Mechanical Action Research Articles

Nonlethal Molecular Nanomachines Potentiate Antibiotic Activity Against Gram-Negative Bacteria by Increasing Cell Permeability and Attenuating Efflux.

Antibiotic resistance is a pressing public health threat. Despite rising resistance, antibiotic development, especially for Gram-negative bacteria, has stagnated. As the traditional antibiotic research and development pipeline struggles to address this growing concern, alternative solutions become imperative. Synthetic molecular nanomachines (MNMs) are molecular structures that rotate unidirectionally in a controlled manner in response to a stimulus, such as light, resulting in a mechanical action that can propel molecules to drill into cell membranes, causing rapid cell death. Due to their broad destructive capabilities, clinical translation of MNMs remains challenging. Hence, here, we explore the ability of nonlethal visible-light-activated MNMs to potentiate conventional antibiotics against Gram-negative bacteria. Nonlethal MNMs enhanced the antibacterial activity of various classes of conventional antibiotics against Gram-negative bacteria, including those typically effective only against Gram-positive strains, reducing the antibiotic concentration required for bactericidal action. Our study also revealed that MNMs bind to the negatively charged phospholipids of the bacterial inner membrane, leading to permeabilization of the cell envelope and impairment of efflux pump activity following light activation of MNMs. The combined effects of MNMs on membrane permeability and efflux pumps resulted in increased antibiotic accumulation inside the cell, reversing antibiotic resistance and attenuating its development. These results identify nonlethal MNMs as pleiotropic antibiotic enhancers or adjuvants. The combination of MNMs with traditional antibiotics is a promising strategy against multidrug-resistant Gram-negative infections. This approach can reduce the amount of antibiotics needed and slow down antibiotic resistance development, thereby preserving the effectiveness of our current antibiotics.

Phenols and GABAA receptors: from structure and molecular mechanisms action to neuropsychiatric sequelae.

γ-Aminobutyric acid type A receptors (GABAARs) are members of the pentameric ligand-gated ion channel (pLGIC) family, which are widespread throughout the invertebrate and vertebrate central nervous system. GABAARs are engaged in short-term changes of the neuronal concentrations of chloride (Cl-) and bicarbonate (HCO3 -) ions by their passive permeability through the ion channel pore. GABAARs are regulated by various structurally diverse phenolic substances ranging from simple phenols to complex polyphenols. The wide chemical and structural variability of phenols suggest similar and different binding sites on GABAARs, allowing them to manifest themselves as activators, inhibitors, or allosteric ligands of GABAAR function. Interest in phenols is associated with their great potential for GABAAR modulation, but also with their subsequent negative or positive role in neurological and psychiatric disorders. This review focuses on the GABAergic deficit hypotheses during neurological and psychiatric disorders induced by various phenols. We summarize the structure-activity relationship of general phenol groups concerning their differential roles in the manifestation of neuropsychiatric symptoms. We describe and analyze the role of GABAAR subunits in manifesting various neuropathologies and the molecular mechanisms underlying their modulation by phenols. Finally, we discuss how phenol drugs can modulate GABAAR activity via desensitization and resensitization. We also demonstrate a novel pharmacological approach to treat neuropsychiatric disorders via regulation of receptor phosphorylation/dephosphorylation.

Investigation of the Potential Targets and Mechanism Actions of Berberine in the Treatment of Pulpitis Based on Bioinformatics Analysis

Berberine, an active compound extracted from the Chinese herb, was reported to have an antibacterial effect and an anti-inflammatory effect and promote osteogenic differentiation of human dental pulp stem cells. However, the underlying therapeutic mechanism of berberine in pulpitis is still unknown. Here, bioinformatics analysis was performed to investigate the potential mechanism of berberine against pulpitis. First, we identified the collective targets of berberine and pulpitis from several databases using a Venny online tool. The pattern of interaction between berberine and the targeted protein was visualized by molecular docking. Moreover, we performed GSEA, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to obtain potential pathways. Cell experiments were performed to validate the bioinformatics analysis results. Prostaglandin-endoperoxide synthase 2 (PTGS2) was identified as the crucial antipulpitis target of berberine via the CytoHubba plugin. Docking analysis indicated that berberine could fit in the binding pocket of the PTGS2 protein. Additionally, berberine exerted its therapeutic effects against pulpitis via multiple pathways. Overall, berberine possessed therapeutic effects against pulpitis through the inactivation of toll-like receptor and NOD-like receptor signaling pathways. The present research proposes a novel approach to explore the therapeutic mechanism of natural products.

Research Progress on Superhydrophobic Surface Preparation Methods and Mechanical Durability

Abstract: Superhydrophobic surfaces have great application prospects due to their unique surface- wetting characteristics. However, superhydrophobic surfaces' micro-nano binary rough structure and low surface energy components are easily damaged or lost by wear and grease, which affects their durability and limits their practical application, so it is of great significance to study the durability of superhydrophobic surfaces. The review first introduces the preparation methods and application fields of superhydrophobic surfaces, then sorts out the test methods for the durability performance of superhydrophobic surfaces, methods to improve the durability of superhydrophobic surfaces are summarized， and finally points out some problems in the current research on the durability of superhydrophobic surfaces, aiming to have a comprehensive understanding of the research progress of durable superhydrophobic surfaces, provide some theoretical guidance for the development of durable superhydrophobic surfaces, and look forward to the development direction and trend of durable superhydrophobic surface research in the future. There have been substantial improvements achieved in the preparation techniques to increase the mechanical durability of superhydrophobic surfaces and widen their applications. This review examines pertinent patents and articles on the fabrication of superhydrophobic surfaces from both domestic and foreign sources. The paper introduces the fundamental preparation methods for superhydrophobic surfaces and examines three common techniques: the template method, the spraying method, and the etching method. Additionally, the study discusses these preparation methods and presents future development trends based on the latest research findings. Aiming at the mechanical durability of superhydrophobic surfaces, the test methods for the durability performance of superhydrophobic surfaces under mechanical action are reviewed. The paper also suggests four key methods for enhancing the durability of superhydrophobic surfaces. The refinement of superhydrophobic surface preparation techniques plays a crucial role in enhancing durability and broadening the applications of these surfaces. Additionally, it holds the potential to unlock new possibilities across various domains. The future holds promising prospects for the invention of additional patents and papers focused on superhydrophobic surfaces.

Cracking and thermal resistance in concrete: Coupled thermo-mechanics and phase-field modeling

Modeling damage and fracture in concrete accurately is crucial for a comprehensive analysis of structures under concurrent thermal and mechanical actions. This paper presents a novel coupled thermo-mechanical phase field model for concrete at high temperatures. Derived from principles of thermodynamics and unified phase field theory, the model integrates temperature-dependent thermal and mechanical properties, accounting for thermal expansion and transient creep. Mechanical damage, represented by the crack phase field, is augmented by a temperature-dependent thermal damage variable for heat-induced degradation. Addressing the impact of cracks on heat conduction and stress redistributions, the model introduces a novel approach to depict thermal resistance, seamlessly integrating mechanics, heat transfer, and crack propagation. Governing equations for damage evolution are derived, and the numerical implementation is detailed. Numerical illustrations showcase the model's ability to simulate diverse thermo-mechanical cracking patterns without explicit fracture path tracking or assumed criteria. Moreover, the model captures the influence of thermal actions on concrete cracking behavior and mechanical performance. This research is significant for predicting multi-field coupling damage in concrete and structures exposed to elevated temperatures.

Enamel and dentin of human teeth. Fatigue strength

The article provides a brief overview of the studies regarding changes in the structure and composition of teeth after eruption. The factors of degenerative changes in tooth structures and their relationship with non-carious lesions have been analyzed. The study makes emphasis on the tooth durability and the factors influencing tissue fatigue, explaining increased tissue wear due to local factors. Understanding mechanisms of metabolism of teeth hard tissues is the key to the stability of restorative treatments and occurrence of non-carious tooth lesions. The evolution of views on this problem is noteworthy. The literature review reveals the initial predominance of mechanical actions, abrasion, and mineralization. It is later complemented by a detailed analysis of the influence of destructive stresses and deformation due to mechanical factors. All the leading works of the 2000s are dedicated to analyzing the ultrastructural features of enamel that affect its mechanical characteristics and can explain both the characteristics of the shape and intensity of mechanical tooth wear during the functioning of the stomatognathic system, as well as the durability of the performed restorations. The literature review covers 74 sources over the past 15 years.

Review: Microemulsions for the Sustainable Development of EOR

Global oil and gas resources are declining continuously, and sustainable development has become a common challenge worldwide. In terms of environmental protection and economic benefits, the application of microemulsions for enhanced oil recovery often requires fewer chemical agents, showing distinct advantages. This paper analyzes the application prospects and trends of middle-phase microemulsions in tertiary oil recovery. The properties of middle-phase microemulsions are introduced, and an overview of the historical development, theoretical framework, influencing factors, and preparation methods of emulsions are provided. From the perspective of oil displacement systems, this paper reviews the selection and characterization methods of emulsions, as well as the interaction mechanisms between emulsions and reservoirs, proposing future research directions. The focus of the paper is on the evaluation and characterization of emulsions, the mechanisms of micro-oil displacement, and the application of advanced CT scanning technology, which gives a new understanding of wettability changes, capillary forces, and miscible solubilization processes, contributing to the reduction in displacement costs and the improvement of economic benefits. In conclusion, the middle-phase microemulsion flooding technique can significantly enhance oil recovery through the comprehensive action of various mechanisms and has been widely used in oil field development.

ВЛИЯНИЕ НА КАЧЕСТВО ПРОИЗВОДСТВА ШТУКАТУРНЫХ РАБОТ ПАРАМЕТРОВ РОБОТА-ШТУКАТУРА

The article considers the main aspects of studying the effective use of plastering machines and mixtures in construction through the use of automated and mechanized systems, units and robots. Theoretical aspect of the study of the process of plaster layer compaction with the help of a vibration platform of a robot plasterer with adjustable parameters. The main design and technological parameters of vibration compaction of the plaster layer and their influence on the efficiency of the process of compaction of vertical walls are revealed. The methods of experimental research are described, as well as experimental installations on which the laboratory experiment was carried out. The use of this technology allows to solve the problem of time costs and increase labor productivity indicators, as well as aspects of economic nature. When changing the physical and mechanical characteristics of the vibration platform its dependence of variation factors allows to form the most favorable conditions for the mechanical effect of vibrations on the efficiency of the process of plastering vertical walls. Plastering mixtures for obtaining a plaster layer are studied, the main physical and mechanical characteristics are analyzed, the requirements to be taken into account in the process of plastering are analyzed. The paper presents a comparison of physical and mechanical characteristics of the vibration platform, reveals the advantages and disadvantages of using different combinations of parameters. It is established that the use of a certain combination or change of one important parameter contributes to the increase of physical and mechanical characteristics in comparison with the traditional method of mechanical action.

Tribo-piezoelectric synergistic BaTiO3/PDMS micropyramidal structure for high-performance energy harvester and high-sensitivity tactile sensing

Triboelectric nanogenerators (TENGs) and piezoelectric nanogenerators (PENGs) represent some of the most promising strategies for converting mechanical deformation and friction into electrical energy. This energy can be used to power electronic devices, such as wearables, and detect mechanical stimuli. Here, we have demonstrated the synergistic integration of piezoelectric and triboelectric effects by incorporating barium titanate (BaTiO3) nanoparticles into a pyramidal polydimethylsiloxane (PDMS) elastomer. This integration aims to enhance the performance of both pressure sensor devices and electrical energy harvesters. The pressure sensitivity of our proposed tribo-piezoelectric device reaches as high as 3.71 V∙kPa−1 for pressure sensing within the range of 0.1–100 kPa, the output voltage increasing to ∼ 370 V at 100 kPa. Our theoretical simulation of electrical power density at this specific pressure reveals that the mechanical deformation of the PDMS elastomer, combined with the polarization of BaTiO3 nanoparticles, synergistically generate tribo-piezoelectric charge on the surface. Therefore, our synergistic combination of triboelectric and piezoelectric effects opens a promising avenue for effectively converting mechanical action into electrical signals. This enables highly efficient energy scavenging and the development of high-sensitivity pressure sensors.

Supramolecular immobilization of lipase inspired by octopus suckers for biodiesel production

It is still a challenge to design a supramolecular interaction system for immobilizing enzymes efficiently and stably. In this work, inspired by octopus suckers, we used cyclodextrin with a similar structure to the octopus sucker cavity as supramolecular interaction functional units of soft tentacles to immobilize lipase through physical adsorption. By modifying the surface of cyclodextrin with polar hydrophilic groups, the difference in hydrophilic and hydrophobic properties and stability within the molecule were effectively improved, thereby enhancing the cavity suction of cyclodextrin. The enzyme load of the soft tentacles reached 10 mg/g, and the lipase was adsorbed firmly under high strength mechanical action (the retention rate is 66.4%, other physical adsorption under the same conditions is 51.6%). The soft tentacle immobilized lipase showed good dispersibility in the organic phase and its water absorption characteristics could provide oil-water interface for lipase in organic phase reaction, promoting the forward transesterification reaction. Compared with free lipase, the soft tentacle immobilized lipase (L-CDST-Ms) showed the improved activity, which could reach 180% of that of free lipase. The L-CDST-Ms was applied to biodiesel production, and the conversion rate could reach 94%. The results showed that the immobilization method opened up a new way for the application of lipase in transesterification.

Quantum-Spacetime Symmetries: A Principle of Minimum Group Representation

We show that, as in the case of the principle of minimum action in classical and quantum mechanics, there exists an even more general principle in the very fundamental structure of quantum spacetime: this is the principle of minimal group representation, which allows us to consistently and simultaneously obtain a natural description of spacetime’s dynamics and the physical states admissible in it. The theoretical construction is based on the physical states that are average values of the generators of the metaplectic group Mp(n), the double covering of SL(2C) in a vector representation, with respect to the coherent states carrying the spin weight. Our main results here are: (i) There exists a connection between the dynamics given by the metaplectic-group symmetry generators and the physical states (the mappings of the generators through bilinear combinations of the basic states). (ii) The ground states are coherent states of the Perelomov–Klauder type defined by the action of the metaplectic group that divides the Hilbert space into even and odd states that are mutually orthogonal. They carry spin weight of 1/4 and 3/4, respectively, from which two other basic states can be formed. (iii) The physical states, mapped bilinearly with the basic 1/4- and 3/4-spin-weight states, plus their symmetric and antisymmetric combinations, have spin contents s=0,1/2,1,3/2 and 2. (iv) The generators realized with the bosonic variables of the harmonic oscillator introduce a natural supersymmetry and a superspace whose line element is the geometrical Lagrangian of our model. (v) From the line element as operator level, a coherent physical state of spin 2 can be obtained and naturally related to the metric tensor. (vi) The metric tensor is naturally discretized by taking the discrete series given by the basic states (coherent states) in the n number representation, reaching the classical (continuous) spacetime for n→∞. (vii) There emerges a relation between the eigenvalue α of our coherent-state metric solution and the black-hole area (entropy) as Abh/4lp2=α, relating the phase space of the metric found, gab, and the black hole area, Abh, through the Planck length lp2 and the eigenvalue α of the coherent states. As a consequence of the lowest level of the quantum-discrete-spacetime spectrum—e.g., the ground state associated to n=0 and its characteristic length—there exists a minimum entropy related to the black-hole history.

Mechanical and thermo-physical properties of heat and energy storage backfill based on MicroPCMs

Combining backfill mining with geothermal resource exploitation, geothermal extraction is achieved by using heat and energy storage functional backfill to achieve a win-win situation of mineral and geothermal co-mining. In this study, MicroPCMs were partially substituted for tailings to prepare phase change backfill material. The influence of different MicroPCMs contents (0, 5, 10, 15, 20 wt%) on the mechanical and thermophysical properties of backfill was investigated to determine the optimal MicroPCMs contents. The results showed that with the increase of MicroPCMs content, the strength exhibited a cliff-like drop at 5% followed by a gradual decline, as confirmed by the XTDIC full-field strain deformation measurement and analysis system. The thermal conductivity and thermal diffusivity decreased with the increase of MicroPCMs content, while the volumetric specific heat capacity and enthalpy showed an increasing trend. SEM scanning results indicated that MicroPCMs would fracture under mechanical action, and the fracture proportion increased with the increase in MicroPCMs content. The recommended MicroPCMs content was around 15 wt%, where the compressive strength, volumetric specific heat capacity, and enthalpy reached 5.2 MPa, 1.6 MJ/(m3·K) and 6.16 J/g, respectively. This study provides valuable insights into the influence of MicroPCMs on the strength and thermal properties of backfill materials.

CIRCA: Cloud-based intelligent robotic system for chemical analysis in streamlining and automating open-ended measurement tasks

The realm of chemical analysis has witnessed remarkable advancements through the automation of measurement techniques. This automation has played a pivotal role in reducing the labor-intensive and time-consuming aspects associated with chemical analysis, while simultaneously minimizing dependence on specialized knowledge. However, in practical analytical work, automated chemical measurement instrumentation faces persistent challenges due to uncertainties regarding the number and timing of sample measurement tasks reaching the laboratory for analysis. These challenges result in low instrument sharing rates and a deficiency in effective communication mechanisms between sample providers and administrators, impeding the further enhancement of automated chemical measurement efficiency. Here we proposed a Cloud-based Intelligent Robotic System for Chemical Analysis (CIRCA) and demonstrated its application by the analysis of soluble iron in water samples. CIRCA comprises a cloud platform and an analytical robot, which efficiently manages and executes measurement tasks using a Process Simulation Algorithm and a Task Coordination Algorithm. The Process Simulation Algorithm plans the mechanical actions of analytical robot modules, while simulating processing times for each task. Simultaneously, the Task Coordination Algorithm optimizes the timing of each measurement task. By adopting CIRCA, sample providers can remotely submit measurement tasks without negotiation, allowing for the seamless management of open-ended analytical tasks, measurement execution, and analytical result feedback, thereby enhancing the overall efficiency of the analytical workflow. CIRCA represents a pioneering cloud-based intelligent robotic system that revolutionizes chemical analysis by addressing persistent challenges in managing open-ended measurement tasks. Its innovative design and distinctive algorithms, coupled with cloud-based communication logic and architecture, as well as the robotic physical framework, empower seamless task coordination, remote synergism, automated execution, and result feedback, ultimately enhancing analytical efficiency.

MODELING OF VIBRATIONS OF A STACKED PIEZO ELEMENT MADE OF POROUS PIEZOCERAMICS

The work is devoted to a numerical study of the effectiveness of using porous piezoceramics in a stacked piezoelectric element, which can be used as a power drive element, a piezoelectric generator, or an ultrasonic emitter. The use of porous piezoceramics in stacked piezoelements has not received enough attention in the literature. The use of porous piezoceramics in stacked piezo elements has not received enough attention in the literature. The paper considers a stacked piezo element consisting of eight solid cylinders counter-polarized in the axial direction. The material of the cylinders is PZT-4 piezoceramic, the porosity of which varies from 0% to 80%. The problem of axial steady-state oscillations in the vicinity of the first resonance frequency and below it is solved. The lower end of the cylinder is fixed along the normal, excitation of oscillations is carried out by mechanical action under uniformly distributed pressure at the upper face or by the action of electric potential difference at the electrodes. The problems are solved in the framework of linear axisymmetric theory of electroelasticity. With mechanical action, the output characteristic of the device is the electrical potential of the free electrodes; with electrical action, it is the amplitude of the axial vibrations of the upper end or the reaction force if it is fixed. The finite element method implemented in the ACELAN package is used as the solution method. As a result of the numerical solution, the dependence of the percentage of porosity on the output characteristics of the piezo element is investigated: the frequencies of resonance and antiresonance, the electromechanical coupling coefficient, the output potential under mechanical loading, the amplitude of oscillations of the free upper end and the coupling reaction at its fixing when the oscillations are excited by the potential difference and the energy of the elastic element attached to this end. The analysis of the dependence of these characteristics allows us to conclude that it is reasonable to use such an element with porous ceramics as a piezoelectric generator and transmitter. It is noted that the choice of the percentage of porosity depends directly on the intensity of loads and the strength of porous piezoceramics.

Topical issues of countering modern autonomous unmanned aerial vehicles and FPV drones

The high level of development of unmanned aviation has predetermined the possibility of its use to solve a wide range of tasks. At the same time, it should be noted that achievements in this area are not always used for peaceful purposes. The results of the analysis of the practice of using unmanned aerial vehicles (UAVs) in modern military conflicts and information about terrorist acts with their use allow us to conclude that the most difficult targets resistant to various methods of influence are modern autonomous UAVs and FPV drones with explosive devices. Therefore, the search for effective ways to counteract them seems to be an urgent area of research. The aim of the work is to develop the means for effective counteraction to modern autonomous UAVs and FPV drones by electromagnetic, laser and mechanical ways. The methods of system analysis are used in the work. The article notes the increasing level of threats associated with the mass use of autonomous UAVs and FPV drones, presents the results of the "revision" and critical analysis of the main methods of countering modern UAVs, reflecting their characteristics, advantages and disadvantages. Based on the results obtained, a comparative analysis of methods of countering autonomous UAVs and FPV drones was carried out. It is concluded that the most effective of them are the methods of electromagnetic, laser and mechanical action. The required parameters for the effective application of these types of impacts on modern autonomous UAVs and FPV drones are presented. The results of the research can be used as initial data for the creation of new and improvement of existing means of countering UAVs as part of physical protection systems (SFZ). The scientific novelty of the work consists in the development of a scientific and methodological apparatus for substantiating the SFZ of objects in terms of taking into account the functioning features and vulnerabilities of modern autonomous UAVs and FPV drones, as well as determining ways to improve systems to counter them based on the use of electromagnetic, laser and mechanical means.

Virucidal activity of chlorine dioxide in combination with acetic acid or citric acid and a surfactant, in presence of interfering substances, against polio-, adeno- and murine norovirus in suspension-, carrier- and four-field tests.

The aim of the study was to investigate whether the virucidal effectiveness of chlorine dioxid against adenovirus and murine norovirus can be improved by combining it with carboxylic acids and surfactants. The virucidal efficacy against polio-, adeno- and murine norovirus has been tested in presence of interfering substances in the quantitative suspension test according to EN 14476, the carrier test without mechanical action according to EN 16777, and in the four-field test according to EN 16615.Three chlorine-dioxide-based surface disinfectants were tested: a two-component cleaning disinfectant concentrate for large surfaces, a ready-to-use (RTU) foam, and an RTU gel. Cleaning and disinfecting preparations based on chlorine dioxide, applied at various concentrations, in combination with acetic acid or citric acid and surfactants, are virucidally active against polio-, adeno-, and norovirus after an exposure time of 5 minutes in presence of interfering substances.

Microplastics in Synthetic Textile Industries: Origin, Occurrence, Routes and Their Fates on Environment and Human

This article highlights the possible origin, occurrence, and environmental pathways of microplastics (MPs) in the synthetic textile sector. It focused on comprehensive knowledge of the MP in industry, emphasizing the importance of an integrated approach to addressing its extensive consequences. The emission of MPs during the production of textiles including spinning, weaving, dyeing, printing, or finishing. It found that many small fragments, microfibres, sequins, buttons, foams, and other packaging materials made up of plastics such as polyester, polyamide, polyethylene terephthalate, polyacrylonitrile, polyethylene, and many more are weathered from large pieces of clothes and yarns by mechanical action or other degradation methods. In addition, several sources and processes of production that are accountable to MPs have been discussed in the synthetic textile industry. Finally, the effects of MPFs (microplastic fibres) on the environment and, more specifically, on humans were put forth.

Upper Miocene aragonite sediments of the Eastern Paratethys (Zheleznyi Rog section): Whiting events or not?

The upper Sarmatian and lower Maeotian unlithified aragonite sediments of the Zheleznyi Rog section (Taman Peninsula, Eastern Paratethys, Russia) were investigated by field observations and laboratory methods, including scanning electron microscopy, X?ray diffraction and isotope analyses. Aragonite sediments occur at separate intervals of the studied section, forming thin (millimeter?sized) interlayers with clays. These carbonate sediments consist almost entirely of crystals (individuals and twins) and aggregates of aragonite, ranging in size from 5 to 23 ?m. It is assumed that the isotopic composition (?13C = 5.7 and 5.3?, ?18O = ?2.4 and ?2.8? for upper Sarmatian and lower Maeotian aragonites, respectively) reflects the sedimentation conditions, chara cterized by reduced basin salinity, increased surface water bioproductivity, and periods of aridization. Abiotic precipitation of these aragonites most likely occurred due to the action of triggering mechanisms, which could include planktonic algae blooms (e.g. diatoms). The obtained results do not contradict the hypothesis that the studied aragonites may be considered as sediments of whiting phenomenon.

Ecological innovations in the development of sustainable tourism

In a situation of a significant increase in risks and restrictions imposed by the action of homeostatic mechanisms of the biosphere, without taking into account the environmental imperatives of development, it will not be possible to prevent irreversible anthropogenic changes in natural complexes. For the tourism sector of the economy, for which the high quality of the natural environment is vital, the problem of stimulating innovations in the field of rationalization of nature management and resource conservation is particularly relevant. The development of sustainable tourism involves the integration of environmental, economic and social principles of managing biological and physical ecosystems in such a way as to protect environmental sustainability, biological diversity and environmental productivity. It is environmental innovations in tourism that play a significant role in increasing the efficiency of using natural ecosystems, preserving the wealth of natural heritage and biological diversity. The aim of the work was to study the potential, conditions, key factors for the practical implementation of environmental innovations in the tourism industry, as well as the development of mechanisms for the implementation of state policy aimed at transforming tourism activities on ESG principles. The scientific novelty of the work consists in identifying current priorities and measures for integrating environmental and innovation policies in relation to the tasks of ensuring sustainable tourism development by using the benefits of their joint implementation.

Up-regulation of myelin-associated glycoprotein is associated with the ameliorating effect of omega-3 polyunsaturated fatty acids on Alzheimer's disease progression in APP-PS1 transgenic mice.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive behavioral and cognitive impairments. Despite growing evidence of the neuroprotective action of omega-3 polyunsaturated fatty acids (PUFAs), the effects and mechanism of omega-3 PUFAs on AD control are yet to be clarified. By crossing male heterozygous fat-1 mice with female APP/PS1 mice, we assessed whether elevated tissue omega-3 PUFA levels could alleviate AD progression and their underlying mechanism among the offspring WT, APP/PS1 and APP/PS1 × fat-1 groups at various stages. We found that the fat-1 transgene significantly increased brain omega-3 PUFA and docosahexaenoic acid (DHA) levels, and cognitive deficits together with brain Aβ-40 and Aβ-42 levels in 6-month-old APP/PS1 × fat-1 mice were significantly lower than those in APP/PS1 mice. Subsequently, the tandem mass tag (TMT) method revealed the elevated expression of cortex and hippocampus myelin-associated glycoprotein (MAG) in APP/PS1 × fat-1 mice at 2-6 months. Furthermore, GO and KEGG pathway enrichment analysis suggested that the MAG-related myelin sheath pathway and its interaction with AD were regulated by omega-3 PUFAs. Moreover, subsequent western blot assays showed that both increased endogenous omega-3 levels and in vitro supplemented DHA up-regulated MAG expression, and the AD-protective effects of DHA on LPS-induced BV2 cells were significantly weakened when MAG was inhibited by si-RNA transfection. In summary, our study suggested that omega-3 PUFAs might protect against AD by up-regulating MAG expression.