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Structural changes in phosphatidylcholine lipid membranes caused by the introduction of insoluble CoFe 2 O 4 nanoparticles (NPs) are analyzed. Changes in nuclear magnetic resonance spectrum, infrared spectrum, and ionic conductivity of membranes are observed with the addition of NPs. The presence of NPs in membranes is proved by atomic force and magnetic force microscopy. Structural changes in the membranes in the vicinity of the lipid C-O bonds caused by NPs are observed by Scanning near-field optical microscopy. Analysis of nuclear magnetic resonance (NMR) spectra allowed us to identify the affected atomic groups in the membrane surface layers. Conductivity measurements of the bilayer membranes were performed in DC as well as in time-resolved modes. Hydrophobic NPs stimulate surface distortion and creation of pores, which depending on NP concentration leads to an increase in the ionic conductivity of membranes. Concentration dependence demonstrating percolation threshold was analyzed in the frame of the fractal theory approach.

The functional diversities of two-dimensional (2D) material devices with simple architectures are ultimately limited by immature doping techniques. An alternative strategy is to use geometry-asymmetric metal-semiconductor-metal (GA-MSM) structures, which enable the basic functions of semiconductor junctions such as rectification and photovoltaics. Here, the mixed-dimensional van der Waals heterostructures (MDvdWHs) based on the separation and self-assembly of p-type SnS layered nanosheets (NSs) and n-type SnS 2 nanoparticles (NPs) are obtained using an aqueous phase exfoliation (APE) method. Due to the surface charge transfer doping, the carrier transport mechanism of devices based on MDvdWHs turns from thermionic field emission (TFE) to thermionic emission (TE), with the rectification factor ( I forward ) changing from 0.7 to 3. To further illustrate the experimental results, the generic current transport models of GA-MSM devices have been established based on the TE and TFE mechanisms in which the TE and TFE mechanisms lead to opposite rectification phenomena in good agreement with the experimental results. The GA-MSM devices show a photovoltaic effect with a high responsivity of 35 A W I and detectivity of 3.4 × 10 reverse ) changing from 0.7 to 3. To further illustrate the experimental results, the generic current transport models of GA-MSM devices have been established based on the TE and TFE mechanisms in which the TE and TFE mechanisms lead to opposite rectification phenomena in good agreement with the experimental results. The GA-MSM devices show a photovoltaic effect with a high responsivity of 35 A W -1 and detectivity of 3.4 × 10 11 . This study not only provides a novel strategy to design photovoltaic devices with MDvdWHs, but more importantly, we have established fundamental models for the rectification behavior of GA-MSM devices.1/2 W -1 . This study not only provides a novel strategy to design photovoltaic devices with MDvdWHs, but more importantly, we have established fundamental models for the rectification behavior of GA-MSM devices.

A series of novel water-soluble salts of benzofuroxans was achieved via aromatic nucleophilic substitution reaction of 4,6-dichloro-5-nitrobenzofuroxan with various amines. The salts obtained showed good effectiveness of the pre-sowing treatment of seeds of agricultural crops at concentrations of 20-40 mmol. In some cases, the seed treatment with salts leads not only to improved seed germination, but also to the suppression of microflora growth. Additionally, their anti-cancer activityin vitrohas been researched. The compounds with morpholine fragments or a fragment of N -dimethylpropylamine, demonstrated the highest cytotoxic activity, which is in good correlation with the ability to inhibit the glycolysis process in tumor cells. Two compounds 4e and 4g were selected for further experiments using laboratory animals. It was found that the lethal dose of 50% (LD 50 ) is 22.0 ± 1.33 mg/kg for 4e and 13.75 ± 1.73 mg/kg for 4g , i.e., compound 4e is two times less toxic than 4g, according to the mouse model in vivo. It was shown that the studied compounds exhibit antileukemia activity after a single intraperitoneal injection at doses from 1.25 to 5 mg/kg, as a result of which the average lifespan of animals with a P388 murine leukemia tumor increases from 20 to 28%. Thus, the water-soluble salts of benzofuroxans can be considered as promisingcandidates for further development, both as anti-cancer agents and as stimulants for seed germination and regulators of microflora crop growth.

FeCo and FeNi nanoalloy particles encapsulated in a nitrogen-doped carbonized shell (FeCo/C-N and FeNi/C-N) were synthesized by thermolysis at 400 °C of polyacrylamide complexes after frontal polymerization of co-crystallizate of Fe and Co or Ni nitrates and acrylamide. During the thermolysis of polyacrylamide complexes in a self-generated atmosphere, Co(II) or Ni(II) and Fe(III) cations are reduced to form FeCo and FeNi nanoalloy particles, while polyacrylamide simultaneously forms a nitrogen-doped carbon shell layer. This unique architecture provides high chemical and thermal stability of the resulting nanocomposites. The average crystallite size of FeCo and FeNi nanoparticles is 10 and 12 nm, respectively. The nanocomposites were studied by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. The nanocomposites have been tested as antifriction and antiwear additives in lubricating oils. The optimal concentrations of nanoparticles were determined, at which the antifriction and antiwear properties of the lubricant manifest themselves in the best possible way.

The formation and the spectroscopic and structural properties of 1:1 and 2:1 (ligand-to-dication) complexes of an (18-crown-6)stilbene with ethane-1,2-diammonium diperchlorate in MeCN were studied by UV-vis and NMR spectroscopy and by density functional theory calculations. Prolonged UV irradiation of 2:1 mixtures of the crown stilbene and the diammonium salt led to the formation of two main photoproducts, namely, the single syn -"head-to-head" photodimer of the crown stilbene ( rctt cyclobutane) due to supramolecular-assisted [2 + 2] photocycloaddition and a crown ether derivative of phenanthrene due to a photoinduced electrocyclization reaction. The rctt cyclobutane was isolated by preparative photolysis, followed by chromatography. The selectivity of the [2 + 2] photocycloaddition is explained by supramolecular pre-organization of crown stilbene molecules into the 2:1 complexes that have a pseudo-sandwich structure with stacking interactions between the stilbene moieties., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

The formation and accumulation of unfolded, misfolded, or damaged cellular proteins leads to development of endoplasmic reticulum stress (ER stress). A series of protective reactions is initiated in response to ER stress. These reactions are aimed at restoring the balance between protein synthesis and degradation, which is key to maintaining protein homeostasis (proteostasis). The main protective mechanisms are the attenuation of protein synthesis, increase of chaperone levels, and activation of protein degradation systems. Insufficiency or malfunction of these mechanisms induce apoptosis. Proteostasis dysregulation accompanied by protein aggregation and subsequent cell death in specific regions of the nervous system is a common pathogenetic hallmark of most neurodegenerative diseases. We discuss targeted regulation of the ER stress signaling pathways as a potential therapeutic strategy that can slow or even halt the disease progression.

A novel method has been proposed for rapid determination of principal transmembrane transport parameters for solute electroactive co-ions/molecules, in relation to the crossover problem in power sources. It is based on direct measurements of current for the electrode, separated from solution by an ion-exchange membrane, under voltammetric and chronoamperometric regimes. An electroactive reagent is initially distributed within the membrane/solution space under equilibrium. Then, potential change induces its transformation into the product at the electrode under the diffusion-limited regime. For the chronoamperometric experiment, the electrode potential steps backward after the current stabilization, thus inducing an opposite redox transformation. Novel analytical solutions for nonstationary concentrations and current have been derived for such two-stage regime. The comparison of theoretical predictions with experimental data for the Br 2 /Br - redox couple (where only Br - is initially present) has provided the diffusion coefficients of the Br - and Br 2 species inside the membrane, D(Br - ) = (2.98 ± 0.27) 10 -6 cm 2 /s and D(Br 2 ) = (1.10 ± 0.07) 10 -6 cm 2 /s, and the distribution coefficient of the Br - species at the membrane/solution boundary, K(Br - ) = 0.190 ± 0.005, for various HBr additions (0.125-0.75 M) to aqueous 2 M H 2 SO 4 solution. This possibility to determine transport characteristics of two electroactive species, the initial solute component and its redox product, within a single experiment, represents a unique feature of this study.

Alzheimer's disease (AD) is considered a modern epidemic because of its increasing prevalence worldwide and serious medico-social consequences, including the economic burden of treatment and patient care. The development of new effective therapeutic agents for AD is one of the most urgent and challenging tasks. To address this need, we used an aminoalkylene linker to combine the well-known anticholinesterase drug tacrine with antioxidant 2-tolylhydrazinylidene-1,3-diketones to create 3 groups of hybrid compounds as new multifunctional agents with the potential for AD treatment. Lead compounds of the new conjugates effectively inhibited acetylcholinesterase (AChE, IC 50 0.24-0.34 µM) and butyrylcholinesterase (BChE, IC 50 0.036-0.0745 µM), with weak inhibition of off-target carboxylesterase. Anti-AChE activity increased with elongation of the alkylene spacer, in agreement with molecular docking, which showed compounds binding to both the catalytic active site and peripheral anionic site (PAS) of AChE, consistent with mixed type reversible inhibition. PAS binding along with effective propidium displacement suggest the potential of the hybrids to block AChE-induced β-amyloid aggregation, a disease-modifying effect. All of the conjugates demonstrated metal chelating ability for Cu 2+ , Fe 2+ , and Zn 2+ , as well as high antiradical activity in the ABTS test. Non-fluorinated hybrid compounds 6 and 7 also showed Fe 3+ reducing activity in the FRAP test. Predicted ADMET and physicochemical properties of conjugates indicated good CNS bioavailability and safety parameters acceptable for potential lead compounds at the early stages of anti-AD drug development., Competing Interests: The authors declare no conflicts of interest.

The yellow fever virus (YFV) is an emerging RNA virus and has caused large outbreaks in Africa and Central and South America. The virus is often transmitted through infected mosquitoes and spreads from area to area because of international travel. Being an acute viral hemorrhagic disease, yellow fever can be prevented by an effective, safe, and reliable vaccine, but not be eliminated. Currently, there is no antiviral drug available for its cure. Thus, two series of novel bis(benzofuran−1,3-imidazolidin-4-one)s and bis(benzofuran−1,3-benzimidazole)s were designed and synthesized for the development of anti-YFV lead candidates. Among 23 new bis-conjugated compounds, 4 of them inhibited YFV strain 17D (Stamaril) on Huh-7 cells in the cytopathic effect reduction assays. These conjugates exhibited the most compelling efficacy and selectivity with an EC50 of <3.54 μM and SI of >15.3. The results are valuable for the development of novel antiviral drug leads against emerging diseases.

Among the different graphene derivatives, graphene oxide is the most intensively studied material as it exhibits reliable and repeatable resistive switching. The operative mechanisms that are responsible for resistive switching are being intensively investigated, and three models explaining the change in the resistive states have been developed. These models are grounded in the metallic-like filamentary conduction, contact resistance modification and the oxidation of/reduction in the graphene oxide bulk. In this work, using Al/GO/n-Si structures, we demonstrate that all three of these operative mechanisms can simultaneously participate in the resistive switching of graphene oxide. Multiple point-like conduction channels in the graphene oxide films were detected by the electron beam-induced current (EBIC) technique. At the same time, large areas with increased conductivity were also revealed by EBIC. An analysis of these areas by Raman spectroscopy indicates the change in the graphene oxide bulk's resistive properties. The EBIC data along with the measurements of the capacitance-voltage characteristics provided strong evidence of the involvement of an aluminum/graphene oxide interface in the switching processes. In addition, by using Al/GO/n-Si structures, we were able to identify unique local properties of the formed conductive channels, namely the change of the charge state of a conductive channel due to the creation of negatively charged traps and/or an increase in the GO work function.

Using the methodology of "click" chemistry, a series of conjugates of 3,5-bis(benzylidene)-1-(prop-2-yn)piperidin-4-ones with 4-alkyl-3-azidomethyl-2-ethoxy-2,5-dihydro-5H-1,2 oxaphosphol 2-oxides was synthesized. All newly obtained compounds 8-18 were characterized by 1 H, 13 C, 31 P, 19 F NMR and IR spectroscopy. The potential antitumor activity of the synthesized conjugates8-18was studied in terms of their ability to influence the viability of variouscancercell lines, including A549, SH-SY5Y, Hep-2, and HeLa. Compound 15, which contains two fluorine atoms in the benzene ring, was shown to be the most promising. The mechanism of the cytotoxic action of this conjugate is supposed to be associated with the ability to inhibit the glycolytic profile of transformed cells., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A novel biphotochromic dyad with styrylbenzo[ f ]quinoline photochromes was designed and synthesized to study the [2+2] photocycloaddition (PCA) reaction leading to cyclobutane with two benzo[ f ]quinoline (BQ) substituents and the reverse four-membered ring opening reaction. In the dyad, PCA occurs in a concerted manner according to the Woodward-Hoffmann rules in the ππ* excited state after excitation of the whole conjugated π-system comprising the ethylene group. Nanosecond time-resolved emission spectroscopy indicated formation of an excimer as a possible intermediate of the PCA reaction. The reverse reaction of photoinduced cyclobutane ring opening is assumed to proceed stepwise according to the predissociation mechanism: after excitation of the BQ substituent, energy transfer (ET) occurs from the bonding ππ* term localized on the BQ substituent to the dissociative πσ* term localized on cyclobutane; the efficiency of such a process was measured for the first time. For the first time, it is suggested that the predissociation mechanism is common to the ring-opening reaction of any cyclobutane with an unsaturated substituent where the π-system of the substituent rather than the σ-system of cyclobutane is excited under light irradiation.

While potentiometric, plasticized membrane sensors are known as convenient, portable and inexpensive analytical instruments, their development is time- and resource-consuming, with a poorly predictable outcome. In this study, we investigated the applicability of the QSPR (quantitative structure-property relationship) method for predicting the potentiometric sensitivity of plasticized polymeric membrane sensors, using the ionophore chemical structure as model input. The QSPR model was based on the literature data on sensitivity, from previously studied, structurally similar ionophores, and it has shown reasonably good metrics in relating ionophore structures to their sensitivities towards Cu 2+ , Cd 2+ and Pb 2+ . The model predictions for four newly synthesized diphenylphosphoryl acetamide ionophores were compared with real potentiometric experimental data for these ionophores, and satisfactory agreement was observed, implying the validity of the proposed approach.

Brush-like elastomers with crystallizable side chains hold promise for biomedical applications requiring the presence of two distinct mechanical states below and above body temperature: hard and supersoft. The hard semicrystalline state facilitates piercing of the body whereupon the material softens to match the mechanics of surrounding soft tissue. To understand the transition between the two states, the crystallization process was studied with synchrotron X-ray scattering for a series of brush elastomers with poly(ε-caprolactone) side chains bearing from 7 to 13 repeat units. The so-called bottlebrush correlation peak was used to monitor configuration of bottlebrush backbones in the amorphous regions during the crystallization process. In the course of crystallization, the backbones are expelled into the interlamellar amorphous gaps, which is accompanied by their conformational changes and leads to partitioning to unconfined (melt) and confined (semicrystalline) (conformational) states. The crystallization process starts by consumption of the unconfined macromolecules by the growing crystals followed by reconfiguration of macromolecules within the already grown spherulites.

Cellulose HogC was produced by the modified traditional method with 35% yield from the stem of Sosnovsky hogweed and was characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffractometry, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). For HogC , the degree of crystallinity (approximately 70%) and the glass transition temperature (105-108 °C) were determined. It was found that the whiteness characteristic in the case of HogC was 92% and this significate was obtained without a bleaching procedure using chlorine-containing reagents. In this paper, the possibility of hydrophobization of HogC films by treatment with radiation-synthesized telomers of tetrafluoroethylene is shown. It was found that the contact angle of the telomer-treated cellulose film surface depended on the properties of the telomers (the chemical nature of the solvent, and the initial concentration of tetrafluoroethylene) and could reach 140 degrees.

To adjust the thermal safety of hydrophobic silica aerogel, layered double hydroxide (LDH)/silica aerogel (SA) composites were prepared by an in-situ sol-gel process at ambient pressure. This study found the physical combination of SA and MgAl-LDH based on the FTIR spectra and phase composition of LDH/SA. The N 2 sorption analysis confirms that the introduction of MgAl-LDH does not change the mesoporous attribution of LDH/SA significantly. With the increase in MgAl-LDH addictive content, the low density (0.12-0.13 g/cm 3 ), low thermal conductivity (24.28-26.38 mW/m/K), and large specific surface area (730.7-903.7 m 2 g) of LDH/SA are still maintained, which can satisfy the requirements of thermal insulation. The TG-DSC analysis demonstrates that the endothermic effects and metal oxides formed during the MgAl-LDH decomposition are beneficial to the improvement of the thermal stability of LDH/SA composites. In addition, it was found that the gross calorific values of LDH/SA composites decrease with an increase in MgAl-LDH addictive content, all of which are lower than that of the pure SA. The research outcomes indicate that the thermal safety of LDH/SA composites is enhanced significantly by doping MgAl-LDH without impairing too many of the excellent properties, which benefits their expansion in the thermal insulation field.

Background: The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19) triggers the development of numerous pathologies and infection-linked complications and exacerbates existing pathologies in nearly all body systems. Aside from the primarily targeted respiratory organs, adverse SARS-CoV-2 effects were observed in nervous, cardiovascular, gastrointestinal/metabolic, immune, and other systems in COVID-19 survivors. Long-term effects of this viral infection have been recently observed and represent distressing sequelae recognised by the World Health Organisation (WHO) as a distinct clinical entity defined as post-COVID-19 condition. Considering the pandemic is still ongoing, more time is required to confirm post COVID-19 condition diagnosis in the COVID-19 infected cohorts, although many reported post COVID-19 symptoms overlap with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)., Aims of Review: In this study, COVID-19 clinical presentation and associated post-infection sequelae (post-COVID-19 condition) were reviewed and compared with ME/CFS symptomatology., Key Scientific Concepts of Review: The onset, progression, and symptom profile of post COVID-19 condition patients have considerable overlap with ME/CFS. Considering the large scope and range of pro-inflammatory effects of this virus, it is reasonable to expect development of post COVID-19 clinical complications in a proportion of the affected population. There are reports of a later debilitating syndrome onset three months post COVID-19 infection (often described as long-COVID-19), marked by the presence of fatigue, headache, cognitive dysfunction, post-exertional malaise, orthostatic intolerance, and dyspnoea. Acute inflammation, oxidative stress, and increased levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNFα), have been reported in SARS-CoV-2 infected patients. Longitudinal monitoring of post COVID-19 patients is warranted to understand the long-term effects of SARS-CoV-2 infection and the pathomechanism of post COVID-19 condition., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Production and hosting by Elsevier B.V.)

A power source based on the current-generating reaction of aqueous chlorate-to-chloride reduction by molecular hydrogen would provide as much as 1150 Wh per 1 L of reagent storage (for a combination of 700 atm compressed hydrogen and saturated aqueous solution of lithium chlorate) at room temperature, but direct electroreduction of chlorate only proceeds with unacceptably high overvoltages, even for the most catalytically active electrodes. In the present study, we experimentally demonstrated that this process can be performed via redox-mediator catalysis by intermediate products of chlorate reduction, owing to their participation in homogeneous com- and disproportionation reactions. A series of current-voltage and discharge characteristics were measured for hydrogen-chlorate membrane-electrode assembly (MEA) cells at various concentrations of chlorate and sulfuric acid under operando spectrophotometric monitoring of the electrolyte composition during the discharge. We established that chlorine dioxide (ClO 2 ) is the key intermediate product; its fraction in the electrolyte solution increases progressively, up to its maximum, equal to 0.4-0.6 of the initial amount of chlorate anions, whereas the ClO 2 amount decreases gradually to a zero value in the later stage. In most discharge experiments, the Faradaic yield exceeded 90% (maximal value: 99%), providing approximately 48% chemical energy storage-to-electricity conversion efficiency at maximal power of the discharge (max value: 402 mW/cm 2 ). These results support prospect of a hydrogen-chlorate flow current generator as a highly specific energy-capacity source for airless media.

Circular RNAs (circRNAs) are a class of single-stranded closed non-coding RNA molecules (ncRNAs), which are formed as a result of reverse splicing of mRNAs. Despite their relative abundance, an interest in understanding their regulatory importance is rather recent. High stability, abundance and evolutionary conservation among species underline some of their important traits. CircRNAs perform a variety of cellular functions ranging from miRNA and proteins sponges to transcriptional modulation and splicing. Additionally, most circRNAs are expressed aberrantly in pathological conditions suggesting their possible exploitation as diagnostic biomarkers. Their covalent closed cyclic structure resulting in resistance to RNases further makes them suitable as cancer biomarkers. Studies involving human tumors have verified differences in the expression profiles of circRNAs, indicating a regulatory role in cancer pathogenesis and metastasis. As endogenous competitive RNA, circRNAs can regulate tumor proliferation and invasion. Further, some circRNAs located in the nucleus can regulate transcription of genes by binding to RNA polymerase II. In this review, we elaborate the characteristics, functions and mechanisms of action of circRNAs in cancer. We also discuss the possibility of using circRNAs as potential therapeutic targets and biomarkers for cancer., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The first X-band EPR spectrum containing only non-overlapping signals of septet pyridyl-2,4,6-trinitrene and triplet pyridylnitrenes is reported. This spectrum was recorded after photolysis of 2,4,6-triazidopyridine in solid argon at 5 K. The zero-field splitting (ZFS) parameters of this trinitrene as well as of intermediate triplet mononitrenes and quintet dinitrenes formed at early stages of the photolysis were determined using the combination of modern computer line-shape spectral simulations and density functional theory (DFT) calculations. It was found that septet pyridyl-2,4,6-trinitrene has the record negative parameter D S  = -0.1031 cm -1 among all known to date septet pyridyl-2,4,6-trinitrenes and may be of interest as a model multi-qubit spin system for investigations of quantum computation processing., (© 2022 John Wiley & Sons, Ltd.)

Breast cancer (BC) cell de-sensitization to Tamoxifen (TAM) or other selective estrogen receptor (ER) modulators (SERM) is a complex process associated with BC heterogeneity and the transformation of ER signalling. The most influential resistance-related mechanisms include modifications in ER expression and gene regulation patterns. During TAM/SERM treatment, epigenetic mechanisms can effectively silence ER expression and facilitate the development of endocrine resistance. ER status is efficiently regulated by specific epigenetic tools including hypermethylation of CpG islands within ER promoters, increased histone deacetylase activity in the ER promoter, and/or translational repression by miRNAs. Over-methylation of the ER α gene (ESR1) promoter by DNA methyltransferases was associated with poor prognosis and indicated the development of resistance. Moreover, BC progression and spreading were marked by transformed chromatin remodelling, post-translational histone modifications, and expression of specific miRNAs and/or long non-coding RNAs. Therefore, targeted inhibition of histone acetyltransferases (e.g. MYST3), deacetylases (e.g. HDAC1), and/or demethylases (e.g. lysine-specific demethylase LSD1) was shown to recover and increase BC sensitivity to anti-estrogens. Indicated as a powerful molecular instrument, the administration of epigenetic drugs can regain ER expression along with the activation of tumour suppressor genes, which can in turn prevent selection of resistant cells and cancer stem cell survival. This review examines recent advances in the epigenetic regulation of endocrine drug resistance and evaluates novel anti-resistance strategies. Underlying molecular mechanisms of epigenetic regulation will be discussed, emphasising the utilization of epigenetic enzymes and their inhibitors to re-program irresponsive BCs., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases in existence. It is characterized by an impaired cognitive function that is due to a progressive loss of neurons in the brain. Extracellular β-amyloid (Aβ) plaques are the main pathological features of the disease. In addition to abnormal protein aggregation, increased mitochondrial fragmentation, altered expression of the genes involved in mitochondrial biogenesis, disruptions in the ER-mitochondria interaction, and mitophagy are observed. Reactive oxygen species are known to affect Aβ expression and aggregation. In turn, oligomeric and aggregated Aβ cause mitochondrial disorders. In this review, we summarize available knowledge about the pathological effects of Aβ on mitochondria and the potential molecular targets associated with proteinopathy and mitochondrial dysfunction for the pharmacological treatment of Alzheimer's disease., (Copyright ® 2022 National Research University Higher School of Economics.)

Objective: The cuticle of human hair has been examined, via a range of analytical methods, in order to reveal previously unknown information about its structure and to deepen understanding of its contribution to fibre properties., Methods: Cross-sections of hair fibre have been examined with X-ray microdiffraction oriented perpendicular to the surface of the cross-sections. AFM investigations were carried out for further investigating and deciphering the structure of the cuticle. Moisture sorption analytics of cuticle separated from fibre and mechanical tests of decuticled fibres against virgin fibres were used for understanding the role of the cuticle in the economy of hair fibre., Results: Previously unknown swelling behaviour of the hair cuticle during moisture sorption has been revealed, as has an increased significance of the cuticle's role in moisture management at higher values of relative humidity. Through AFM investigation, the reaction of hair cuticles with chlorine water has further strengthened the idea that the Allwörden membrane does not exist, and is actually an artefact of the delamination of the A-layer and exocuticle from the underlying endocuticle. Using decuticled fibres for stress-strain tests, and by comparing the results with those of virgin fibres, the effect of the cuticle on the post-yield area of the hair fibre stress-strain diagram has also been demonstrated. Finally, X-ray microdiffraction and AFM investigations suggest that the cuticle possesses a small-scale ordered structure, based on possibly not fully crystalline and irregularly arranged α-helices oriented almost perpendicular to the growth axis of the fibre and enhancing the general description of cuticle as the protective layer of the fibre., Conclusion: The role of the cuticle for the hair fibre is more complex than previously thought. The cuticle is demonstrated not only to possess a hidden rod-matrix structure, that supports its protective nature, but also to play specific roles in the fibre's response to moisture, and in fibre mechanical behaviour., (© 2022 Society of Cosmetic Scientists and the Société Française de Cosmétologie.)

Macrophages, the key cells of innate immunity, possess wide phenotypical and functional heterogeneity. In vitro studies showed that microenvironment signals could induce the so-called polarization of macrophages into two phenotypes: classically activated macrophages (M1) or alternatively activated macrophages (M2). Functionally, they are considered as proinflammatory and anti-inflammatory/pro-regenerative, respectively. However, in vivo studies into macrophage states revealed a continuum of phenotypes from M1 to M2 state instead of the clearly distinguished extreme phenotypes. An important role in determining the type of polarization of macrophages is played by energy metabolism, including the activity of oxidative phosphorylation. In this regard, hypoxia and ischemia that affect cellular energetics can modulate macrophage polarization. Here, we overview the data on macrophage polarization during metabolic shift-associated pathologies including ischemia and ischemia/reperfusion in various organs and discuss the role of energy metabolism potentially triggering the macrophage polarization.

The paper presents a program for simulating electron scattering in layered materials ProxyFn . Calculations show that the absorbed energy density is three-dimensional, while the contribution of the forward-scattered electrons is better described by a power function rather than the commonly used Gaussian. It is shown that for the practical correction of the proximity effect, it is possible, nevertheless, to use the classical two-dimensional proximity function containing three parameters: α, β, η. A method for determining the parameters α, β, η from three-dimensional calculations based on MC simulation and development consideration is proposed. A good agreement of the obtained parameters and experimental data for various substrates and electron energies is shown. Thus, a method for calculating the parameters of the classical proximity function for arbitrary layered substrates based on the Monte Carlo simulation has been developed.

Schizophrenia (SZ) is a chronic psychiatric disorder affecting several people worldwide. Mitochondrial DNA (mtDNA) variations could invoke changes in the OXPHOS system, calcium buffering, and ROS production, which have significant implications for glial cell survival during SZ. Oxidative stress has been implicated in glial cells-mediated pathogenesis of SZ; the brain comparatively more prone to oxidative damage through NMDAR. A confluence of scientific evidence points to mtDNA alterations, Nrf2 signaling, dynamic alterations in dorsolateral prefrontal cortex (DLPFC), and provocation of oxidative stress that enhance pathophysiology of SZ. Furthermore, the alterations in excitatory signaling related to NMDAR signaling were particularly reported for SZ pathophysiology. Current review reported the recent evidence for the role of mtDNA variations and oxidative stress in relation to pathophysiology of SZ, NMDAR hypofunction, and glutathione deficiency. NMDAR system is influenced by redox dysregulation in oxidative stress, inflammation, and antioxidant mediators. Several studies have demonstrated the relationship of these variables on severity of pathophysiology in SZ. An extensive literature search was conducted using Medline, PubMed, PsycINFO, CINAHL PLUS, BIOSIS Preview, Google scholar, and Cochrane databases. We summarize consistent evidence pointing out a plausible model that may elucidate the crosstalk between mtDNA alterations in glial cells and redox dysregulation during oxidative stress and the perturbation of NMDA neurotransmitter system during current therapeutic modalities for the SZ treatment. This review can be beneficial for the development of promising novel diagnostics, and therapeutic modalities by ascertaining the mtDNA variations, redox state, and efficacy of pharmacological agents to mitigate redox dysregulation and augment NMDAR function to treat cognitive and behavioral symptoms in SZ., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objectives: The development of compact diagnostic probes and instruments with an ability to direct access to organs and tissues and integration of these instruments into surgical workflows is an important task of modern physics and medicine. The need for such tools is essential for surgical oncology, where intraoperative visualization and demarcation of tumor margins define further prognosis and survival of patients. In this paper, the possible solution for this intraoperative imaging problem is proposed and its feasibility to detect tumorous tissue is studied experimentally., Methods: For this aim, the sapphire scalpel was developed and fabricated using the edge-defined film-fed growth technique aided by mechanical grinding, polishing, and chemical sharpening of the cutting edge. It possesses optical transparency, mechanical strength, chemical inertness, and thermal resistance alongside the presence of the as-grown hollow capillary channels in its volume for accommodating optical fibers. The rounding of the cutting edge exceeds the same for metal scalpels and can be as small as 110 nm. Thanks to these features, sapphire scalpel combines tissue dissection with light delivering and optical diagnosis. The feasibility for the tumor margin detection was studied, including both gelatin-based tissue phantoms and ex vivo freshly excised specimens of the basal cell carcinoma from humans and the glioma model 101.8 from rats. These tumors are commonly diagnosed either non-invasively or intraoperatively using different modalities of fluorescence spectroscopy and imaging, which makes them ideal candidates for our feasibility test. For this purpose, fiber-based spectroscopic measurements of the backscattered laser radiation and the fluorescence signals were carried out in the visible range., Results: Experimental studies show the feasibility of the proposed sapphire scalpel to provide a 2-mm-resolution of the tumor margins' detection, along with an ability to distinguish the tumor invasion region, which results from analysis of the backscattered optical fields and the endogenous or exogenous fluorescence data., Conclusions: Our findings justified a strong potential of the sapphire scalpel for surgical oncology. However, further research and engineering efforts are required to optimize the sapphire scalpel geometry and the optical diagnosis protocols to meet the requirements of oncosurgery, including diagnosis and resection of neoplasms with different localizations and nosologies., (© 2021 Wiley Periodicals LLC.)

We report new insights into the ultrafast rearrangement and dissociation dynamics of nitromethane cation (NM + ) using pump-probe measurements, electronic structure calculations, and ab initio molecular dynamics simulations. The "roaming" nitro-nitrite rearrangement (NNR) pathway involving large-amplitude atomic motion, which has been previously described for neutral nitromethane, is demonstrated for NM + . Excess energy resulting from initial population of the electronically excited D 2 state of NM + upon strong-field ionization provides the necessary energy to initiate NNR and subsequent dissociation into NO + . Both pump-probe measurements and molecular dynamics simulations are consistent with the completion of NNR within 500 fs of ionization with dissociation into NO + and OCH 3 occurring ∼30 fs later. Pump-probe measurements indicate that NO + formation is in competition with the direct dissociation of NM + to CH 3 + and NO 2 . Electronic structure calculations indicate that a strong D 0 transition can be excited at 650 nm when the C-N bond is stretched from its equilibrium value (1.48 Å) to 1.88 Å. On the other hand, relaxation of the NM 1 transition can be excited at 650 nm when the C-N bond is stretched from its equilibrium value (1.48 Å) to 1.88 Å. On the other hand, relaxation of the NM + occurs in less than 50 fs and results in observation of intact NM 0 . Direct dissociation of the equilibrium NM + . Direct dissociation of the equilibrium NM + to produce NO 2 + and CH 3 can be induced with 650 nm excitation via a weakly allowed D 0 → D 2 transition.

We present complex spectroscopic data of the synthetic brunogeierite (Fe 2+ ) 2 Ge 4+ O 4 with space group Fd3¯m of spinel structure: a = 8.3783 (6) Å, V = 588.12 (13) Å 3 . Brunogeierite crystals up to 200 μm in size were crystallized by the interaction of a boric acid solution on a metal iron wire in the presence of germanium oxide (GeO 2 ) at 600/650 °C and 100 MPa. Mössbauer spectrum of synthetic brunogeierite consists of the symmetric doublet with the parameters IS = 1.104(1) mm/s and QS = 2.845(1) mm/s, that corresponds to the octahedral position of iron ions ( [VI] Fe 2+ ). The Raman spectra of Fe 2 GeO 4 crystal consist of an intense main band at 756 cm -1 and four less intense bands at ∼644, 472, 302, and ∼205 cm -1 at ambient conditions. All five bands inherent in the spectrum of cubic spinel are present and gradual change in high pressure spectra up to 30 GPa. The color of the crystal changes from brown-orange to reddish at the center at 22.7 GPa and became opaque black up to 30.2 GPa. Herewith, in the high pressure spectra, we observed the splitting of some bands and the appearance of additional bands in a wide pressure range (from 1.6 to 30 GPa). The factor group analysis with the lattice dynamics calculation of potential crystal structure distortions shows the decreasing of the structure symmetry to tetragonal or rhombohedral in this pressure range., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A novel multi-chromophoric system, triad, in which two styrylbenzoquinoline (SBQ) photochromes are connected by a balanced rigid-flexible linker comprising 2,3-naphthylene framework (a residue of 3-oxy-2-naphthoic acid) and tetramethylene groups, was designed and synthesized to study an excimer formation in the excited state. The 1 H NMR data testified that triad exists in solution as folded conformers with asymmetric parallel-displaced SBQ units. Under light irradiation, in the triad, competitive photoisomerization and [2 + 2] photocycloaddition reactions were observed, both reactions being reversible. The photocycloaddition resulted in a tetrasubstituted cyclobutane. The red-shifted fluorescence spectrum and the appearance of a long-lived component in the triad fluorescence decay indicated formation of an 'emissive' excimer. The photocycloaddition is assumed to occur in a 'reactive' excimer, in which the ethylene groups of the SBQ photochromes are located at a distance sufficient for the formation of the σ-bonds between them. Quantum-chemical density functional theory (DFT) calculations at M06-2X/6-31G* level predicted the existence of the triad conformers with π-stacking interaction of SBQ photochromes, the structure of which is pre-organized for the excimer formation and photocycloaddition. For the first time, both emissive and reactive excimers were experimentally observed in the multi-chromophoric system with two diarylethylene photochromes undergoing [2 + 2] photocycloaddition., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Topological analysis of the heteropolyhedral MT framework (where M and T are octahedral and tetrahedral cations, respectively) in the eudialyte-type structure and its derivatives was performed based on a natural tiling analysis of the 3D cation. To analyze the migration paths of sodium cations in these structures, the Voronoi method was used. The parental eudialyte-type MT framework is formed by isolated ZO 6 octahedra, six-membered [M(1) 6 O 24 ] rings of edge-sharing M(1)O 6 octahedra, and two kinds of rings of tetrahedra, [Si 3 O 9 ] and [Si 9 O 27 ]. Different occupancies of M(2), M(3) and M(4) sites with variable coordination numbers by the additional Q, T* and M* cations, respectively, result in 12 different types of the MT framework. Based on the results of natural tilings calculations as well as theoretical analysis of migration paths, it is found that Na + ions can migrate through six- and seven-membered rings, while all other rings are too small for the migration. In eight types of MT frameworks, Na + -ion migration and diffusion is possible at ambient temperature and pressure, while in four other types cages are connected by narrow windows and, as a result, the Na + diffusion in them is complicated at ambient conditions because of the window diameter, but may be possible either at higher temperatures or under mild geological conditions for long periods of time.

Injectable hydrogels are desired in many biomedical applications due to their minimally invasive deployment to the body and their ability to introduce drugs. However, current injectables suffer from mechanical mismatch with tissue, fragility, water expulsion, and high viscosity. To address these issues, we design brush-like macromolecules that concurrently provide softness, firmness, strength, fluidity, and swellability. The synthesized linear-bottlebrush-linear (LBL) copolymers facilitate improved injectability as the compact conformation of bottlebrush blocks results in low solution viscosity, while the thermoresponsive linear blocks permit prompt gelation at 37°C. The resulting hydrogels mimic the deformation response of supersoft tissues such as adipose and brain while withstanding deformations of 700% and precluding water expulsion upon gelation. Given their low cytotoxicity and mild inflammation in vivo, the developed materials will have vital implications for reconstructive surgery, tissue engineering, and drug delivery applications.

Layered tin selenide (SnSe) has recently emerged as a high-performance thermoelectric material with the current record for the figure of merit ( ZT ) observed in the high-temperature Cmcm phase. So far, access to the Cmcm phase has been mainly obtained via thermal equilibrium methods based on sample heating or application of external pressure, thus restricting the current understanding only to ground-state conditions. Here, we investigate the ultrafast carrier and phononic dynamics in SnSe. Our results demonstrate that optical excitations can transiently switch the point-group symmetry of the crystal from Pnma to Cmcm at room temperature in a few hundreds of femtoseconds with an ultralow threshold for the excitation carrier density. This nonequilibrium Cmcm phase is found to be driven by the displacive excitation of coherent A g phonons and, given the absence of low-energy thermal phonons, exists in SnSe with the status of 'cold lattice with hot carriers'. Our findings provide an important insight for understanding the nonequilibrium thermoelectric properties of SnSe.

Background: Ionizing Radiation (IR) is one of the major limiting factors for human deep-space missions. Preventing IR-induced cognitive alterations in astronauts is a critical success factor. It has been shown that cognitive alterations in rodents can be inferred by alterations of a psycho- emotional balance, primarily an anxiogenic effect of IR. In our recent work, we hypothesized that the neurokinin-1 (NK1) receptor might be instrumental for such alterations., Objective: The NK1 receptor antagonist rolapitant and the classic anxiolytic diazepam (as a comparison drug) were selected to test this hypothesis on Wistar rats., Methods: Pharmacological substances were administered through intragastric probes. We used a battery of tests for a comprehensive ethological analysis. High-performance liquid chromatography was applied to quantify monoamines content. An analysis of mRNA expression was performed by real-time PCR. Protein content was studied by the Western blotting technique., Results: Our salient finding includes no substantial changes in anxiety, locomotor activity and cognitive abilities of treated rats under irradiation. No differences were found in the content of monoamines. We discovered a synchronous effect on mRNA expression and protein content of 5- HT2a and 5-HT4 receptors in the prefrontal cortex, as well as decreased content of serotonin transporter and increased content of tryptophan hydroxylase in the hypothalamus of irradiated rats. Rolapitant affected the protein amount of a number of serotonin receptors in the amygdala of irradiated rats., Conclusion: Rolapitant may be the first atypical radioprotector, providing symptomatic treatment of CNS functional disorders in astronauts caused by IR., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In this article, we present a critical discussion of the parametric regimes required for reaching the functionality of the two-electron square-planar tetrameric mixed-valence (MV) complexes as molecular cells in quantum cellular automata (QCA). Previous studies on molecular QCA were restricted by the limit case of strong Coulomb interaction that was supposed to be the only way to ensure such two key requirements for functioning QCA cells as bistability and switchability. It was thus assumed that the site-to-site electron transfer energy t should be much smaller than the energy U of the Coulomb repulsion between the two excess electrons (strong- U limit defined by the inequality U ≫ t ). Unlike those studies, here, we develop a generalized theoretical approach within which no restricting assumptions are implied on the relative strength of the intracell Coulomb interaction, electron transfer, the vibronic coupling with "breathing" modes of redox sites and the external electrostatic field of the driver cell acting on the working cell. We demonstrate that dominating Coulomb repulsion is not the only source of bistability and switchability, but such key features of QCA cell can be reached even in systems in which the strong- U limit is violated, provided that the vibronic coupling is strong enough. Such a reconsideration of the parameter regime for achieving proper functionality is expected to essentially enlarge the family of MV molecules, which can be used as molecular QCA cells.

The binding of aminoxyls to polymers extends their potential use as antioxidants and EPR-reporting groups and opens up new horizons for tailoring new smart materials. In this work, we synthesized and characterized non-sulfated and N-sulfated water-soluble amphiphilic chitosans with a critical micelle concentration of 0.02-0.05 mg/mL that contain 13-18% of aminoglycosides bound with various aminoxyls. Chitosan-polyaminoxyls (CPAs) formed micelles with hydrodynamic radii R h of ca. 100 nm. The EPR spectra of CPAs were found to depend on the rigidity of the aminoxyl-polymer bond and structural changes caused by sulfation. CPAs demonstrated antioxidant capacity/activity in three tests against reactive oxygen species (ROS) of various nature. The charge of micelles and structure of aminoxyls significantly affected their antioxidant properties. CPAs were low toxic against tumor (HepG2, HeLa, A-172) and non-cancerous (Vero) cells (IC 50  > 0.8 mM of aminoglycosides). Sulfated CPAs showed better water solubility and the ability of binding and retaining the anti-tumor antibiotic daunorubicin (DAU). DAU-loaded micelles of CPAs (CPAs-DAU) demonstrated a 1.5-4-fold potentiation of DAU cytotoxicity against several cell lines. CPAs-DAU micelles were found to affect the cell cycle in a manner markedly different from that of free DAU. Our results demonstrated the ability of CPAs to act as bioactive drug delivery vehicles., (Copyright © 2021 Elsevier B.V. All rights reserved.)

We report measurements of the saturated intensities, saturable absorption, and nonlinear refraction in 70-nm thick films containing 4 nm HgTe quantum dots. We demonstrate strong nonlinear refraction and saturable absorption in the thin films using tunable picosecond and femtosecond pulses. Studies were carried out using tunable laser pulses in the range of 400-1100 nm. A significant variation of the nonlinear refraction along this spectral range was demonstrated. The maximal values of the nonlinear absorption coefficients and nonlinear refractive indices determined within the studied wavelength range were -2.4 × 10 -5 cm 2 W -1 (in the case of 28 ps, 700 nm probe pulses) and -3 × 10 -9 cm 2 W -1 (in the case of 28 ps, 400 nm probe pulses), respectively. Our studies show that HgTe quantum dots can be used in different fields e.g., as efficient emitters of high-order harmonics of ultrashort laser pulses or as laser mode-lockers.

We measured the level of natural antibodies (nAb) to glutamate and GABA reflecting the balance of excitation and inhibition systems and involved in the adaptation processes in athletes receiving normalized physical activity in the dynamics of training (figure skaters, football players, and people actively involved in sports). It was found that each subject has an individual immunological profile and its parameters change in accordance with the training load. The measured levels of nAbs to GABA and glutamate correlate the physical activity of a person. The surveyed football players were divided into 3 groups according to the results of the analysis. Subjects of the first group had reliably high immunological indices in comparison with the control and were at the peak of physical form; in the third group, low immunological indices relative to the control indicated exhaustion and fatigue. The indicators of the second group corresponded to normal and demonstrated the resource of adaptation to load. The developed method can be used for assessing person's readiness for physical activity., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Synucleins, a family of three proteins highly expressed in neurons, are predominantly known for the direct involvement of α-synuclein in the etiology and pathogenesis of Parkinson's and certain other neurodegenerative diseases, but their precise physiological functions are still not fully understood. Previous studies have demonstrated the importance of α-synuclein as a modulator of various mechanisms implicated in chemical neurotransmission, but information concerning the involvement of other synuclein family members, β-synuclein and γ-synuclein, in molecular processes within presynaptic terminals is limited. Here, we demonstrated that the vesicular monoamine transporter 2-dependent dopamine uptake by synaptic vesicles isolated from the striatum of mice lacking β-synuclein is significantly reduced. Reciprocally, reintroduction, either in vivo or in vitro, of β-synuclein but not α-synuclein or γ-synuclein improves uptake by triple α/β/γ-synuclein-deficient striatal vesicles. We also showed that the resistance of dopaminergic neurons of the substantia nigra pars compacta to subchronic administration of the Parkinson's disease-inducing prodrug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine depends on the presence of β-synuclein but only when one or both other synucleins are absent. Furthermore, proteomic analysis of synuclein-deficient synaptic vesicles versus those containing only β-synuclein revealed differences in their protein compositions. We suggest that the observed potentiation of dopamine uptake by β-synuclein might be caused by different protein architecture of the synaptic vesicles. It is also feasible that such structural changes improve synaptic vesicle sequestration of 1-methyl-4-phenylpyridinium, a toxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, which would explain why dopaminergic neurons expressing β-synuclein and lacking α-synuclein and/or γ-synuclein are resistant to this neurotoxin., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

An approach to obtaining various nanostructures utilizing a well-studied polystyrene- b -poly(isoprene) or PS- b -PI diblock copolymer system through chemical modification reactions is reported. The complete hydrogenation and partial sulfonation to the susceptible carbon double bonds of the PI segment led to the preparation of [polystyrene- b -poly(ethylene- alt -propylene)] as well as [polystyrene- b -poly(sulfonated isoprene- co -isoprene)], respectively. The hydrogenation of the polyisoprene block results in enhanced segmental immiscibility, whereas the relative sulfonation induces an amphiphilic character in the final modified material. The successful synthesis of the pristine diblock copolymer through anionic polymerization and the relative chemical modification reactions were verified using several molecular and structural characterization techniques. The thin film structure-properties relationship was investigated using atomic force microscopy under various conditions such as different solvents and annealing temperatures. Small-angle X-ray scattering was employed to identify the different observed nanostructures and their evolution upon thermal annealing.

Two-dimensional electron systems in a quantizing magnetic field are regarded as of exceptional interest, considering the possible role of anyons-quasiparticles with non-boson and non-fermion statistics-in applied physics. To this day, essentially none but the fractional states of the quantum Hall effect (FQHE) have been experimentally realized as a system with anyonic statistics. In determining the thermodynamic properties of anyon matter, it is crucial to gain insight into the physics of its neutral excitations. We form a macroscopic quasi-equilibrium ensemble of neutral excitations - spin one anyon complexes in the Laughlin state ν = 1/3, experimentally, where ν is the electron filling factor. The ensemble is found to have such a long lifetime that it can be considered the new state of anyon matter. The properties of this state are investigated by optical techniques to reveal its Bose properties., (© 2021. The Author(s).)

Synthesis, spectral properties, and photodynamic activity of water-soluble amino acid fullerene C 60 derivatives (AFD) and four original AFD-PPa dyads, obtained by covalent addition of dye pyropheophorbide (PPa) to AFD, were studied. In aqueous solution, these AFD-PPa dyads form nanoassociates as a result of self-assembly. In this case, a significant change in the absorption spectra and strong quenching of the dye fluorescence in the structure of the dyads were observed. A comparison of superoxide or singlet oxygen generation efficiency of the studied compounds in an aqueous solution showed the photodynamic mechanism switching from type II (singlet oxygen generation of the native dye) to I type (superoxide generation of dyads). All dyads have pronounced phototoxicity on cells Hela with IC 50 9.2 µM, 9.2 µM, 12.2 µM for dyads Val-C 60 -PPa, Ala-C 60 -PPa and Pro-C 60 -PPa, respectively. Such facilitation of type I photodynamic mechanism could be perspective against hypoxic tumors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

Partial melting of mantle peridotites at spreading ridges is a continuous global process that forms the oceanic crust and refractory, positively buoyant residues (melt-depleted mantle peridotites). In the modern Earth, these rocks enter subduction zones as part of the oceanic lithosphere. However, in the early Earth, the melt-depleted peridotites were 2-3 times more voluminous and their role in controlling subduction regimes and the composition of the upper mantle remains poorly constrained. Here, we investigate styles of lithospheric tectonics, and related dynamics of the depleted mantle, using 2-D geodynamic models of converging oceanic plates over the range of mantle potential temperatures (T p  = 1300-1550 °C, ∆T = T - T modern  = 0-250 °C) from the Archean to the present. Numerical modeling using prescribed plate convergence rates reveals that oceanic subduction can operate over this whole range of temperatures but changes from a two-sided regime at ∆T = 250 °C to one-sided at lower mantle temperatures. Two-sided subduction creates V-shaped accretionary terrains up to 180 km thick, composed mainly of highly hydrated metabasic rocks of the subducted oceanic crust, decoupled from the mantle. Partial melting of the metabasic rocks and related formation of sodic granitoids (Tonalite-Trondhjemite-Granodiorite suites, TTGs) does not occur until subduction ceases. In contrast, one sided-subduction leads to volcanic arcs with or without back-arc basins. Both subduction regimes produce over-thickened depleted upper mantle that cannot subduct and thus delaminates from the slab and accumulates under the oceanic lithosphere. The higher the mantle temperature, the larger the volume of depleted peridotites stored in the upper mantle. Extrapolation of the modeling results reveals that oceanic plate convergence at ∆T = 200-250 °C might create depleted peridotites (melt extraction of > 20%) constituting more than half of the upper mantle over relatively short geological times (~ 100-200 million years). This contrasts with the modeling results at modern mantle temperatures, where the amount of depleted peridotites in the upper mantle does not increase significantly with time. We therefore suggest that the bulk chemical composition of upper mantle in the Archean was much more depleted than the present mantle, which is consistent with the composition of the most ancient lithospheric mantle preserved in cratonic keels., (© 2021. The Author(s).)

Pathological changes involving TDP-43 protein ('TDP-43 proteinopathy') are typical for several neurodegenerative diseases, including frontotemporal lobar degeneration (FTLD). FTLD-TDP cases are characterized by increased binding of TDP-43 to an abundant lncRNA, NEAT1, in the cortex. However it is unclear whether enhanced TDP-43-NEAT1 interaction represents a protective mechanism. We show that accumulation of human TDP-43 leads to upregulation of the constitutive NEAT1 isoform, NEAT1&#95;1, in cultured cells and in the brains of transgenic mice. Further, we demonstrate that overexpression of NEAT1&#95;1 ameliorates TDP-43 toxicity in Drosophila and yeast models of TDP-43 proteinopathy. Thus, NEAT1&#95;1 upregulation may be protective in TDP-43 proteinopathies affecting the brain. Approaches to boost NEAT1&#95;1 expression in the CNS may prove useful in the treatment of these conditions.

A convenient synthetic approach to novel functionalized bis(isoxazoles), the promising bivalent ligands of the AMPA receptor, was elaborated. It was based on the heterocyclization reactions of readily available electrophilic alkenes with the tetranitromethane-triethylamine complex. The structural diversity of the synthesized compounds was demonstrated. In the electrophysiological experiments using the patch clamp technique on Purkinje neurons, the compound 1,4-phenylenedi(methylene)bis(5-aminoisoxazole-3-carboxylate) was shown to be highly potent positive modulator of the AMPA receptor, potentiating kainate-induced currents up to 70% at 10 -11 M.

Graphitic materials including graphene, carbon nanotubes and fullerenes, are promising for use in nanotechnology and biomedicine. Non-covalent functionalization by peptides and other organic molecules allows changing the properties of graphitic surfaces in a controlled manner and represents a big potential for fundamental research and applications. Recently described oligopeptide-hydrocarbon derivative N,N'-(decane-1,10-diyl)bis(tetraglycineamide) (GM) is highly prospective for the development of graphitic interfaces in biosensor application as well as in structural biology for improving the quality of high-resolution atomic force microscopy (AFM) visualization of individual biomacromolecules. However, molecular organization of GM on graphitic surfaces is still unknown. In this work, the molecular model of GM at the water/highly oriented pyrolytic graphite (HOPG) interface has been developed basing on the high-resolution AFM and full-atom molecular modeling data. This model explains two periodicities observed in AFM images by GM self-assembly on a HOPG surface with formation of the stacks with the lateral shifts. The obtained results reveal the particular patterns and dynamics of GM molecules adsorbed on graphite and unravel the puzzle of peptide self-assembly on graphitic surfaces., (Copyright © 2021 Elsevier B.V. All rights reserved.)

First-principles density functional theory calculations on neutral and singly negatively and positively charged iron clusters Fe n and iron nitride clusters Fe n N and Fe n N 2 ( n = 1-10) in the range of 1 ≤ n ≤ 10 revealed that there is a strong competition between ferromagnetic and antiferromagnetic states especially in the Fe n N 2 0,±1 cluster series. This phenomenon was related to superexchange via a bridging N atom between two iron atoms in the Fe n N 2 0,±1 series. A thorough examination of the structure-energy-spin state relationships in these clusters is conducted, leading to new insights and confirmation of available experimental results on structural parameters and dissociation energetics. The bond energies of both nitrogen atoms in the Fe n N 2 series are approximately the same. They weakly depend on the charge of the host cluster and fluctuate around 5.5 eV when moving along the series. The energy of N 0,±1 desorption is relatively small; it varies by about 1.0 eV and depends on the charge of the cluster. The experimental finding that N n N 2 series are approximately the same. They weakly depend on the charge of the host cluster and fluctuate around 5.5 eV when moving along the series. The energy of N 2 = 4 was supported by the results of our computations. Our computed values of the Fe 2 -N bonding energies agree with the experimental data within the experimental uncertainty bars. It was found that the attachment of one or two N atoms does not seriously affect the polarizability, electron affinity, or ionization energy of the host iron clusters independent of the charge. n + clusters beginning with n = 4 was supported by the results of our computations. Our computed values of the Fe n + -N bonding energies agree with the experimental data within the experimental uncertainty bars. It was found that the attachment of one or two N atoms does not seriously affect the polarizability, electron affinity, or ionization energy of the host iron clusters independent of the charge.

A new approach for the annulation of a thiopyrane ring to an indole core under mild conditions was developed. Treating 2-methyl-3-acylindoles with lithium diisopropyl amide leads to the elimination of a proton from the 2-methyl group. The lithium indole-2,3-dienolates obtained were found to react with CS 2 to give the corresponding thiopyrano[4,3- b ]indole-3(5 H )-thiones. The mechanism represents a stepwise addition through ion-pair formation, according to PCM/B3LYP/6-311++G**, PBE1PBE/6-311++G**, and MP2//HF/6-311++G** quantum chemical calculations. AIM calculations revealed the essential role of the Li atom at all stages of the process.

The effects of the vibronic coupling in quantum cellular automata (QCA) based on the square planar mixed valence (MV) molecular cells comprising four paramagnetic centers (spin cores) and two excess mobile electrons are analyzed in the important particular case when the Coulomb energy gap between the ground antipodal diagonal-type two-electron configurations and the excited side-type configurations considerably exceeds both the one-electron transfer parameter (strong U-limit) and the vibronic stabilization energy. Under such conditions the developed model involves the second-order double exchange, the Heisenberg-Dirac-Van Vleck (HDVV) exchange and the vibronic coupling of the excess electrons with the molecular B 1g -vibration composed of four full-symmetric local vibrations. The latter interaction is shown to significant amplify the ability of the electric field produced by the driver-cell to polarize the excess electrons in the working cell, which can be termed "the effect of the vibronic enhancement of the cell-cell interaction". This effect leads to a redetermination of the conditions for switching between different spin-states, as well as to a significant change in the shapes of the cell-cell response functions. The obtained results demonstrate the importance of the vibronic coupling in all aspects (such as description of a free cell and cell-cell response) of the theory of molecular QCA based on MV clusters., (© 2021 Wiley-VCH GmbH.)