship is driven by authoritarian officials with dark motives, such as dogmatism and intolerance.

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Damage to light-sensing photoreceptors (PRs) occurs in highly prevalent retinal diseases. As humans cannot regenerate new PRs, these diseases often lead to irreversible blindness. Intriguingly, animals, such as the zebrafish, can regenerate PRs efficiently and restore functional vision.

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Cells of two molecular genetic types of breast cancer-hormone-dependent breast cancer (ZR-75 cell line) and triple-negative breast cancer (BT-20 cell line)-were studied using atomic force microscopy and an optical nanomotion detection method. Using the Peak Force QNM and Force Volume AFM modes, we revealed the unique patterns of the dependence of Young's modulus on the indentation depth for two cancer cell lines that correlate with the features of the spatial organization of the actin cytoskeleton. Within a 200-300 nm layer just under the cell membrane, BT-20 cells are stiffer than ZR-75 cells, whereas in deeper cell regions, Young's modulus of ZR-75 cells exceeds that of BT-20 cells.

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Among various techniques designed for studying open-shell species, electron paramagnetic resonance (EPR) spectroscopy plays an important role. The key quantity measured by EPR is the -tensor, describing the coupling between an external magnetic field and molecular electronic spin. One theoretical framework for quantum chemistry calculations of -tensors is based on response theory, which involves substantial developments that are specific to the underlying electronic structure models.

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States with core- or inner-shell vacancies, which are commonly created by absorption of high-energy photons, can decay by a two-electron process in which one electron fills the core hole and the second one is ejected. These processes accompany many X-ray spectroscopies. Depending on the nature of the initial core- or inner-shell-hole state and the decay valence-hole state, these processes are called Auger decay, intermolecular Coulomb decay, or electron-transfer-mediated decay.

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