Reports of NAS RA

(In Press) Pauling’s Second Rule and Its Applications: From Inorganic Compounds to Understanding the Function of ATP

Artem R. Oganov — 2026-02-13

Pauling’s five rules for ionic crystals emerged as a generalization of the first experimentally determined crystal structures of inorganic compounds (primarily minerals). It was later discovered that the second rule (the rule of electrostatic valence bond strength balance) is particularly powerful and universal. This essay explains how this rule can be used to explain very easily the differences in the chemistry of entire classes of chemical compounds (e.g., silicates and phosphates), as well as to elucidate the function of ATP as the universal energy currency for all life forms.

New equation for a spin 1/2 particle with three additional characteristics in presence of electromagnetic and gravitational fields

Vasiliy Kisel — 2026-01-15

Within the general Gel’fand–Yaglom method, starting from the extended 28-component representation of the Lorentz group, we construct a new relativistic P-invariant generalized equation for a spin-1/2 particle possessing three characteristics in addition to the electric charge. The model is first developed for a free particle, where the corresponding system of spinor equations is derived and then transformed into spin-tensor form. In this form, we incorporate the interaction with external electromagnetic fields. By eliminating the accessory variables of the complete wave function, we obtain a minimal four-component Dirac-like equation that contains three new interaction terms, interpreted as arising from the additional electromagnetic characteristics of the particle. This approach is further extended to a Riemann space–time background within the conventional tetrad formalism, leading to additional geometrical interaction terms involving the Ricci scalar R(x), the Ricci tensor Rαβ, and the Riemann curvature tensor Rαβρσ(x).

Persistence of Western Diet-Associated Pathway Activity Profiles in Ventricular Tissues

Tamara Sirunyan — 2026-01-30

The consumption of a Western diet (WD), characterized by high levels of fats and sugars, is strongly associated with adverse cardiovascular outcomes. In this case-control study, we evaluated long-term alterations in signaling pathway activities in the left (LV) and right (RV) ventricular tissues of C57Bl/6J mice that were exposed to WD starting at 300 days of age for 125 days before switching to a normal diet (ND). LV and RV tissues were collected at 530 days and subjected to RNA sequencing. Pathway activity for 40 signaling pathways (comprising 709 pathway branches/sinks) was calculated using the topology-aware Pathway Signal Flow (PSF) algorithm, which assesses signal propagation along a pathway based on gene expression levels of its components and their interactions. We observed significant perturbations in 14 pathway branches specifically in LV tissue of male mice, 105 days after the ND switch. These alterations included the downregulation of cardioprotective VEGF signaling and the upregulation of pro-fibrotic TGF-beta signaling, suggesting lasting cardiovascular risks. Furthermore, strong signaling was detected in the cGMP-PKG and FOXO pathways linked to cardiac failure. Finally, pro- and anti-apoptotic signals were simultaneously upregulated, accompanied by the downregulation of cell cycle inhibitors. Notably, no significant gene expression changes were detected in the left ventricular tissue of females, and no significant differences were observed in right ventricular tissue in either sex. These findings suggest that the effects of a Western diet may persist even after transitioning to a healthier diet. Further studies are needed to elucidate the diet-associated risks and develop strategies to mitigate these long-term effects.

(In Press) Study of Various Aspects of the Mechanism of Cα-Alkylation of α-Amino Acids under Phase-Transfer Salen Catalysis Conditions

Anna Tovmasyan — 2026-02-13

The stereodifferentiating ability of salen complexes of Cu(II), Ni(II), and Zn(II) ions in Cα-alkylation reactions of amino acids as phase-transfer catalysts (PTC) has been investigated. It was found that substituents in the 3-position of the aromatic ring of the salicylidene moiety of the complexes have a particularly strong effect on catalytic activity. The highest efficiency was observed for the 3-methoxy-substituted salen complex of the Zn(II) — ee > 90%. DFT calculations showed that the stereodifferentiating ability of the catalyst depends on the ratio of propeller-like and cross-like conformational structures of dimeric binuclear salen complex molecules in the alkylation transition state. It was demonstrated that propeller-like conformational isomers, which predominate in the dimeric binuclear structure of 3-allyl-substituted salen complexes, correspond to the catalytically inactive form and inhibit asymmetric catalysis. In contrast, cross-like isomers, which dominate in the dimeric binuclear structure of 3-methoxy-substituted salen complexes, ensure high stereodifferentiating activity and promote asymmetric catalysis. The DFT calculation data correlate clearly with the experimental results.

(In Press) On Conditionally Universal Functions with respect to the Walsh system

Martin Grigoryan — 2026-02-13

This paper proves theorems on the existence of conditionally universal functions and universal triads with respect to the Walsh system defined by the author, whose the method of proving allows obtaining the novel approach for constructing the universal series by in Walsh system: transform any measurable almost everywhere finite function, by varying its values on a certain set of arbitrarily small measure, to a function such that, after choosing the corresponding signs for the Fourier series terms in the Walsh system of the corrected function, we can achieve the point when the obtained series is a universal series in class all measurable functions.

Aggrandization of spaces: a new general approach and application

Alexey Karapetyants — 2026-02-13

Our study is based on recent results concerning the so-called local aggrandization of Lebesgue spaces. We extend this framework to the case of arbitrary Banach spaces of functions on metric spaces. Furthermore, we demonstrate that grand spaces of holomorphic functions can be equivalently defined through aggrandization associated exclusively with the boundary. This paper review presents recent results obtained in collaboration with Stefan Samko and provides a concise introduction to the classical theory of grand spaces for comparative analysis. We also discuss the underlying motivation for investigating these spaces.

Modern Synthetic Approaches to Cubebene and Related Sesquiterpene Frameworks

William Croydon — 2026-02-19

Cubebenes and related sesquiterpenes, featuring a tricyclo[4.4.0.0¹,⁵]decane framework, exhibit notable structural complexity and diverse bioactivity. This review highlights key synthetic approaches toward these molecules, including diazo-mediated cyclopropanation, metal-catalysed enyne cyclisation, bicycloannulation cascades, and photochemical rearrangements. Mechanistic and stereochemical aspects are discussed, highlighting progress in diastereo- and enantioselective methodologies. Although substantial advances have been achieved, efficient access to higher cubebene analogues remains a synthetic challenge. Integration of bioinspired design, modern synthetic methods, and asymmetric catalysis is expected to further advance concise and stereoselective synthesis of these complex architectures.