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The article deals with analysis of the material from the Bystrovka necropolis (Bystrovka-1,2,3) of the Early Iron Age in the Upper Ob region. All these precedents were integrated into the context of various types of burial rites: inhumation, secondary burials, and ritual partial burials. On the surface of individual heads there are various traces of violent and industrial influences – stabbing, punching and cutting tools. In accordance with the shape of the holes from the piercing tools on the surface of some of the skulls from Bystrovka-2, kurgan-9, it can be determined that they were made with a chekhan with a subrectangular section. This type of impact weapon of the Early Iron Age is not widely represented in the north of the Upper Ob region. At the same time, most of the iron chasings of the Early Iron Age of the Upper Ob had a predominantly rounded cross-section of their striker. It should also be noted that the holes from the blows of the chekhan on the skull in Altai had a predominantly rounded section. Whereas, on the territory of the Middle Yenisei (Tagar culture), the holes from the chekhan of the coinage also had a predominantly sub-square section. Such a similarity of the entrance holes from the coinage on the Middle Yenisei and the Upper Ob (Bystrovka-2) indirectly indicates that the coinage with which the blows were struck could be of “Tagar” origin. Along with these features, it should be noted that, judging by the tracing features of striking with a coin on one of the skulls from Bystrovka-2 kurgan-9, it was struck on the head when the person was kneeling in front of the attacker. It is this pose that is shown on one of the petroglyphs on Mount Kunya in the Middle Yenisei. The presence of an extensive report of radiocarbon and dendrochronological dating for the Bystrovka necropolis makes it possible, along with various objects of the object complex (arrowheads, ceramic vessels, etc.), to date manipulations with the heads of those buried in the middle – the last third of the 1st millennium BC. In general, all these facts fit into the format of the “archeology of violence” and illustrate not only various variants of injuries from violent actions, but also complex and multi-stage rituals reflected in the funeral rites.

We show that driving optical phonons above a threshold fluence induces spatiotemporal orders, where material properties oscillate at an incommensurate wave vector q_{0} in space and at half the drive frequency in time. The order is robust against temperature on timescales much larger than the lifetime of the excited modes and can be accompanied by a static 2q_{0} modulation. We make predictions for time-resolved diffraction and provide estimates for candidate materials. Our results show the possibility of using THz waves in solids to realize tunable incommensurate orders on the nanoscale.

The robustness of the macroscopic quantum nature of a superconductor can be characterized by the superfluid stiffness, ρ s , a quantity that describes the energy required to vary the phase of the macroscopic quantum wavefunction. In unconventional superconductors, such as cuprates, the low-temperature behaviour of ρ s markedly differs from that of conventional superconductors owing to quasiparticle excitations from gapless points (nodes) in momentum space. Intensive research on the recently discovered magic-angle twisted graphene family has revealed, in addition to superconducting states, strongly correlated electronic states associated with spontaneously broken symmetries, inviting the study of ρ s to uncover the potentially unconventional nature of its superconductivity. Here we report the measurement of ρ s in magic-angle twisted trilayer graphene (TTG), revealing unconventional nodal-gap superconductivity. Utilizing radio-frequency reflectometry techniques to measure the kinetic inductive response of superconducting TTG coupled to a microwave resonator, we find a linear temperature dependence of ρ s at low temperatures and nonlinear Meissner effects in the current-bias dependence, both indicating nodal structures in the superconducting order parameter. Furthermore, the doping dependence shows a linear correlation between the zero-temperature ρ s and the superconducting transition temperature T c , reminiscent of Uemura's relation in cuprates, suggesting phase-coherence-limited superconductivity. Our results provide strong evidence for nodal superconductivity in TTG and put strong constraints on the mechanisms of these graphene-based superconductors., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer Nature Limited.)

Pyridines undergo a facile S N H Ar phosphinylation with H -phosphinates under catalyst- and solvent-free conditions (50-55 °C) in the presence of benzoylphenylacetylene to afford 4-phosphinylpyridines in up to 68% yield. In this reaction, benzoylphenylacetylene activates the pyridine ring by the formation of a 1,3(4)-dipolar complex, deprotonates H -phosphinates to generate P-centered anions and finally acts as an oxidizer, being eliminated from an intermediate ion pair. Terminal electron-deficient acetylenes (methyl propiolate and benzoylacetylene) are inefficient as mediators in the above S N H Ar process.

When the electron-phonon coupling is quadratic in the phonon coordinates, electrons can pair to form bipolarons due to phonon zero-point fluctuations, a purely quantum effect. We study superconductivity originating from this pairing mechanism in a minimal model and reveal that, in the strong coupling regime, the critical temperature (T_{c}) is only mildly suppressed by the coupling strength, in stark contrast to the exponential suppression in linearly coupled systems, thus implying higher optimal T_{c} values. We demonstrate that large coupling constants of this flavor are achieved in known materials such as perovskites, and discuss strategies to realize such superconductivity using superlattices.

Twisted interfaces between stacked van der Waals (vdW) cuprate crystals present a platform for engineering superconducting order parameters by adjusting stacking angles. Using a cryogenic assembly technique, we construct twisted vdW Josephson junctions (JJs) at atomically sharp interfaces between Bi 2 Sr 2 CaCu 2 O 8+ x crystals, with quality approaching the limit set by intrinsic JJs. Near 45° twist angle, we observe fractional Shapiro steps and Fraunhofer patterns, consistent with the existence of two degenerate Josephson ground states related by time-reversal symmetry (TRS). By programming the JJ current bias sequence, we controllably break TRS to place the JJ into either of the two ground states, realizing reversible Josephson diodes without external magnetic fields. Our results open a path to engineering topological devices at higher temperatures.

An efficient one-pot synthesis of 1,2,5-trisubstituted-1,2-dihydro-3 H -pyrrole-3-thiones (up to 91% yield), representatives of essentially new heterocyclic systems, by the successive treatment of available propargylamines with acyl chlorides (PdCl 2 /CuI/Ph 3 P/Et 3 N, toluene, 40-45 °C, 3 h) and sodium sulfide (Na 2 S·9H 2 O, EtOH, 20-25 °C, 7 h) has been developed. The synthesis comprises the addition of sulfide anions to the formed aminoacetylenic ketones followed by dehydrative cyclization of the prototropically rearranged adducts.

We report the experimental observation of dielectric relaxation by quantum critical magnons. Complex capacitance measurements reveal a dissipative feature with a temperature-dependent amplitude due to low-energy lattice excitations and an activation behavior of the relaxation time. The activation energy softens close to a field-tuned magnetic quantum critical point at H=H_{c} and follows single-magnon energy for H>H_{c}, showing its magnetic origin. Our study demonstrates the electrical activity of coupled low-energy spin and lattice excitations, an example of quantum multiferroic behavior.

We show that interlayer current induces topological superconductivity in twisted bilayers of nodal superconductors. A bulk gap opens and achieves its maximum near a "magic" twist angle θ_{MA}. Chiral edge modes lead to a quantized thermal Hall effect at low temperatures. Furthermore, we show that an in-plane magnetic field creates a periodic lattice of topological domains with edge modes forming low-energy bands. We predict their signatures in scanning tunneling microscopy. Estimates for candidate materials indicate that twist angles θ∼θ_{MA} are optimal for observing the predicted effects.

Superconductivity in low carrier density metals challenges the conventional electron-phonon theory due to the absence of retardation required to overcome Coulomb repulsion. Here we demonstrate that pairing mediated by energy fluctuations, ubiquitously present close to continuous phase transitions, occurs in dilute quantum critical polar metals and results in a dome-like dependence of the superconducting T c on carrier density, characteristic of non-BCS superconductors. In quantum critical polar metals, the Coulomb repulsion is heavily screened, while the critical transverse optical phonons decouple from the electron charge. In the resulting vacuum, long-range attractive interactions emerge from the energy fluctuations of the critical phonons, resembling the gravitational interactions of a chargeless dark matter universe. Our estimates show that this mechanism may explain the critical temperatures observed in doped SrTiO 3 . We provide predictions for the enhancement of superconductivity near polar quantum criticality in two- and three-dimensional materials that can be used to test our theory., (© 2022. The Author(s).)

Publications covering a new easy metal-free functionalization of pyridinoids (pyridines, quinolines, isoquinolines, acridine) under the action of the system of electron-deficient acetylenes (acetylenecarboxylic acid esters, acylacetylenes)/ P -nucleophiles (phosphine chalcogenides, H -phosphonates) are reviewed. Special attention is focused on a S N H reaction of the regioselective cross-coupling of pyridines with secondary phosphine chalcogenides triggered by acylacetylenes to give 4-chalcogenophosphorylpyridines. In these processes, acetylenes act as three-modal adjuvants (i) activating the pyridine ring towards P -nucleophiles, (ii) deprotonating the P-H bond and (iii) facilitating the nucleophilic addition of the P -centered anion to a heterocyclic moiety followed by the release of the selectively reduced acetylenes ( E -alkenes).

Secondary phosphine chalcogenides react with primary amino alcohols under mild conditions (room temperature, molar ratio of the initial reagents 1 : 1) in a CCl4/Et3N oxidizing system to chemoselectively deliver amides of chalcogenophosphinic acids with free OH groups. Under similar conditions, mono-cross-coupling between secondary phosphine chalcogenides and 1,2- or 1,3-aminophenols proceeds only with the participation of phenolic hydroxyl to give aminophenylchalcogenophosphinic O-esters. The yields of the synthesized functional amides or esters are 60-85%.

Effect of amines on formation of gold nanoparticles (AuNPs)/polymer nanocomposites has been observed and studied. Nanocomposites based on polyurethane foam and AuNPs were synthesized by interaction between the polymer modified with sodium borohydride and aqueous solution of tetrachloroauric acid. It has been shown that some amines cause a remarkable decrease of the surface plasmon resonance band of AuNPs in the nanocomposite material. Both aliphatic and aromatic amines as well as amines containing several amino groups were studied. A possible mechanism of the effect is discussed. It is probably based on stabilization of AuNPs with an amine that entails a decrease in the degree of their adsorption on PUF and appearance of the stabilized AuNPs in solution. The decrease of the nanocomposite surface plasmon resonance band is proportional to the concentration of amine in the solution. Based on this effect, a method for the determination of cetylamine, β-naphthylamine and neomycin in water and medical formulations using a monitor calibrator as a portable household tool is proposed. Under the selected conditions, the detection limits for amines were in the range of 0.7-1.5 μM, the determination ranges were approximately an order of magnitude. The observed color change of the nanocomposite samples also provides a good basis for semiquantitative determinations., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Motivated by recent experiments on magnetically frustrated heavy fermion metals, we theoretically study the phase diagram of the Kondo lattice model with a nonmagnetic valence bond solid ground state on a ladder. A similar physical setting may be naturally occurring in [Formula: see text], [Formula: see text], and [Formula: see text] compounds. In the insulating limit, the application of a magnetic field drives a quantum phase transition to an easy-plane antiferromagnet, which is described by a Bose-Einstein condensation of magnons. Using a combination of field theoretical techniques and density matrix renormalization group calculations we demonstrate that in one dimension this transition is stable in the presence of a metallic Fermi sea, and its universality class in the local magnetic response is unaffected by the itinerant gapless fermions. Moreover, we find that fluctuations about the valence bond solid ground state can mediate an attractive interaction that drives unconventional superconducting correlations. We discuss the extensions of our findings to higher dimensions and argue that depending on the filling of conduction electrons, the magnon Bose-Einstein condensation transition can remain stable in a metal also in dimensions two and three., Competing Interests: The authors declare no competing interest.

Motivated by recent experimental realizations of polar metals with broken inversion symmetry, we explore the emergence of strong correlations driven by criticality when the polar transition temperature is tuned to zero. Overcoming previously discussed challenges, we demonstrate a robust mechanism for coupling between the critical mode and electrons in multiband metals. We identify and characterize several novel interacting phases, including non-Fermi liquids, when band crossings are close to the Fermi level and present their experimental signatures for three generic types of band crossings.

Quinolines undergo catalyst-free double CH-functionalization upon treatment with secondary phosphine oxides (70-75 °C, 20-48 h) followed by oxidation of the intermediate 2,4-bisphosphoryltetrahydroquinolines with chloranil. The yields of the target 2,4-bisphosphorylated quinolines are up to 77%. Thus, a double-S N H Ar reaction sequence in the same molecule of quinoline has been realized. In the case of 2,4-bisphenylphosphoryltetrahydroquinolines, the aromatization occurs with elimination of one molecule of diphenylphosphine oxide to afford the products of monofunctionalization, 4-diphenylphosphorylquinolines, in 40-45% yields.

Quinolines react with acylacetylenes and secondary phosphine chalcogenides at 20-75 °C to afford N-acylvinyl-2(1)-chalcogenophosphoryldihydroquinolines in good and excellent yields. Unlike the pyridine-derived similar intermediates, which eliminate E-alkenes to give aromatic chalcogenophosphorylpyridines, thereby completing S N H Ar reaction, with quinolines, the reaction stops at the formation of the above phosphorylated N-acylvinyl-dihydroquinolines, thus representing a pendant S N H Ar process. This reaction opens a one-pot atom-economic single-step access to pharmaceutically targeted phosphorylated functionalized dihydroquinolines and isoquinolines.

A method is described for sensitive and selective detection of iodine by using a paper strip modified with silver triangular nanoplates (AgTNPs). It is based on the extraction of iodine from a solution into a flow of air via dynamic gas extraction and transferring it through a reactive paper modified with AgTNPs. The interaction of AgTNPs with iodine results in a color change from blue to white. This can be visually detected and monitored by digital colorimetry. The dynamic gas extraction is highly selective for volatile compounds so that a sample pretreatment is minimal. Due to the sensitivity of AgTNPs for iodine, the limit of its detection is as low as 7 μg L -1 , and the analytical range is of 20-200 μg L -1 . The method also was applied in a new approach for determination of organic compounds that can interact with iodine. The organic compound is exposed to an excess of iodine, and this is followed by detection of residual iodine as described above. The method was applied to the determination of ascorbic acid, caffeine and the drug metamizole. Graphical abstract Schematic representation of a procedure of organic iodine-interacting compounds (Org.) determination. It is based on their iodination followed by gas extraction of the residual iodine, its interaction with silver triangular nanoplates and colorimetric detection with a scanner.

Acridine adds secondary phosphine chalcogenides HP(X)R 2 (X = O, S, Se; R = Ar, ArAlk) under catalyst-free conditions at 70-75 °C (both in the presence and absence of the electron-deficient acetylenes) to give 9-chalcogenophosphoryl-9,10-dihydroacridines in 61-94% yields. This contrasts with pyridines, which under similar conditions undergo an S N H Ar reaction, wherein electron-deficient acetylenes play the role of oxidants. For acridine, the S N H Ar step has been accomplished by the oxidation of the intermediate 9-phosphoryl-9,10-dihydroacridines (X = O) with chloranil.

Positively charged polyhexamethylene guanidine hydrochloride-stabilized silver nanoparticles (PHMG-AgNPs) were prepared and applied as a colorimetric probe for single-step determination of pyrophosphate and sulfate. The approach is based on the nanoparticles aggregation leading to change in their absorption spectra and color of the solution. Due to both electrostatic and steric stabilization these nanoparticles show decreased sensitivity relatively to many common anions, which allows for simple and rapid direct single-step determination of pyrophosphate and sulfate. Effects of different factors (time of interaction, pH, concentrations of anions and the nanoparticles) on aggregation of PHMG-AgNPs and analytical performance of the procedure were investigated. The method allows for the determination of pyrophosphate and sulfate in the range of 0.16-2μgmL -1 and 20-80μgmL -1 with RSD of 2-5%, respectively. The analysis can be performed using either spectrophotometry or naked-eye detection. Practical application of the method was shown by the example of pyrophosphate determination in baking powder sample., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Pyridines undergo site selective cross-coupling with secondary phosphine chalcogenides (oxides, sulfides, and selenides) in the presence of acylphenylacetylenes under metal-free mild conditions (70-75 °C, MeCN) to afford 4-chalcogenophosphoryl pyridines in up to 71% yield. In this new type of SNHAr reaction acylacetylenes act as oxidants, being stereoselectively reduced to the corresponding olefins of the E-configuration.

The article describes a novel approach towards improving selectivity of volatile compounds detection using metal nanoparticles. It is based on combination of sensitive optical detection using convenient nanoparticle-modified paper test strips and dynamic gas extraction improving selectivity to volatile compounds. A simple and inexpensive setup allowing for realization of this combination is described. Analytical prospects of the approach are shown by the example of chlorine determination in highly salted aqueous solutions using silver triangular nanoplates and digital colorimetry. The limit of detection is equal to 0.03mgL -1 and the determination range is 0.1-2mgL -1 . This determination can be successfully carried out in solutions containing at least 2·10 5 greater molar amounts of Na + , K + , Zn 2+ , Cl - , SO 4 2- , and H 2 PO 4 - with no sample pretreatment. The approach seems to be compatible with different types of nanoparticles with respect to detection of various analytes, thus having good opportunities for further development., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this paper, we report on a novel type of nanocomposites based on gold nanoparticles (AuNPs) and polyurethane foam (PUF), which represents an ability of AuNP aggregation on solid polymer matrix with the strongly different selectivity in comparison with aggregation of the same AuNPs in solution. This may indicate that a new type of aggregation takes place, which can be called solid-phase aggregation. A systematic study using diffuse reflectance spectroscopy revealed features of the solid-phase aggregation. The PUF-AuNPs nanocomposites can be synthesized by a simple and low cost procedure based on adsorption of different type AuNPs from aqueous solution onto PUF. Prospects of obtained composite materials for sensing some organic compounds using diffuse reflectance spectroscopy or colorimetry are shown. This nanocomposites have the increased selectivity to thiols allowing for their determination with limits of detection of 0.01-0.05μgmL -1 and relative standard deviations of 3-5%. Charged species that affect AuNPs in solution do not influence them on PUF., (Copyright © 2016 Elsevier B.V. All rights reserved.)

We described our experience in using the new noninvasive hemodynamic monitoring (esCCO), which allowed recording most important parameters of heart capacity. Infusion therapy during laparoscopic operations might be based on dynamic of systolic blood volume. This functional approach can be used for evaluation of heart reaction on bolus fluid load, to optimike volemic status in situations associated with dynamical blood circulation changes. We compared intraoperative infused fluid volumes, calculated by traditional approach and by target approach. The obtained results had significant differences among groups, and didn't correspond with "liberal" and "restrictive" strategy for infusion therapy.

So far, the ongoing debate about the appropriateness of combining drugs with different mechanisms of analgesic action for optimal antinociceptive protection. The review deals with the theoretical calculations arguing with the physiological rationality for the inclusion of central α2-agonists in the scheme of modern multimodal analgesia. We have presented data from recent reviews regarding the efficacy and safety of intraoperative application of dexmedetomidine as a one of the latest drugs in this class.

Unlabelled: The article deals with a study of efficacy and safety of the dexmedetomidine as an analgesic adjuvant drug for anaesthesia during laparoscopic gynecological and abdominal surgeries. Patients and methods: 32 patients received intraoperative infusion of dexmedetomidine. We assessed an effects of dexmedetomidine on data of central circulation during surgeries., Conclusions: The use of dexmedetomidine allows to decrease an amount of opioid analgesics, inhalation anaesthetics and to avoid severe changes of circulation during traumatic phases of surgeries.

The study deals with two mostly discussed techniques of postoperative analgesia for total knee joint arthroplasty. Surgeries were performed under subarachnoid anaesthesia with intravenous sedation. 9 patients of first group in received prolonged femoral nerve blockade as a component of multimodal analgesia. 8 patients of second group received epidural infusion of naropine. If basic technique of analgesia was not effective patients received trimeperidine 20 mg intramuscular. Patients of second group had less pain syndrome (in order to visual analogue scale) and did not need additional administration of opioids.

Mutations in pancreatic duodenal homeobox 1 (PDX-1) can cause a monogenic form of diabetes (maturity onset diabetes of the young 4) in humans, and silencing Pdx-1 in pancreatic β-cells of mice causes diabetes. However, it is not established whether epigenetic alterations of PDX-1 influence type 2 diabetes (T2D) in humans. Here we analyzed mRNA expression and DNA methylation of PDX-1 in human pancreatic islets from 55 nondiabetic donors and nine patients with T2D. We further studied epigenetic regulation of PDX-1 in clonal β-cells. PDX-1 expression was decreased in pancreatic islets from patients with T2D compared with nondiabetic donors (P = 0.0002) and correlated positively with insulin expression (rho = 0.59, P = 0.000001) and glucose-stimulated insulin secretion (rho = 0.41, P = 0.005) in the human islets. Ten CpG sites in the distal PDX-1 promoter and enhancer regions exhibited significantly increased DNA methylation in islets from patients with T2D compared with nondiabetic donors. DNA methylation of PDX-1 correlated negatively with its gene expression in the human islets (rho = -0.64, P = 0.0000029). Moreover, methylation of the human PDX-1 promoter and enhancer regions suppressed reporter gene expression in clonal β-cells (P = 0.04). Our data further indicate that hyperglycemia decreases gene expression and increases DNA methylation of PDX-1 because glycosylated hemoglobin (HbA1c) correlates negatively with mRNA expression (rho = -0.50, P = 0.0004) and positively with DNA methylation (rho = 0.54, P = 0.00024) of PDX-1 in the human islets. Furthermore, while Pdx-1 expression decreased, Pdx-1 methylation and Dnmt1 expression increased in clonal β-cells exposed to high glucose. Overall, epigenetic modifications of PDX-1 may play a role in the development of T2D, given that pancreatic islets from patients with T2D and β-cells exposed to hyperglycemia exhibited increased DNA methylation and decreased expression of PDX-1. The expression levels of PDX-1 were further associated with insulin secretion in the human islets.

The aim of the study is to analyze sepsis and septic shock incidence and their influence on the outcome in critically ill patients with intracranial hemorrhage. Sepsis incidence (33,7%) and septic shock incidence (18,6%) in the patients studied did not depend on intracranial hemorrhage etiology. Septic complications led to higher mortality which was 22,8% in patients with sepsis and 74,4% in patients with septic shock. Sepsis and septic shock risk factors are defined. The problem of sepsis and septic shock diagnosis in critically ill patients with intracranial hemorrhage are highlighted.

We show both theoretically and experimentally that biphoton wave packets generated via spontaneous parametric down-conversion can be strongly anisotropic and highly entangled. The conditions under which these effects exist are found and discussed.